Raspberry Pi as a Brain

For Christmas my kids got me the Vex Motorized Robotic Arm and I was pretty impressed with the assembly… reminded me of good old Erector Set kits. Once together I got quickly bored and hacked it so I can control the arm with my Raspberry Pi vs. the little switch box that comes with the kit. Pretty simple feat with Python, GPIO modules, a pair of L298N DC motor bridges and some light soldering. You can check it out here --> https://youtu.be/ThJFJLE-gqc

I got a little crazy a bought 8 different Vex kits off the store shelves since they were on clearance. Then curiosity got the best of me, I didn’t realize how big the Vex kits are and what’s available until I did lots of research online. Never the less, with all parts combined I pretty much have the bigger Vex IQ kits with more specialty parts (I did order tank treads and gear add-ons). I’ll post some of my builds in the right discussion bucket.

On another note, I keep looking at the Vex Brain and the Motors/Sensors and came to a conclusion… I’m going to build everything with the RPi to keep it more interesting and challenging.

Are there other “OG” (Original Geek) Hackers that are interesting in brainstorming and knowledge sharing to allow folks to use Raspberry Pi’s vs the Vex Brain system?

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So are you thinking more in the “Pi with HexBug motors” camp or want to go fancy with “Pi with VEX IQ motors”?
VexIQ motors are much smarter, work independently and get controlled over I2C. The link-layer protocol is well documented, but the register map used to control/query the motor isn’t.

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Well, what I have now is 8 Hexbug motors and a few of their IR distance sensors based on purchasing several kits before discovering the Vex IQ larger robotic kits. I do want to score the bump sensors that come with the Ant. The Hexbug motors/sensors are indeed very basic and wire into the RPi following standard GPIO practices. – so, Hexbug RPi Brain takeover will be easy and I have quite a few things already done, including a Pi case that mounts to Vex gear and phone charger battery packs to power the Pi as well as the motors/sensors. I just started working on the controller piece, scored a wireless Logitech game controller and how-to’s for Wii controller adoption.

I was looking at the Vex IQ motors and sensors and was curious how they work. Since you pointed out they’re I2C I did some research. The RPi does support I2C interaction and there is Python modules for interaction. There is also a register scan to reveal all connected devices using I2C. For connectivity, there are a few Pi HATS that can be used, this one http://www.robotshop.com/en/dc-servo-motor-driver-hat-raspberry-pi.html seems to be the most promising. It can support 16 motors or other devices and is stackable to support 256 devices… one could build a C3-PO unit. I guess I’ll bite the bullet and order the Vex IQ bundle to reverse engineer and do compare/contrast on performance and functionality between it and a Pi.