Hur blir man en bra problemlösare?

Problemlösning kommer vi i kontakt med i många olika situationer och sammanhang, både i skolan, arbetslivet och i privatlivet. För att kunna lösa problem behöver man givetvis en hel del kunskaper kopplade till det specifika ämnesområdet. Men det finns även en del generella saker, strategier och metoder man kan använda sig av för att bli en bättre problemlösare.

Problemlösning kan delas in i följande områden:
Problemlösningens faser, tänkbara strategier vid problemlösning och de kompetenser som är nödvändiga hos en problemlösare.

Elevernas arbete med ett problem kan delas upp i fyra successiva faser:

  • att förstå problemet
  • att göra upp en plan
  • att genomföra planen
  • att se tillbaka och kontrollera resultatet

En av de viktigaste faserna för lärande är den sista, att efter man tror sig kommit fram till en lösning se tillbaka, kontrollera resultatet och reflektera.

Några frågor man kan ställa sig är: 

  • Stämmer lösningen verkligen med de förutsättningar som ges i problemet?
  • Finns det något annat, kanske enklare sätt att lösa problemet på?
  • Kan jag kontrollera mitt resultat genom att lösa problemet på ett annat sätt?
  • Har jag upptäckt några nya spännande samband som jag kan ha nytta av i andra sammanhang?

Strategier för en bra problemlösningsplan:

  • välja en eller flera laborationer att arbeta med
  • rita bilder
  • söka mönster
  • arbeta baklänges
  • göra en lista
  • skriva upp en ekvation
  • dramatisera situationen
  • göra en tabell eller ett diagram
  • gissa och pröva
  • lösa ett enklare problem först
  • använda laborativa material
  • Bygga och använda modeller
  • Bygga och använda prototyper
  • Använda simuleringsverktyg
  • Kolla hur du själv eller andra löst liknande problem tidigare
TIS-projekt Oceanhamnen

TIS-projekt Oceanhamnen

Drönarfoto över Oceanhamnen och Pixlapiren 22 januari 2020

Det händer mycket i Oceanhamnen i Helsingborg nu.
Oceanhamnen är första etappen av stadsutvecklings-projektet H+ i Helsingborg som fram till år 2035 ska omvandla en miljon kvadratmeter gammalt hamn- och industriområde till de fyra stadsdelarna Oceanhamnen, Universitetsområdet, Husarområdet och Gåsebäck och ge plats för 10 000 nya invånare. Syftet är att skapa framtidens smarta hållbara stad och då behöver vi självklart involvera eleverna på Innovationsgymnasiet i Helsingborg!

Alla viktiga projekt behöver en flygande start!
Först ut på bollen är teknikeleverna i årskurs 2 (TE18DP) som läser Design, Konstruktion, CAD och produktutveckling som, förutom att skapa 3D-ritningar med inredningsförslag till blivande bostadsrätter, kontor och hotell, även kommer bygga fysiska 3D-modeller av de nya bostäderna. Teknikeleverna i årskurs 1 (TE19) är också med i projektet och kommer jobba med fasadritningar och bygga skalenliga modeller av fastigheternas fasader inom kursen Teknik 1.
TE18DP ska även designa och konstruera förslag på smarta, kompakta och mobila modulära studentbostäder av återbruksmaterial.
Som en naturlig del i projektet väver vi in innovativa tekniska lösningar för smarta hem, intelligenta byggnader med lokal energiåtervinning och system för användarcentrerad feedback i syfte att minska varje individs energi- och vattenförbrukning och avfallsmängd. För de projekt och produktidéer som rör IoT (Internet Of Things) och digitala lösningar kommer våra elever (TE18IM) som läser Dator- och Nätverksteknik, Programmering, Webbutveckling och certifieringskursen Cisco IoT Fundamentals Connecting Things involveras.
Genomgående för uppdragen är tillämpning av principer för hållbar design och användandet av moderna professionella digitala design- och konstruktionsverktyg som Blender, Sketchup, Fusion 360, Meshroom, Autodesk Revit, Unity, Unity Reflect samt 3D-skrivare och återbruksmaterial för att skapa skalenliga fysiska modeller.
Under våren kommer natureleverna (NA19), som en del av projektet ”TIS-Tema Vatten”, titta närmare på den nya innovativa vattenreningsanläggningen Reco Lab (se mer info nedan) som är en modell för framtidens avloppssystem som håller på att byggas i Oceanhamnen.

Oceanhamnsområdet är just nu en inhägnad byggarbetsplats där förvandlingen till en levande stadsdel med de första 450 bostäder pågår för fullt så att de första invånarna kan flytta in redan nästa år. Här byggs också restauranger, handelsyta och Oceanhamnen Waterfront Business District, ett nytt affärsdistrikt med 32 000 kvadratmeter nya kontor. Området får endast besökas av behörig personal med ID06 passerkort, så vi har inte möjlighet att gå dit och göra fältstudier på nära håll med eleverna. Så för att få en inblick i hur arbetsprocesserna och bygget fortskrider får vi ta till andra kreativa metoder. I första hand söker vi samarbeten med de aktörer som är inblandade i olika delar av Oceanhamnen-projektet.

För att få lite perspektiv på projektet, fågelperspektiv alltså, så lyfte jag blicken och flög runt ett par varv och kollade in hur området ser ut idag, den 22 januari 2020.
Här nedan är ett litet filmklipp med en helikoptervy över området som vi kommer ha under luppen de närmaste månaderna.

För att få en känsla för hur det är tänkt att se ut när Oceanhamnen är färdigbyggd så är en 3D-visualisering med realistisk rendering ett bra och kraftfullt verktyg. Här nedan får du en förhandstitt i 3D på den nya stadsdelen som håller på att växa fram med ett spektakulärt läge vid havet, ett stenkast från Helsingborgs centralstation. För att skapa en sådan film kan man t ex använda programvaran Blender 2.81 som vi börjat använda i kurserna Design, Konstruktion och Cad.

Välkommen till Oceanhamnen – 3D visualisering (3:05)

Digitalisering möjliggör nya innovativa arbetssätt
Om man vill gå ett steg längre och erbjuda en interaktiv upplevelse så att besökaren själv kan navigera runt i 3D-miljön så kan man istället lägga in de 3D-objekt man skapat i t ex Fusion 360 eller Sketchup, i spelutvecklingsmiljön Unity, som vi använt i undervisningen i Programmering. I Unity kan man även skapa en interaktiv VR- eller AR-upplevelse. Med Unity Reflect kan man sedan koppla samman konstruktionsritningarna och projektplaneringsverktygen och följa hela byggprocessens alla olika steg i VR från en annan plats, eller med hjälp av AR-teknik se hur byggnaden steg för steg kommer att byggas upp precis där du står, trots att det ännu inte är klart. Det är som att i realtid kunna se in i framtiden, in genom väggar eller tillbaka till hur någonting såg ut innan.

Unity Reflect gör konstruktionsdokument och ritningar digitalt tillgängliga på byggarbetsplatsen i realtid via AR.

Här kan du se var byggherrarna bygger

Det är totalt sex byggherrar som ska bygga bostäder i den nya stadsdelen. Vi vill gärna samarbeta med dem på olika sätt inom ramen för de kurser eleverna läser, men även för SYV (Studie- och Yrkes-Vägledning). Det kan t ex handla om studiebesök, intervjuer, designuppdrag eller praktikplatser.
Kartan härunder visar var de ska bygga, och länkarna går till mer information om dem och deras projekt.

 Kartan visar var det ska byggas bostäder i oceanhamnen
Översiktskarta över Oceanhamnen med markeringar för placeringen av de olika byggherrarnas bostadsfastigheter.

