Tuesday, January 26, 2021

Lego Robotics: SPIKE Prime and Mindstorms

It's a confusing time for educators who use Lego robotics. The end of 2020 saw the release of a new Lego robotics ecosystem: SPIKE Prime. Or is it called Mindstorms? Or 51515? Or Robot Inventor?


I guess it's "all of the above" but it depends on which application you'll be using it in. SPIKE Prime seems to be geared towards the school or organization setting whereas the Mindstorms and Robot Inventor line looks more retail or consumer based, especially with the model number: 51515. They contain similar Technic-based components and share the same hub (or "brick") unit but differ in number of components and motors and sensors.

However, don't be fooled by the incremental set number, this new line is not intended as a replacement or upgrade from the 31313 EV3 line. It sits in between WeDo 2.0 and EV3, according to Lego:


I have never used WeDo but my school has invested heavily in EV3 so I was curious about the new line and how it may affect our scope and sequence of robotics. I can't imagine replacing our EV3 investment right now, we just have too many parts and components and resources to justify that so any replacement would be years away. However, could SPIKE/Robot Inventor serve as an addition to our primary or middle years program?

I've had a few days to play with the 51515 Mindstorms Robot Inventor set and can give my first impressions. It's easiest to compare the new line to EV3 since they share similar ethos and it's the line I'm most familiar with. Some of the major differences to EV3 for the brick or hub include:
  • No LCD display; replaced by a 5x5 array of monochrome LEDs
  • Smaller and lighter
  • Includes a built-in accelerometer and gyroscope
  • Smaller storage memory but I haven't done enough programs to test the limits
  • Hubs cannot connect together
  • Included rechargeable battery pack!
  • Speaker is awful and can't play MP3s or WAV files

I never minded the LCD display on the EV3 and the new LED pixel display take some getting used to. Programs are loaded, for example, by a pixely number displayed requiring you memorize files. This would be disastrous in a classroom setting, however it's Lego's intentions to depend entirely on the Mindstorms app where you can have a bit of organization. I'm not aware of any classroom management component of the app so I hope there's a way for educators to manage the logistics of multiple classes and projects.

Speaking of the app, it's crashed or hung multiple times for me which isn't very encouraging. I also had problems updating the firmware on the hub and motors on first boot. I had to pull the battery and restart the process three times, each time thinking I had bricked the brick. I also had some connection issues until I changed the charging cable to the included one and things worked much better. Side note: it's still a micro-USB connection which is odd, I would think a USB-C connection would be more future-proof.

I haven't checked out any SPIKE Prime teaching resources but the Mindstorms app is very consumer-geared. There are no paper assembly instructions or ideas including the box. Instead, videos and multi-stage projects launch you right into the building via the app. I liked the variety of first projects, they definitely show you how the different Technic components work to structurally support and utilise the motors. I have only used the iPadOS version but the block coding components seem sound and apparently there is tight Scratch integration. I haven't tried microPython yet.

Cables, sensors and motors are new and not compatible with EV3. They may be compatible with a certain Technics line but I'm not certain. This alone would prevent us from a complete replacement, we have hundreds of these components that would require repurchase. The motors do have an absolute position mark and the app handily reminds you to calibrate the motors/servos each time which is nice. I am very nervous about the fixed wires, however. Instead of the pluggable cables of EV3 each motor and sensor has a permanent cable affixed. If the cable breaks then the entire motor or sensor needs replacing instead of just the wire.

All-in-all it's a pretty smooth lineup of new components. It really does seem very closely related to EV3, however, which makes it an odd introduction or middle-ground. There's not much here, outside of the app, to make it that much more easy for young builders; I feel like you can just jump straight to EV3. I've seen some great simple resources produced for EV3 that make building and programming easy for younger students so that would be more cost-efficient.