What follows are notes from the build of the KRZ03, a Mecanum-wheeled robot.

It uses parts from the KRZ01 and KRZ02 robots and therefore supercedes (replaces) them. The most recent version is using a Raspberry Pi Zero 2 W, a Pimoroni Motor 2040 and TinyFX (for LEDs and sound effects).

The KRZ03 robot

This photo shows an earlier version using a pair of PiconZero motor controllers that were used on the KRZ02, connected with a Mini Black Hat Hack3r. After contacting 4Tronix, they sent a customised Picon Zero that uses a different I2C address so that it's possible to use two on this robot without bus contention. A simpler alternative would have been to use the PiBorg ZeroBorg Motor Controller, which has four motor controllers as well as a 1.5A regulated power supply.

Earlier version of the KRZ03 robot

The Raspberry Pi GPIO Pinout (courtesy pinout.xyz)

Hardware#

The specific features of the KRZ03 robot's hardware include:

• Raspberry Pi Zero 2 W as main controller
• Pimoroni Motor 2040 as the motor controller
• 4x Pololu N20 250:1 Micro Metal Gearmotors (HPCB 6V #5197) with built-in encoders
• 4x JST SH 6 pin cables to connect the motors to the controllers ("reversed" or "opposite")
• Pimoroni Breakout Garden for Raspberry Pi, 6 slots
• Pimoroni Tiny FX W for control of audio and LED lights
• PIR Stick for Tiny FX
• Pimoroni Adhesive Backed Mini Speaker 8Ω (1W)
• subminiature SPDT toggle switch to switch between an external supply and the battery
• toggle switch and a pushbutton connected to GPIO pins as input devices
• chassis made from 3mm and 5mm black Delrin plastic, using LynxMotion M3 spacers
• set of four Nexus Robot 48mm Steel Mecanum Wheels
• Pololu 5V, 5.5A Step-Down Voltage Regulator D36V50F5
• Makita 12V 2Ah power tool battery
• Makita YL00000003 12V max CXT Power Source (a power clip compatible with the battery)
• 19V laptop power supply as an external power supply

Sensors include:

• 3x Pololu Distance Sensors with Pulse Width Output, 50cm Max (#4064)
• PAA5100JE Near Optical Flow SPI Breakout
• ICM20948 9DoF Motion Sensor Breakout mounted on a 6x10x140mm Delrin mast
• VL53L5CX 8x8 Time of Flight (ToF) Array Sensor Breakout
• VL53L1X Time of Flight (ToF) Sensor Breakout
• pair of 5x5 RGB Matrix Breakouts
• 11x7 LED Matrix Breakout
• ADS1015 used for monitoring the battery and regulators
• Adafruit CH334F Mini 4-Port USB Hub Breakout

The above summary may also be found on the GitHub page for the project.

Software#

The KRZOS operating system may be found on its GitHub repository at: https://github.com/ifurusato/krzos