Vid havet, mitt i centrum

Oceanpiren är en del av Oceanhamnen, ett nytt spännande bostadsområde mitt i Helsingborg. På bästa läge, längst ut på piren, bygger vi 69 bostadsrätter om 1-4 RoK – Brf Oceanpiren. Här bor du på första parkett vid havet, i hjärtat av stadsdelen, i ljusa, välplanerade bostadsrätter som är byggda för en hållbar livsstil. Samtidigt om vi uppför Brf Oceanpiren bygger vi fyra radhus i townhouse-stil. Vi kallar dem Oceanvillorna. De har både hållbarhetstänket och den magnifika havsutsikten gemensamt med Brf Oceanpiren.

Brf Oceanpiren

För mer information om Brf Oceanpiren se oceanpiren.se, den interaktiva presentationssidan för de olika bostadsobjekten eller de två faktabladen (pdf) för hus 1 och hus 2.

Interaktiv presentationssida för de olika bostadsobjekten.

Design-, konstruktions- och CAD-uppgifter till TE18DP
Här är en lista på exempel på arbeten och uppdrag som eleverna ska jobba med. Mer utförliga och detaljerande instruktioner ges under lektionerna, men de olika uppgifterna publiceras också på sidorna Designuppgifter för TE18DP och Konstruktions- och CAD-uppgifter för TE18DP.

  • Skapa en CAD-ritning på en av lägenheterna i Brf Oceanpiren. Utgå från planritningen.
  • Skapa ett komplett inredningsförslag till lägenheten.
  • Skapa konstruktionsritningar av väggsektioner, tak och golv i minst två olika material.
  • Skapa en materiallista och kostnadskalkyl för de ingående konstruktionselementen.
  • Gör hållfasthetsberäkningar och riskanalyser
  • Jämför materialalternativen med hänsyn till kostnad, hållfasthet, hållbarhet, miljöpåverkan, klimatavtryck och möjlighet till återvinning (livscykelanalys).

Oceanvillorna

De townhouse-inspirerade Oceanvillorna är Oceanpirens mest fulländade boende med spektakulära solnedgångar och en magnifik havsutsikt

https://public.wec360.se/midroc/oceanhamnen/a-1003/index.html

World Trade Center Helsingborg

World Trade Center Helsingborg i Oceanhamnen ska bli mötesplatsen för entreprenörer, scale-ups, etablerade företag och affärs- och helgresenärer.

MP_kontor_99493_WTC Oceanhamnen_Bröderna Pihls gränd_västerbild ([3149][@[resize:5200,2930][crop:34,0,5021,2919][autoorient:][background:%23ffffff][quality:80][strip:][extension:jpg][id:7]]).jpg
World Trade Center med Scandic Hotel Helsingborg på Bröderna Pihls gränd

WTC Helsingborg blir en kontors- och hotellfastighet som kommer bli ett landmärke i Helsingborg. Med sina fjorton våningar precis vid hamninloppet ger den dig närkontakt med sundet, båtarna och kontinenten. Här kommer finnas gemensam service som reception och konferensavdelning. Gym, relax, dusch- och omklädningsrum. Restaurangen med uteservering vid vattnet och takterasser är ytterligare fördelar som berikar både arbets- och privatliv. I källaren planeras för cykelgarage med möjligheter till reparationer och en laddstation för elcyklar.    

Fastighet är ritad av Juul Frost Arkitekter, men byggherren Midroc välkomnar kunderna tidigt in i processen för att kunna påverka lokalens utformning så att den passar verksamheten bäst. Att vara med och arbeta med förslag på lokalernas utformning kan vara ett bra elevprojekt!
Juul Frost Arkitekter är förövrigt experter på design av campusområden och studentbostäder, och hur man kan integrera dem i städer.

Läs mer om World Trade Center Helsingborg på följande länkar:
https://www.midroc.se/fastighetsutveckling/ny-lokal/nybyggnadsprojekt-lokaler/helsingborg-world-trade-center/

https://www.wtcmalmolundhelsingborg.se/fastigheter-och-lokaler/vara-fastigheter/helsingborg/broderna-phils-grand/

Se en typskiss på en kontorslokal i WTC:
https://www.wtcmalmolundhelsingborg.se/globalassets/lime/documents/483701-pdf-document.pdf

Oceanhamnen får ett innovativt nytt avloppssystem – Reco Lab med Tre Rör Ut

Innovativt avloppssystem i Oceanhamnen kräver nytänk (2:13)

Oceanhamnen kommer få en helt ny typ av klimatsmart avloppssystem med värmeåtervinning och lokalt producerad biogas. Varje fastighet ansluts till tre separata rör, ett för matavfall, ett för gråvatten och ett för svartvatten. Detta innovativa avloppssystem kräver att ingenjörerna tänker utanför boxen. I filmklippet ovan berättar VA-ingenjören Peter Winblad på Nordvästra Skånes vatten och avlopp, NSVA, om utmaningarna.

Reco Lab – en testbädd och showroom för framtidens källsorterande avloppssystem

Reco Lab kommer att bidra till att utveckla det världsunika systemet Tre Rör Ut för insamling och hantering av mat- och toalettavfall i fastigheterna på Oceanpiren i stadsdelen Oceanhamnen i centrala Helsingborg.

På uppdrag av NSVA har entreprenörföretaget NCC upphandlat det nederländska företaget Landustrie och det svenska företaget EkoBalans Fenix AB för att installera processteg i det unika Reco labs utvecklingsanläggning. Reco lab, som är en del av Öresundsverket i Helsingborg, ska behandla det källsorterade avloppet från Helsingborgs nya stadsdel, Oceanhamnen. Avloppshantering har en naturlig roll att spela i den cirkulära ekonomin då mycket av våra essentiella resurser, som vatten, näringsämnen och organiskt material passerar igenom stadens avlopp.

Det källsorterande avloppet innebär en reningsprocess med kraftigt ökad resursåtervinning. Miljövinsterna är flera:

  • ökad biogasproduktion
  • ökad näringsåtervinning
  • effektiv värmeåtervinning
  • mer energieffektiv läkemedelsrening
  • minskad klimatpåverkan
  • möjligheten för vattenåtervinning 

    Reco Lab planeras att vara färdigbyggt och driftsatt våren 2021 och inkluderar även ett showroom för utbildning samt en testbädd för teknikutveckling.
    Studiebesök hos NSVA för natureleverna (NA19) är planerat till maj 2020.
    Eleverna i NA18 borde också studera Reco Lab som en del av biologi- och kemikurserna, i synnerhet de som valt inriktningen mot natur och samhälle.

Bilder på bygget av Oceanhamnen

Bilder från fältstudie vid Oceanhamnen och Pixlapiren 2020-01-22 med drönaren DJI Spark:

Drönarvy | Helsingborg Oceanhamnen 2019-02-24 (Helsingborg då & nu)
Drönare för undervisning

Drönare för undervisning

På denna sida hittar du en lista på de drönare IKT-Labbet har för användning i undervisning. För mer information gällande respektive modell finns länkar till andra sidor eller så är det bara att Googla eller söka efter informationsfilmer på Youtube.

DJI Spark

DJI Spark

DJI Spark drönare är liten nog för att startas från din handflata och levererar en exceptionell bild och videoinspelning. Drönaren är utrustad med en kamera med 1/2.3” sensor som spelar in Full HD 1080p videos vid 30 fps eller 12 MP stillbilder.

