Robo HAT MM1

An open source robotics and automation controller for Raspberry Pi.

May 23, 2019

Donkey Car Improvements and Maker Faire

Hello Followers!

We have had a big week of announcements and events. We visited Maker Faire Bay Area, hosted a small meet-up, experimented with RC controllers and much more…

Read on in the update to see what you missed during the week. Don’t forget to get your early bird offer for the Robo HAT MM1 Starter Kit - while stocks last!

With three weeks to go in the campaign, we are working very hard.

Reminder: Early Bird Offers Increased, Lower Price

We increased the number of early bird offers available for the Maker Faire Weekend. There are still some available now, and no more will be released during this campaign.

We also changed the price of the board to $39 USD. This is the lowest we can do with a manufacturing run of 200 boards. We changed the price as we re-evaluated why we started the project in the first place.

The Robo HAT MM1 has always been a way to make the Donkey Car Platform easier to use. This platform is a low-cost autonomous car hardware and software package aimed at helping people learn the basics of machine vision / AI; then seeing them take the ideas of the car and use them to solve real world problems. That is the goal that we want to see be a reality with the Robo HAT. People taking cheap, powerful hardware and solving real world problems.

We really want to see as many people as possible using the Robo HAT in different applications and then going on to solving real world problems. Whether it be autonomous cars, delivery drones, medical monitoring equipment, saving the environment or something yet to be thought of - we saw the Robo HAT MM1 as a way to make this happen - through accessible, powerful hardware that anyone can buy and use.

After taking all of this into consideration, we decided to lower the price to the minimum possible so that the community can build new tech and solve problems!

Maker Faire

We received so much support from everyone at Maker Faire Bay Area this time. Unfortunately it was raining for two days but that didn’t dampen the support and love of the Robo HAT MM1. The feedback we got back from Maker Faire was that the IMU is one of the defining features of the board. Everyone wants to use the IMU for improving the Donkey Car Platform.

Thank you for everyone who came down and chatted with us and for the support of the Donkey Car and DIY Robo Car teams.

Donkey Car Improvements

This week the team was working on making the Robo HAT control the throttle Electronic Speed Controller (ESC) and steering servo on a Donkey Car with only an RC Controller.

However, this is not just useful for Donkey Car. We have spoken with people working with NVIDIA Jetsons and found that they love the idea of being able to use a RC Controller to control their robots. It removes all the software issues that could result in accidents in heavier robots - where control is absolutely critical and drops outs are not tolerated. This is a great safety feature you can also install on your robots. Read on to find out more.

The current options for controlling a Donkey Car are very limiting.

This week we finished implementing the direct control of the car via a standard RC Controller that comes with the car body. It removes the pain points identified above.

How?

  1. Attach the RC receiver module to the Robo HAT MM1.
  2. Run CircuitPython code on the Robo HAT MM1 that:
  1. Run the Donkey Car software on the Raspberry Pi for capturing pictures.

Why?

There are a few reasons why this is a much better method than using the Bluetooth controller.

Results

A great few days for dramatically improving the Donkey Car Experience. You are able to check out the code on our donkeycar fork on GitHub here:

https://github.com/robotics-masters/donkeycar/tree/wallarug/rc_controller

Hidden Features - Reprogramming Pins

The Robo HAT MM1 has 8 pins labelled as SERVO and 4 pins labelled as RC_CH (Radio Channel). They are actually not completely locked to those functions. If your project needed 8 Analog Inputs and only 4 PWM Outputs - this is also achievable.

Everything related to the labels on the board are software enforced. It is very easy to use the pins with a different function, provided they support it. See the table below.

Pin NamePWM TimerAnalog Input
SERVO 1TCC0 [6]-
SERVO 2TCC0 [7]-
SERVO 3TCC0 [4]-
SERVO 4TCC0 [5]-
SERVO 5TCC0 [3]AIN[19]
SERVO 6TCC0 [2]AIN[18]
SERVO 7TCC0 [1]AIN[17]
SERVO 8TCC0 [0]AIN[16]
RC_CH 1TCC0[0]AIN[4]
RC_CH 2TCC0[1]AIN[5]
RC_CH 3TCC1[0]AIN[6]
RC_CH 4TCC1[1]AIN[7]

If you wanted 12 PWM outputs, it is manageable provided the board gets configured correctly. This gives users the flexibility to change to any desired need for a particular application.

Thank you for your support and we will be providing more updates soon!

Robotics Masters Team

Cian, Linda, Hans and Peter


Sign up to receive future updates for Robo HAT MM1.

Robo HAT MM1 is part of the Microchip Get Launched design competition!


Subscribe to the Crowd Supply newsletter, highlighting the latest creators and projects