A parts list for all of the CHRP4 circuit board components has been added to the Hackaday project page, and a public list of parts is also available on Digi-Key which lists all of the Digi-Key part numbers and costs: https://www.digikey.ca/en/mylists/list/SHTZL28E58

While all of the parts are included in both parts lists, certain parts may not be required for specific builds. The Education Starter configuration of CHRP4 is built with a minimal subset of parts to get students programming quickly.

Building CHRP4 into a line-following, obstacle-sensing, or Sumo robot requires nearly all of the components – the primary difference between the two is the line/floor sensors. A line-following robot uses a single IR LED, and two IR phototransistors, while a Sumo robot uses two IR LEDs and two IR phototransistors.

The IR demodulator is optional for all configurations, and allows CHRP4 to be controlled using the UBMP4 circuit or a TV remote control.