Produktegenskaper

  • Spela in video i Full HD 1080p
  • Upp till 2km räckvidd
  • Hastighet upp till 50km/h
  • 16 minuters flygtid på en laddning
  • 2-axlad gimbal
  • 12 Megapixels stillbilder

Ryze Tello Powered By Dji Drönare

Ryze Tello Powered by DJI

Lättflugen drönare med kamera

  • Styrs direkt med mobilen
  • Kan programmeras
  • Gör tricks i luften

Självstabiliserande och lättflugen nybörjardrönare. Styrs på mobilskärmen med Ryze-appen där också bilden från drönaren visas. Kan användas med trådlös handkontroll, starta och landa i handen och har sensorer för kollisionsfri flygning.

Bygga en egen autonom bil – The Batmobile

Bygga en egen autonom bil – The Batmobile

Smiling big in Batmobile

Test driving the Batmobile

The thrill of taking a corner, extremely low to the ground, with your gut telling you these g-forces are not normal… that’s why we spend countless hours building these silly Power Wheels vehicles. The giggles and grins are unavoidable! These cars are so much fun to drive — and even more fun to race!

Toni the race car driver

In 2016, SparkFun had its eighth annual Autonomous Vehicle Competition. This year saw the introduction of a new rule: you needed to carry a human (or a 20lb dead weight in the form of a watermelon if you were too chicken). To do this, my wife, Alicia, and I modified a Batmobile Power Wheels and combined it with a Razor chassis. The result was an extremely zippy electric go-kart that left a perma-grin on everyone who drove it.

Our goal was to create a vehicle that could quickly and easily switch between human driver and driverless modes so that we could compete in both PRS and A+PRS categories. In the end, Alicia placed a very respectable third place in the driver category, and I did not finish (DNF) in the autonomous category, running into numerous hay bales.

This tutorial attempts to document a six-month build process for an Autonomous + Power Racing Series (A+PRS) vehicle. Every autonomous vehicle is unique, and the requirements of each will vary from build to build.

Batmobile with top off

Materials

You can see our overall budget, including a list of components and vendors here.A+PRS BATMOBILE MATERIAL SPREADSHEET
You can get all the code from our repo here.A+PRS BATMOBILE GITHUB REPOSITORY

Chassis

The AVC rules stipulate that you cannot spend more than $500 on your total budget and that you have to stay within certain size restrictions. We started trolling craigslist to see what was out there and immediately found a plethora of free or cheap “broken” Power Wheels. When a Batmobile for $25 popped up, we quickly snagged it.

Dusty Batmobile

Dusty with dog hair and dead spiders — it’s perfect!

The primary failure of all used Power Wheels is a dead battery. The Batmobile was no different; as soon as we put in a new 12V SLA (Sealed Lead Acid), it happily, albeit slowly, drove around. There is nothing magical about “Power Wheels” branded batteries; get the right voltage (usually 12V, sometimes 6V), and you can use almost any battery you’d like.

The original batmobile chassis blow molded plastic at its finest. The wheels are hollow, the motor is designed to move a child slowly (and reasonably safely), and the steering is littered with bits of metal but mostly loose and wobbly. While the stock chassis was capable of moving adults weighing in at around 200lbs, we knew it wouldn’t handle racing, so we decided to find a metal chassis to sit underneath.

Razor Drifter in box

Note the size of the motor and battery. Those are about to get much larger.

Razor is known for their kick scooters, but they’re in the electric go-kart market as well. We found a Razor Drifter Open Box for $165. The Drifter had the steering, brakes, wheels and chassis sorted out for us! Additionally, the Drifter came with a stock 24V battery, 250W motor and 250W motor controller.

Many PRS and AVC competitors are talented enough to weld their own chassis together. DIY welding is a great way to save money, but it may take weeks of fabrication. Because we planned to enter the autonomous field, we decided to find a ready-made chassis and spend our time building and debugging the autonomous bits.

Putting on a Hat

Once we had the Power Wheels and the Razor chassis, we had to combine the two.

We slid the razor chassis underneath the plastic batmobile shell. The razor chassis has strength where we needed it most: steering, chassis, brakes, drive train, everything. The plastic batmobile is just there as a shell. The four solid plastic+rubber razor wheels make contact with the ground. The four hollow batmobile wheels hover above the ground and are there only for cosmetic looks (for the lulz).

A Power Wheels meets a Drifter

A Power Wheels meets a Drifter

At some point you have to get out the reciprocating saw and severely modify your beautiful Power Wheels. We laid the Batmobile over the Razor and proceeded to chop off all the bits that got in the way.

Bare metal chassis

Bare metal chassis before shell is laid on top

Combined Batmobile

Seats? Where we’re going, we don’t need seats!

Pleasingly, the Batmobile sits on top of the chassis under its own structural support. We didn’t need to add all-thread or other standoffs. Even though they don’t do anything, we reattached the original wheels just so it looked extra wacky.

Motor and Motor Control

New larger motor on chassis

Moar!

In 2016, A+PRS allowed 48V systems, so the first thing we did was remove the 24V motor and install a 1,000W 48V/21A motor. The PRS rules limit any system to 1,400W, so we could have gone larger had budget constraints not been kicking in fast. New mounting holes were drilled into the chassis, and a different gear had to be mounted to the end of the motor. But it all went well. The stock chassis even included a chain tensioner that proved invaluable!

The MY1020 48V motor we used is common on the PRS circuit and performed great. However, our original 1,000W motor controller (you should already be able to tell what’s coming) did not do so well. Our first tests of the 48V system in an open parking lot worked great until the motor controller overheated and failed. And when MOSFET-based motor controllers fail, they fail unsafe, meaning our vehicle decided to go to 100 percent throttle and stay there. This is why we have safety switches! Alicia and I were able to kill the vehicle before anyone got hurt.

This failure should have been prevented: a motor controller should be rated for at least 2 times what you calculate your maximum load will be. In our case, if we wanted to control a 1kW motor, we should have been using a motor controller rated to a constant 2kW load. Luckily, the A+PRS rules don’t require you to record how much money you spent (and burned up); you have to report only what is on the vehicle as it rolls on race day.

Larger 5kW motor controller

The new, larger 5kW motor controller

We quickly located a larger, 5kW motor controller (this one even had reverse!) and got it on order. This larger motor controller has been working swimmingly ever since. Find a motor controller with reverse. You’ll be tempted to drive your souped-up Power Wheels in weird places (like the SparkFun inventory aisles), and a reverse gear allows for hilarious 5-point turns.

Brakes

Small Drum Brake

Go-kart drum brakes on eBay

The Razor chassis had the classic drum brake, perhaps the weakest link of the Razor. While the stock brake was probably the appropriate size for a 75lb child with stock 24V batteries, our brakes got really squishy once we added an additional 125lbs of meat bag, batteries and plastic bits. We rarely, if ever, used the brakes during races, but the PRS rules stipulate that your qualifying lap must end with the driver crossing the finish line and braking to a stop:

At the end of the hot lap, your car will have to come to a complete stop within 18ft of when its transponder crossed the start/finish line. Deliberately skidding, swerving or spinning out is not an acceptable method of braking for the brake test.

Alicia had to do an impressive combination of hard braking, swerving, skidding and sliding with such a dramatic flair that she wooed the judges into not noticing how dodgy our brakes were. We’ll have disc brakes installed before we roll in the 2017 race.

Batteries

Batteries installed on chassis

Battery holder welded onto the front of the chassis

As part of the motor upgrade, we needed to increase the battery voltage to 48V. To save money, we reused the super common batteries that came with the 24V Razor chassis. Razor was smart; they looked at the SLA (Sealed Lead Acid) battery industry and picked the most common size. This just happened to be the same battery that goes into nearly every UPS on the planet. We purchased two additional UPS-size batteries (way cheaper than buying Razor-brand batteries) and wired them in series.

