Which Romi kit + accessories do I need for 2 distance sensor, precision straight driving and turning

New to Pololu products.

Coming from FLL experience into our first foray into Arduino-controlled robotics for Science Olympiad Division C Robot Tour event. The task is to build a compact robot 2-wheel + omnidirectional bearing/caster robot that can traverse a maze composed of 2x4 sections that form occasional walls. Run time is between 55 and 85 seconds, with a need for precise pivot turning, precise straight driving, accurate wall distance detection, and up to ~25 cm per second speeds.

Some potentially challenging restrictions: It cannot use rechargeable batteries, it must use AA, non-rechargeable batteries.

The other requirements are that it (a) uses python for coding (so we can reuse some existing code/logic from EV3/micro-python) (b) it must be able to run “autonomously” once started using a push button on the robot, relying on code downloaded to the device.

The previous EV3 kit we were using was perfect for this, but the EV3 motors are getting worn out and it’s time to upgrade.

I’m looking for advice on (a) which accessories do I need to order vs. what comes with the base kit, (b) I’m assuming there’s no special requirements for using AA batteries. (c) are there readily available ToF distance sensors that can work with this setup? (d) what sensor should be used for precision angle tracking to ensure precise turns?

Hello.

We do not have any robot kits specifically intended for that competition. It sounds like you already might be looking at the Romi chassis and accessories, which could be a good starting point since the Romi chassis have an array of mounting holes you could use for attaching sensors and electronics. However, please keep in mind that we do not currently have any microcontroller boards intended specifically for use with the Romi chassis that support Micropython. We do have an Arduino compatible control board though, the Romi 32U4 Control Board (which has built-in motor drivers, an accelerometer, and a gyro) and I expect you would be able to find a similar plethora of resources for Arduino programming as for MicroPython.

As for other parts you would need, encoders are almost always helpful (especially for autonomous programming), and if you decide to use your own microcontroller board, then I would recommend the Motor Driver and Power Distribution Board for Romi Chassis as well as adding a MinIMU-9 Gyro, Accelerometer, and Compass if you want to use it to help make accurate turns.

As for detecting the walls, there are several ways you could go about that, but I would specifically recommend looking at the Pololu Digital Distance Sensors and the different ST Time-of-Flight (ToF) distance sensor carriers. In general, the digital distance sensors will be easier to use, but offer fewer features and less flexibility. Alternatively, our OPT3101 based 3-channel wide FOV ToF senor, or our more basic 8 kHz IR proximity sensors might be good options as well.

- Patrick