Bot doesn't go in a straight line

[PixelBoxel]

add encoders http://shop.pimoroni.com/products/reflective-ir-sensor-with-470-and-10k-resistors
and count how much the wheels are turning

[mr-eggleton]

Have wired in 1 encoder.
However it looks like there is an error in Explorer Hat library pimoroni/explorer-hat#2

[mr-eggleton]

Option 1:
run motor.one at 95 (multply all speeds by 0.95) and adjust motor.two (starting at 0.95 multiplier) to get the spoke counts to match

[mr-eggleton]

Option 2:
both start at 100 and slow the faster one until they match. if the one that isn't 100 is now the slower one speed it up.