4 batteries combined into one unit

Four batteries combined in series

Taping the cells together and adding a bead of hot glue between the cells made the pack nicely rigid. A low-cost, polarized, high-current connector finished off the pack. We had an old strap lying around that made all the difference in the world; it’s a lot more comfortable carrying the pack one-handed by its handle than with two hands underneath.

Polarized high current connector

Avoid fires and other bad things. Use polarized connectors for your batteries.

Wire

Soldering large gauge wire

Soldering large-gauge wire

We originally spec’d out some really nice, super flexible silicone-sheathed 8AWG wire for power distribution. I don’t think we would do this again; 10AWG would have been fine, and probably even 12AWG. As 8-gauge is far less common, the wire and connectors are more expensive, and the larger gauge wire takes a lot more soldering heat — it’s just a pain to work with. If you need the current capacity, go for it, but for our extremely zippy, 48V 20A vehicle, 8-gauge wire was overkill.

If you decide to use super flexible, large gauge wire, spend some time on the internet reading about how to solder this type of wire.

The best technique I found:

  • Make sure you’ve got heat shrink in place
  • Turn your soldering iron up to 425C (way hotter than the 325C usually needed)
  • Push the ends of wire together
  • Wrap tightly with 30AWG wire wrap wire
  • Liberally apply flux
  • Heat and insert lots of solder until the joint turns silver

Here’s a good video demonstrating this technique:

Kill Switch

We documented how to build a wireless kill switch while making margaritas. It was a ton of fun, so we’ll skip the bits of the wireless kill switch system here.

Smiling girl in power wheels

Zroooommmm!

In addition to the wireless disconnect, we had a large, red mushroom kill switch that disconnected the battery with a pleasing and authoritative ”thunk.” Pulling up on the mushroom button reconnects the battery to the system.

Mushroom kill switch on vehicle

Batman logo or Bitman logo?

As a pleasant bonus feature, the mushroom kill switch got rid of the nasty sparks. When connecting the battery to the motor controller, there was such an inrush of current into the capacitors and electronics that the connector would spark. Once we got the kill switch installed, we could connect/disconnect batteries without these sparks.

Large gauge power connector

Connector between kill switch and power bus

The top of the Batmobile was easily removed, but because it had the kill switch installed we needed a way to disconnect it easily from the power bus. We found a great high-power connector in a dead server UPS. These are often called ”winch connectors”, because they are higher current. With this connector, we are able to quickly disconnect the kill switch and remove the top when we need to get at the inside of the vehicle.

Control Electronics

Main controller board

Power converters, motor kill relays, steering relays, locomotion controller and wireless communication

The control electronics are complex. We had a total of seven microcontrollers on this beast, plus three used in the distance sensors for a total of 216 bits of processing power. The system operated on an I2C bus with the brain sending commands to the locomotion controller and LCD and receiving data from the sensors.

Wiring inside the Batmobile

The wiring underneath the Batmobile cover

For a previous 2010 AVC entry, I did everything on a single microcontroller. This made coding and debugging a challenge. On our 2016 entry, we focused each sub-system to do one thing very well.

The subsystems are broken down as follows:

  • Brain Controller: A SAMD21 Mini was used to communicate with and process all the data from the distance sensors, GPS and compass, and to send out commands to control throttle and steering. It monitored a start switch and relayed debug information to an LCD.
  • Locomotion Controller: An Arduino Pro Mini read the throttle, steering position, brake switch and autonomous rocket switch. It controlled motor speed and the linear actuator for steering.
  • Wireless Kill Switch: An Arduino Pro Mini lived in the wireless kill switch, a requirement for the autonomous part of our Batmobile. To learn more about the wireless controller, check out our tutorial on how to build a wireless kill switch.
  • A dedicated Arduino Pro Mini controlled the relays for the wireless kill switch system.
  • Debug LCD: We counted our LCD screen as a microcontroller since it has an Arduino in it.
  • Sensor Combinator: A SAMD21 Mini polled the serial GPS and I2C compass.
  • Laser Controller: A SAMD21 Mini controlled the three serial-based laser distance sensors, combined the relevant information and responded to requests from the Brain.
  • Three STM32s were the brains within the laser distance sensors.

Interested in learning more about distance sensing?

Learn all about the different technologies distance sensors use and which products would work best for you next project.TAKE ME THERE!


Control Electronics – Brain

Controller and reverse knob

The Brain is a SAMD21 Mini. It sends commands over the I2C bus to the locomotion controller and debug LCD.

4-pin JST connector at the top of the image: We used a 4-wire bus (5V, GND, SDA, SCL) for communication and had various taps throughout the bus to allow devices to be attached. This worked really well and allowed for devices to be moved around when needed.

4-pin JST connector to the left: This was four wires to the button. To tell the vehicle to begin navigating under autonomous control, we used a metal momentary push button that illuminates when everything is online and happy. The human presses the button twice, and the car commences racing.

Big gray handle: This was the original forward and reverse knob that we reused to control the direction switch on the motor controller (two pins when shorted together caused one direction, when open caused the other direction).

The massive and poorly written control code for the Brain can be found here.

EEPROM for Waypoints

The SAMD21 does not have internal EEPROM. Because we needed to store GPS waypoints and other configuration data to non-volatile memory, we used an external I2C EEPROM. Yes, you can use something called emulated EEPROM on the SAMD21, but, every time you reprogram the board, you will overwrite anything previously stored in emulated EEPROM. The external EEPROM made it much easier to store and recall waypoints and settings without having to mash together in the main control code.

Control Electronics – Locomotion

Locomotion Controller PCB

Locomotion Controller hooked up

Note the polarized connectors and prodigious labeling! You DO NOT want to be guessing what gets plugged into where at 11 p.m. before race day. The Locomotion Controller code is available here, and the PCB layout here.

Because we eventually wanted this beast to be autonomous, we needed to put a controller in the middle between the throttle and the motor controller. We used an Arduino Pro Mini that did a huge variety of sensing and control:

  • Read the throttle
  • Output analog voltage to the motor controller
  • Read the brake switch
  • Read the steering position
  • Controlled the linear steering actuator
  • Read the human/robot control switch
  • Received and responded to control commands over I2C
Panic button and third switch

Don’t panic

The controller would monitor the rocket switch and brake switch. If a human ever pressed the brakes or turned off the rocket switch, the controller would go into safety shutdown and ignore any commands from the brain.

12V linear actuator on desk

Steering was controlled using a 12V linear actuator over-voltaged to 24V for extra speed. Two relays controlled the forward/backward motion.

Trimpot on rack and pinion steering

Steering position was obtained by cutting a hex wrench to about 1” and inserting that wrench into the bolt that rotates with the wheel. The wrench was then connected to a 10k trimpot using adhesive-lined heat shrink — this trick is known as the ”poor man’s coupler:” a 3-wire ribbon connected the trimpot back to the locomotion controller. It worked well, but we had to keep the analog signal wire away from the power bus; otherwise, bad noise got into the ADC readings.

Actuator on chassis

Chassis with the Batmobile raised to see the steering actuator

For future vehicles, we’re going to change this setup. It worked well enough, but once the bolt connected the actuator to the steering, you couldn’t drive the car; only the computer could. So rather than driving the car to the start line, we had to carry this 75lb beast. So painful. In the future, we plan to find a back-drivable actuator or maybe drive-by-wire.

Control Electronics – Displays

Throttle and displays

Throttle and displays

We cut notches in a 1” tube of PVC and mounted two displays in the Batmobile. The center display is the power meter. Nearly every A+PRS and PRS competitor used these super low-cost power meters to show the battery voltage. We had some issues with it, but it worked well enough. In the end, we noticed the drop in vehicle speed (indicating battery drain) long before we noticed the display was indicating a lower pack voltage. But, it did help us make decisions about when to pit (never!) because the nominal 48V pack voltage was dropping down to 42V where we could begin to damage the SLA.

