I’m heading down to the 20th Annual Western Canadian Robot Games a little later today, but the ‘rover won’t be competing 🙁
The rover isn’t mobile yet, after I found the long cables from the body to the steering servos and the motor encoders were picking up to much noise from the motor power wiring, and I’m not done with assembling and coding the circuit boards to move those functions out to the wheels.
I did make some other progress, you can see here I’m fiddling with pullup resistors to get the I2C bus ‘just right’. The water bottle on the right gives a sense of scale; it’s about the same size as Sojourner, although the wheels don’t fold up for a trip to Mars…
That mass of wires on the top? All breadboard-bound… I’ve learned the hard way that if it doesn’t work on a breadboard, there is no way doing a cleaner job on a soldered protoboard is going to make it ‘better’. Here is the view of the rats-nest:
The other big things done (or tested) are adding a connector to the Adafruit Ultimate GPS + Logger board, so I can attach both it’s host Arduino Leonardo and the SD writer as SPI slaves to the Max32, instead of having the SD card as an SPI slave to the Leonardo. The SPI code examples for the SD library compiled and I was reading and writing to the SD card from the Chipkit Max32 on the first try, so that’s a relief. Now I can start logging to the SD, and storing the menu system for the hand controller in a file on the SD card instead of hard-coded in the Max32.
With another whole year until the 2014 games I might start a bit simpler and eliminate some of the additional Atmel chips and just use the Max32 with a LOT more stuff on it’s I2C bus. The big reason is that with such short summers here in Calgary I’d like to spend most of the time doing test drives outdoors, and not fiddling with custom PCB’s – I can save that for the winter.
Look for some driving videos over the next two weeks, and hopefully I’ll have a few good snapshots of the Robot Games from today in the next post.