The display on the right is the 20×4 character debug LCD. It’s basically a souped-up version of our 20×4 SerLCD display (it’s a prototype product, coming soon to a theater near you!).

Control Electronics – Sensors

GPS and compass connected to SAMD21

GPS+Compass connected to SAMD21

The Sensor Combinator is a SAMD21 Mini that monitors a GPS receiver and an I2C compass. We decided to use a SAMD21 because it can be configured to have multiple hardware serial and I2C ports. This is needed if you want to isolate I2C devices from the main bus. We wanted the Brain to ask for the heading and get the heading; the Sensor Combinator took care of the low-level I2C function of the compass and heading calculations. Similarly, the Combinator listened to the serial stream from the u-blox based GPS module and parsed out all the needed Latitude/Longitude/SIV information.

The code for the Sensor Combinator can be found here.

Control Electronics – Lasers

Batmobile with top off

Laser tape measures seen on the front of the car, wrapped in foil

We hacked three laser tape measures in order to get distance to any objection front, left or right of the car. Laser tape measures are getting cheaper, and while the read rate (3Hz at the best of times) is not great for LIDAR, it’s fast enough for basic, low-cost autonomy.

Lasers wired to controller

Laser Controller at front of car

Unfortunately, the laser tape measures threw off enough RF to interfere with our GPS module, so we wrapped the lasers in foil. These sensors deserve their own tutorial, which will be written soon.

PCB with connectors

Laser Controller with labels

Again we chose the SAMD21 Mini to help us control and combine the serial information coming from the three sensors. The Laser Controller would send the pertinent control strings to the tape measures and monitor the responses, combining them into distances for left/right/center. The Brain would request these values from the Laser Controller over I2C.

Note the prodigious amounts of labels and polarized connectors (JSTs work great!). This system required lots of debugging but worked well because we were able to quickly disconnect and reconnect various aspects of the system.

The code for the Laser Controller can be found here.

Problems

As with any project, we had a large number of problems and hurdles to overcome along the way. Here are a few that really hurt.

** EMI and GPS **

The Laser tape measures caused significant interference with GPS reception. We eventually moved the GPS module to the rear of the car, which improved positional accuracy. However, the motor caused interference with the compass.

** DC Motor EMF **

DC motors produce a ton of electromagnetic noise. We originally had the 48V battery powering the entire car. However, when the motor would kick on, it would cause enough ripple to make the Brain glitch and reset. We tried powering the I2C bus separately, but, because the Locomotion Controller needed to be attached to the motor controller, a GND connection had to be shared. The noise eventually found its way over the I2C bus. In the future we will optically isolate the I2C bus.

** Lack of EEPROM **

Because the SAMD21 doesn’t have internal EEPROM, we were unable to store GPS waypoints on the board. We fixed this by using an I2C-based EEPROM.

** Switching Steering Between Driver/Driverless **

It was difficult to attach and detach the linear actuator from the rack and pinion steering. Once the actuator was attached to the steering, a driver could not actively steer (for example, to the starting line). This could be fixed with a different actuator that could be back-driven, or we could go full monty and detach the steering column from the steering and have it control a trimpot that, in turn, controls the linear actuator (drive by wire).

Tips / Best Practices

Pig tails in air in a turn

Tip 1) Start early — These vehicles take a large amount of time. Get together with friends and start hacking. It’s a great labor of love, and drifting in a 15mph go-kart will make you giggle.

Tip 2) Get reverse — Get a motor controller with reverse. It will make it so you can drive your car where you want it instead of carrying your car where you need it.

Tip 3) Use connectors! — I’ve written about using connectors a few times. Use polarized connectors and a label maker to make it clear what plugs in where.

Tip 4) Size your motor and motor controller correctly — We blew our motor controller because it was underrated. A friend of ours smoked his motor because he was pushing too much current. Pick your system voltage and current, and then double the ratings wherever you can.

Tip 5) Beware of interference — These vehicles can pull 30 amps or more when accelerating, which can cause large electromagnetic fields. Keep unshielded cables and sensitive sensors away from power wires.

Tip 6) Wireless control and sensor logging — After you pick up your 75lb vehicle and drag it to the start line for the fifth time, you’ll understand the need for remote control. Create a wireless system that allows you to take over control of the vehicle from afar so you can drive it where you need it. And transmit the sensor data so you can see what the vehicle is doing.

Nathan with pigtails in Batmobile
SparkFun JetBot AI kit –  monteringsinstruktioner

SparkFun JetBot AI kit – monteringsinstruktioner

Assembly Guide for SparkFun JetBot AI Kit

Introduction

SparkFun’s version of the JetBot merges the industry leading machine learning capabilities of the NVIDIA Jetson Nano with the vast SparkFun ecosystem of sensors and accessories. Packaged as a ready to assemble robotics platform, the SparkFun JetBot Kit requires no additional components or 3D printing to get started – just assemble the robot, boot up the Jetson Nano, connect to WiFi and start using the JetBot immediately. This combination of advanced technologies in a ready-to-assemble package makes the SparkFun JetBot Kit a standout, delivering one of the strongest robotics platforms on the market. This guide serves as hardware assembly instructions for the two kits that SparkFun sells; Jetbot including Jetson Nano & the Jetbot add-on kit without the NVIDIA Jetson Nano. The SparkFun JetBot comes with a pre-flashed micro SD card image that includes the Nvidia JetBot base image with additional installations of the SparkFun Qwiic Python library, Edimax WiFi driver, Amazon Greengrass, and the JetBot ROS. Users only need to plug in the SD card and set up the WiFi connection to get started.

Completed SparkFun Jetbot

Note: We recommend that you read all of the directions first, before building your Jetbot. However, we empathize if you are just here for the pictures & a general feel for the SparkFun Jetbot. We are also those people who on occasion void warranties & recycle unopened instructions manuals. However, SparkFun can only provide support for the instructions laid out in the following pages.

Attention: The SD card in this kit comes pre-flashed to work with our hardware and has the all the modules installed (including the sample machine learning models needed for the collision avoidance and object following examples). The only software procedures needed to get your Jetbot running are steps 2-4 from the Nvidia instructions (i.e. setup the WiFi connection and then connect to the Jetbot using a browser). Please DO NOT format or flash a new image on the SD card; otherwise, you will need to flash our image back onto the card.

If you accidentally make this mistake, don’t worry. You can find instructions for re-flashing our image back onto the SD card in the software section of the guide

The Jetson Nano Developer Kit offers extensibility through an industry standard GPIO header and associated programming capabilities like the Jetson GPIO Python library. Building off this capability, the SparkFun kit includes the SparkFun Qwiic pHat for Raspberry Pi, enabling immediate access to the extensive SparkFun Qwiic ecosystem from within the Jetson Nano environment, which makes it easy to integrate more than 30 sensors (no soldering and daisy-chainable).


The SparkFun Qwiic Connect System is an ecosystem of I2C sensors, actuators, shields and cables that make prototyping faster and less prone to error. All Qwiic-enabled boards use a common 1mm pitch, 4-pin JST connector. This reduces the amount of required PCB space, and polarized connections mean you can’t hook it up wrong.


Materials

SparkFun Jetbot parts

The SparkFun Jetbot Kit contains the following pieces; roughly top to bottom, left to right.

PartQty
Circular Robotics Chassis Kit (Two-Layer)1
Lithium Ion Battery Pack – 10Ah (3A/1A USB Ports)1
Ball Caster Metal – 3/8″1
Edimax 2-in-1 WiFi and Bluetooth 4.0 Adapter1
Header – male – PTH – 40 pin – straight1
2 in – 22 gauge solid core hookup wire (red)1
Shadow Chassis Motor (pair)1
Jetson Dev Kit (Optional)1
SparkFun JetBot Acrylic Mounting Plate1
SparkFun Jetbot image (Pre Flashed)1
Leopard Imaging 145 FOV Camera1
Screw Terminals 2.54mm Pitch (2-Pin)2
SparkFun Micro OLED Breakout (Qwiic)1
SparkFun microB USB Breakout1
SparkFun Serial Controlled Motor Driver1
Breadboard Mini Self-Adhesive Red1
SparkFun Qwiic HAT for Raspberry Pi1
SparkFun JetBot Acrylic sidewall for camera mount2
SparkFun JetBot Acrylic Camera mount & 4x nylon mounting hardware1
Qwiic Cable – 100mm1
Qwiic Cable – Female Jumper (4-pin)1
Wheels & Tires – included as part of circular robotics chassis2
USB Micro-B Cable – 6″2
Dual Lock Velcro1
SparkFun Jetbot included hardware

The SparkFun Jetbot Kit contains the following hardware; roughly top to bottom, left to right.

PartQty
Hex Standoff #4-40 Alum 2-3/8″3
Standoff – Nylon (4-40; 3/8in.)10
1/4″ Phillips Screw with 4-40 Thread20
Machine Screw Nut – 4-4010
Circular Robotics Chassis Kit (Two-Layer) Hardware1

Recommended Tools

We did not include any tools in this kit because if you are like us you are looking for an excuse to use the tools you have more than needing new tools to work on your projects. That said, the following tools will be required to assemble your SparkFun Jetbot.

  • Small phillips & small flat head head screwdriver will be needed for chassis assembly & to tighten the screw terminal connections for each motor. We reccomend the Pocket Screwdriver Set; TOL-12268.
  • Pair of scissors will be needed to cut the adhesive Dual Lock Velcro strap to desired size; recommended, but not essential..
  • Soldering kit for assembly & configuration of the SparkFun Serial Controlled Motor Driver – example TOL-14681
  • Optional– adjustable wrench or pliers to hold small components (nuts & standoffs) in place while tightening screws; your finger grip is usually enough to hold these in place while tightening screws & helps to ensure nothing is over tightened.A Note About Directions

When we talk about the ”front,” or ”forward” of the JetBot, we are referring to direction the camera is pointed when the Jetbot is fully assembled. ”Left” and ”Right” will be from the perspective of the SparkFun Jetbot.

Front of Jetbot

1. Circular Robotics Chassis Kit (Two-Layer) Assembly

If you prefer to follow along with a video, check out this feature from the chassis product page. You do not need to use the included ball caster as a larger option has been provided for smoother operation.

Start by attaching the chassis motor mount tabs to each of the ”Shadow Chassis Motors (pair)” using the long threaded machine screws & nuts included with the Circular Robotics Chassis Kit.

Hobby motor and mount

Fit the rubber wheels onto the hubs, install the wheel onto each motor, & fix them into position using the self tapping screws included with the Circular Robotics Chassis Kit.

hobby motor with wheel

Install the brass colored standoffs included with the Circular Robotics Chassis Kit; two in the rear and one in the front. The rear of the SparkFun Jetbot will be on the side of the plate with the two ”+” sign cut outs. The rear of the motor will be opposite the wheel where the spindle extends. This orientation ensures the widest base & most stable set up for your Jetbot.

motor mount to plate

The motor mounts fit into two mirrored inlets in each base plate as shown. Install the motors opposite of one another.

install standoffs

Depending on how you install the motor mounts to each motor will dictate how the motor can be installed on the base plate. Note: Do not worry about the motor orientation as you will determine proper motor operation in how you connect the motor leads to the SparkFun Serial Controlled Motor Driver. Notice how in the picture below one motor has the label facing up, while the other has the label facing down.

both motors on plate and standoffs

Place the other circular robot chassis plate on top of and align the two ”+” and the motor mount tab recesses. Hold the sandwiched chassis together with one hand and install the remaining Phillips head screws included with the Circular Robotics Chassis Kit through the top plate & into the threaded standoffs.

install top plate

Your main chassis is now assembled! The Circular Robotics Chassis Kit also contains a very small caster wheel assembly, but we have included a larger metal caster ball to increase the stability of the SparkFun Jetbot. We will cover the installation of this caster ball later in the tutorial.

screw install top plate

Utilize three of the included 1/4 in 4-40 Phillips Screws through the top chassis plate with threads facing up & install the 2-3/8 in #4-40 Aluminum Hex Standoff until they are finger tight.

install tall standoffs

The aluminum stand offs should be pointing up as shown below.

Standoff installed

The SparkFun JetBot acrylic mounting plate is designed to have two of these aluminum standoffs in the front & one in the rear. We recommend the rear standoff on the left side of the chassis (as shown) so the 6 in microB usb cables that will be installed later can more easily span the gap needed to power the JetBot.

all standoffs installed

Un-package the 3/8 in Metal Caster Ball and thread the mounting screws through all pieces as shown. Note the full stack height will help balance the Jetbot in a stable position.

caster wheel assembly
more caster wheel assembly

Install the caster wheel using the Phillips head screws and nuts included with the 3/8 in caster ball assembly. The holes on the caster assembly are spaced to fit snug on the innermost segment of the angular slots near the rear of the lower plate on the JetBot chassis. Again, hand tight is just fine. Note: if you over tighten these screws it will prevent the ball from easily rotating in the plastic assembly. However, too loose and it may un-thread; go for what feels right

caster install to chassis

After you have installed the caster & aluminum standoffs, thread the motor wires through the back of the chassis standoffs for use later.

Completed chassis

2. Camera Assembly & Installation

Unpackage the Leopard Imaging camera & align the four holes in the acrylic mounting plate with those on the camera.

Note: ensure that the ribbon cable is extending over the acrylic plate on the edge that does not have mounting holes near the edge; as shown below.

Place all four nylon flathead screws through the camera & acrylic mounting plate prior to fully tightening the nylon nuts. This will ensure equal alignment across all four screws. Tighten the screws while holding the nuts with finger pressure in a rotating criss cross pattern; similar to how you tighten lug nuts on a car rim.

Camera to mount

Align one acrylic sidewall with the camera mounting plate as shown below ensuring that the widest section of the sidewall is oriented to the top of the camera mount where the ribbon cable extends.

camera sidewall install

Apply even pressure on each piece until they fit together. Note: these pieces are designed to have an interference fit and will have a nice, satisfying ”click” when they fit together.

camera sidewall complete

Repeat this process on the other side to fully assemble the camera mount.

fully assembled camera

The camera mount should now be installed to the SparkFun Jetbot acrylic mounting plate using the overlapping groove joints. Ensure that the cut out on the acrylic mounting plate is facing towards the front/right of the Jetbot as shown. This will ensure that there is plenty of room for the camera ribbon cable to pass around the assembly and up to the Jetson nano camera connector.

camera mount to plate

Install four of the nylon standoffs to the top of the SparkFun Jetbot acrylic mounting plate using four of the included 1/4 in 4-40 Phillips head screws as shown below.

Jetson Nano standoffs to plate
all standoffs on plate

Utilize three more of the 1/4 in 4-40 Phillips head screws to install the SparkFun Jetbot acrylic mounting plate to the aluminum standoffs extending from the Two-layer circular robotics chassis as shown below.

install camera plate to chassis

3. Motor Driver Assembly & Configuration

To get started, make sure that you are familiar with the SparkFun Serial Controlled Motor Driver Hookup Guide.

We also recommend a detailed review of the Hardware Overview of the SparkFun Serial Controlled Motor Driver Here.

Annotated front SparkFun Serial Controlled Motor Driver

You will need to solder both triple jumpers labeled below as ”I2C pull-up enable jumpers” as the SparkFun pHat utilizes the I2C protocol. The default I2C address that is used by the pre-flashed SparkFun Jetbot image is 0x5D which is equavalent to soldering pad #3 noted as ”configuration bits” on the back of the SparkFun serial controlled motor driver; see below. You will need to create a solder jumper on pad #3 only for the SparkFun Jetbot Image to work properly.

Annotated rear SparkFun Serial Controlled Motor Driver

Layout of jumpers on the Serial Controlled Motor Driver.

Properly Jumpered SCMD

Jumper 3 of theConfiguration Bitsproperly soldered.

Your completed Serial Controlled motor drive should look somewhat similar to the board shown below.

  • The 2-pin screw terminals are soldered to the ”Motor Connections.”
  • Break off 4 Male PTH straight headers and solder into the ”Power (VIN) connection” points.
  • Break off 5 Male PTH straight headers and solder into the ”Expansion port” points. These will not be used, but will provide additional board stability when installed into the mini breadboard.
  • Break off 5 Male PTH straight headers and solder into the ”User port” points for connection into the included Female Jumper Qwiic cables.
completed motor driver
completed motor driver 2

Break off 5 Male PTH straight headers and solder into the breakout points on the SparkFun microB USB Breakout.

Install both the SparkFun Serial Controlled Motor Driver & the SparkFun microB Breakout board on the included mini breadboard so the ”GRD” terminals for each unit share a bridge on one side of the breadboard.

Utilize the included 2 in – 22 gauge solid core hookup wire (red) to bridge the ”VCC” pin for the SparkFun microB Breakout to either (VIN) connection point on the SparkFun Serial Controlled Motor Driver as shown below.

motor driver and usb to breadboard

Required power connections between the micro-USB breakout and the Serial Controlled Motor Driver.

motor driver and usb to breadboard

Competed assembly of the micro-USB breakout and Serial Controlled Motor Driver on the breadboard.

Utilize a small flat head screwdriver to loosen the four connection points on the screw terminals. When inserting the motor connection wires, note the desired output given the caution noted in section #1 of this assembly guide.

Note from section #1: Do not worry about the motor orientation as you will determine proper motor operation in how you connect the motor leads to the SparkFun Serial Controlled Motor Driver.

These connection points can be corrected when testing the robot functionality. If your Jetbot goes straight when you expect Jetbot to turn or vice versa, your leads need to be corrected.

motor cables to motor driver

Set this assembly aside for full installation later.

4. Accessory Installation to Main Chassis

Align the mounting holes on the SparkFun Micro OLED (Qwiic) with those on the back of the SparkFun Jetbot acrylic mounting plate. Install the Micro OLED using two 1/4 in 4-40 Phillips head screws and two 4-40 machine screw nuts.

qwiic oled to chassis
completed qwiic oled to chassis

Thread the ribbon cable of the Leopard imaging camera back through the acrylic mounting plate and half-helix towards the left side of the Jetbot.

camera ribbon cable threading

Install the Jetson Nano Dev kit to the nylon standoffs using four 1/4 in 4-40 Phillips head screws. Tighten each screw slightly in a criss-cross pattern to ensure the through holes do not bind during install until finger tight. Make sure you can still access the camera ribbon cable.

Jetson Nano install

Note: the camera connector is made from small plastic components & can break easier than you think. Please be careful with this next step.

Loosen the camera connector with a fingernail or small flathead screwdriver. Fit the ribbon cable into this connector and depress the plastic press fit piece of the connector to hold the ribbon cable in place.

camera attachment to Jetson Nano

Unpackage & install the USB Wifi adaptor into one of the USB ports on the Jetson nano Dev Kit. The drivers for this Wifi adaptor are pre-installed on the SparkFun Jetbot image. If you are making your own image, you will need to ensure you get these from Edimax.

USB wifi install to Jetson Nano

Align the SparkFun pHat with the GPIO headers on the Jetson Nano Dev Kit so that the pHat overhangs the right hand side of the Jetbot. For additional information on hardware assembly of the SparkFun pHat, please reference the hookup guide here.

Note: The heatsink on the Jetson Nano Dev Kit will only allow for one orientation of the SparkFun pHat.

PHat installation

Wrap the motor wires around the rear/left standoff to take up some of the slack; one or two passes should do. Peel the cover off the self adhesive backing on the mini breadboard you set aside at the end of section #3.

breadboard installation to chassis

Place the breadboard near the back of the Jetbot Acrylic mounting plate where there is good adhesion & access to all the components. Attach the (4-pin) Female Jumper Qwiic cable to the SparkFun Serial Controlled Motor Driver pins as shown. Yellow to ”SCL,” Blue to ”SDA,” Black to ”GND.”

breadboard placement on chassis and qwiic cable to motor driver

Daisy chain the polarized Qwiic connector on the other end of the (4-pin) Female Jumper Qwiic cable into the back of the SparkFun Micro OLED (Qwiic).

Qwiic cable installation

Using the 100mm Qwiic Cable attach the SparkFun Micro OLED front Qwiic connector to the SparkFun pHat as shown.

Qwiic install to PHat board

Cut the Dual Lock Velcro into two pieces and align them on the 10Ah battery & top plate of the Two-Layer Circular Robotics Chassis as shown below. Ensure that the USB ports on the battery pack are pointing out the back of the Jetbot. Additionally, the orange port (3A) will need to power the Jetson Nano Dev Kit & therefore will need to be on the right side of the Jetbot.

battery pack Velcro placement
Note high amp usb socket

Apply firm pressure to the battery pack to attach to the Jetbot chassis via the Dual Lock Velcro.

battery pack installation

Remove the micro SD card from the SD card adapter.

micro SD card

Insert the micro SD card facing down into the micro SD card slot on the front of the Jetson Nano Dev Kit. Please see the next three pictures for additional details.

install image into SD card slot on Jetson
Card in SD slot
Card in SD clost underview

The USB ports on the back of the 10Ah battery pack has two differently colored ports. The black port (1A) is used to power the motor driver via the SparkFun microB breakout. Utilize one of the 6 in micro-B USB cables to supply power to the microB breakout.

USB power motor drivers low amp
Note high amp usb socket

Note: Once you plug the Jetson Nano Dev Kit into the 3A power port, this will ”Boot Jetson Nano” which is not covered in detail until the links in section #5 of this assembly guide. Do not proceed unless you are ready to move forward with the software setup & examples provided by NVIDIA.

The orange port (3A) is used to power the Jetson Nano Dev Kit. Utilize the remaining 6 in micro-B USB cable to supply power to the Jetson Nano Dev Kit.

Final usb cable install

Congratulations! You have fully assembled your SparkFun JetBot AI Kit!

5. Software Setup Guide from NVIDIA

Attention: The SD card in this kit comes pre-flashed to work with our hardware and has the all the modules installed (including the sample machine learning models needed for the collision avoidance and object following examples). The only software procedures needed to get your Jetbot running are steps 2-4 from the Nvidia instructions (i.e. setup the WiFi connection and then connect to the Jetbot using a browser). Please DO NOT format or flash a new image on the SD card; otherwise, you will need to flash our image back onto the card (instructions below).

Your SparkFun Jetbot comes with a Pre-Flashed micro SD card. Users only need to plug in the SD card and set up the WiFi connection to get started.

  • The default password on everything (i.e. login/user, jupyter notebook, and superuser) is ”jetbot”.
  • We recommend that users change their passwords after initial setup. These are typically covered on the first boot of your Jetson Nano as detailed in the NVIDIA Getting Started with Jetson Nano walkthrough

Software Setup

The only steps needed to get your Jetbot kit up and running is to log into the Jetbot and setup your WiFi connection. Once that is done, you are now ready to connect to the Jetbot wirelessly. If you need instructions for doing so, you can use the link below.However, please take note of our instructions below. You will want to skip steps 1 and 5 to avoid erasing the image on the card or undoing the hardware configuration.NVIDIA JETBOT WIKI SOFTWARE SETUP

Instructions

  1. Skip step 1 of Nvidia’s instructions: It references how to flash your SD card, so feel free to skip to Step 2 – Boot Jetson Nano.

Note: Following Step 1 will erase the pre-flashed image and make a lot of extra work for yourself.

  1. Skip step 5 of Nvidia’s instructions: This step should already be setup on the pre-flashed SD card.

Get and install the latest JetBot repository from GitHub by entering the following commands

COPY CODEgit clone https://github.com/NVIDIA-AI-IOT/jetbot
cd jetbot
sudo python3 setup.py install

Note:Running sudo python3 setup.py install in the command line will overwrite the software modifications for SparkFun’s hardware in the kit.

Troubleshooting

In the event that you accidentally missed the instructions above, here are instructions to get back on track.

Re-Flashing the SD card

If you need to re-flash your SD card, follow the instructions from Step 1 Nvidia’s guide. However, download and use our image instead (click link below).DOWNLOAD SPARKFUN’S JETBOT IMAGENote: Don’t forget to uncompress (i.e. unzip, extract, or expand) the file from the .zip file/folder first. You should be pointing the ”flashing” software to an ~62GB .img file to flash the image (sparkfun_jetbot_v01-00.img) onto the SD card.

Alternatively, there are other options for flashing images onto an SD card. If you have a preferred method, feel free to use the option you are most comfortable with.

Re-Applying the Software Modifications

If you have accidentally, overwritten the software modifications for the hardware included in your kit, you will need to repeat Step 5 from Nvidia’s guide from the desktop interface (if you are comfortable performing the following steps from the command line, feel free to do so).

Skip steps 1 and 2: Plug in a keyboard, mouse, and monitor. Then log in to the desktop interface (if you haven’t changed your password, the default password is: jetbot).

Follow step 3: Launch the terminal. There is an icon on sidebar on the left hand side. Otherwise, you can use the keyboard short cut (Ctrl + Alt + T).

Follow step 4: However, before you execute sudo python3 setup.py install you will want to copy in our file modifications to the jetbot directory you are in.

  1. Begin by downloading our files (click link below).

DOWNLOAD MODIFICATION FILES

  1. Next, extract the file.
  2. Next, replace the files in the jetbot folder. The file paths must be the same, so make sure to overwrite files exactly.

Click on the icon that looks like a filing cabinet on the left hand side of the GUI. This is your Home directory. From here, you will need to proceed into the jetbot folder. There you will find a jetbot folder with similar files to the ones you just extracted. Delete the folder and copy in our files (you can also just overwrite the files as well).

  1. Now, you can execute sudo python3 setup.py install in the terminal.

Follow step 5: Finish up by following step 5. Now you are back on track to getting your Jetbot running again!

6. Examples

The ”object following” jupyter notebook example won’t work due to the required dependencies that had not been released by NVIDIA prior to the creation of the SparkFun JetBot image. These updates can be manually installed on your Jetson Nano with the JetPack 4.2.1 release.

Update: The engine generated for the example utilized a previous version of TensorRT and is therefore, not compatible with the latest release. For more details on this issue, check out the following GitHub issue.NVIDIA JETBOT WIKI EXAMPLES

Resources and Going Further

Now that you’ve successfully got your JetBot AI up and running, it’s time to incorporate it into your own project!

For more information, check out the resources below:

Need some inspiration for your next project? Check out some of these related tutorials:

Easy Driver Hook-up Guide

Get started using the SparkFun Easy Driver for those project that need a little motion.

Servo Trigger Hookup Guide

How to use the SparkFun Servo Trigger to control a vast array of Servo Motors, without any programming!

SparkFun 5V/1A LiPo Charger/Booster Hookup Guide

This tutorial shows you how to hook up and use the SparkFun 5V/1A LiPo Charger/Booster circuit.

Wireless Remote Control with micro:bit

In this tutorial, we will utilize the MakeCode radio blocks to have the one micro:bit transmit a signal to a receiving micro:bit on the same channel. Eventually, we will control a micro:bot wirelessly using parts from the arcade:kit!

Tips för bättre 3D-utskrifter med Cura

Cura är ett open-source slicer-program. Det är ursprungligen utvecklat av företaget Ultimaker som en slicer till deras 3D-skrivare, men fungerar lika bra till nästan alla andra 3D-skrivare på marknaden. Det är ett av de mest populära programmen för detta ändamål.

För att skriva ut saker i en en 3D-skrivare behövs ett så kallat slicer-program. Det är ett program som gör om en STL-fil till G-code som 3D-skrivaren kan tolka. Slicern skivar upp 3D-modellen i olika lager där G-coden bestämmer var det ska läggas ut filament och hur.
Här är ett antal parametrar man kan justera i inställningarna för sin 3D-utskrift:

  • Layer height: Höjden på varje lager i utskriften
  • Wall thickness: Tjockleken på väggarna i utskriften
  • Top/bottom thickness: Tjockleken på “tak” och “golv” i utskriften
  • Infill density: Hur mycket av insidan ska täckas upp med material?
  • Printing temperature: Temperatur på munstycke – beror på vilket material vi väljer
  • Build plate temperature: Temperatur på byggplatta – beror på vilket material vi väljer
  • Travel speed: Hur fort munstycket rör sig när det inte extruderar plast
  • Enable print cooling: Om vi vill kyla plasten med “part cooling fan” när det kommer ut
  • Build plate adhesion: Olika metoder för att få bättre fäste vid byggplatta
  • Enable supports: Om det automatiskt ska genereras stödstrukturer
  • Support placement: Vart stödstrukturer ska genereras
  • Support density: Hur mycket stödstrukturer ska genereras
  • Support overhang angle: Vart stödstrukturer ska genereras
  • Print speed: Utskriftshastighet – hur fort munstycket rör sig när det extruderar plast

I nedanstående filmklipp visar Chuck dig tre Cura Slicer-inställningstrick för nybörjare som han använder på sina ENDER 3 och CR-10 Mini hela tiden. Dessa Cura-tricks är särskilt användbara för alla som precis kommit igång med 3D-printing.

3 Cura Slicer Setting Tricks For Beginners (8:19)

Support eller stödstrukturer

Om ett 3D-objekt du vill skriva ut har delar med överhäng behöver du använda supportmaterial eller s k stödstrukturer. Det finns olika sätt att lägga till stödstrukturer till ett en 3D-modell. Hur du ställer in Cura Tree Supports (trädstöd) och Simple Support och vilka inställningar du kan göra hittar du i nedanstånde avsnitt av Filament Friday med Chuck. Han använder en enkel testutskrift för att se vilket Cura-stöd som fungerar bäst och varför. Han visar hur enkla de är att ta bort och hur bra utskriften ser ut när du är klar.

CURA – Tree Supports vs Standard Supports (8:27)

Med en plugin till Cura går det att skapa mer precisa manuella stödstrukturer bara just där du vill ha dem, så att du kan spara plast och snabba upp utskrifterna jämfört mot att använda de automatiska verktygen.

Custom Manual Supports in Cura 4.3 (7:45)

Build plate adhesion – Skirt, Brim and Raft


Build plate adhesion – Skrit, Brim, Raft (3:16)

How to get your 3d printed parts to stick to the bed and avoid curling/warping

(15:31)