We set out to create a motor control scheme to address the dynamic needs and demands of the research robots that are developed and used by the Personal Robots group at the Media Lab and other robotics developers around the globe. After years of iteration and experience, the result is the MCBMini v5, a full-featured, scalable, and open source motor control solution.

The MCBMini v5 is a single circuit board that provides two closed-loop motor control channels (which could be combined to control one larger motor) with analog or quadrature feedback options, five analog pins for switch/analog input, and both TTL level serial and USB communication interfaces. The boards can be connected together to share a single communications bus to control many motors independently in a streamlined fashion.

The Next Generation of Motor Control

MCBMini v5 is the next generation of the original MCBMini project. Improvements include:

• The original MCBMini required a separate communications board in addition to the motor control boards themselves. Every MCBMini v5 board has built-in communication capabilities, so no other boards are needed.
• The previous design had a significantly limited quadrature encoder tick frequency.
• The v5 uses an ARM microcontroller (STM32F3) with a much faster clock frequency, more memory, and more peripheral capabilities than the previous design's microprocessor (ATMega168).
• The v5 has more programmable extra pins (five instead of two).
• The v5 has on-board flyback diodes which improve control performance.

The videos below are demonstrations of how the original MCBMini boards can be used. The MCBMini v5 boards are enhanced versions of the boards shown in these videos. ~~~
vimeo:
id: 76356553

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id: 76356528

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Licenses

This project contains three different kinds of licenses:

• MCBMiniServer (the Java host software): LGPLv2
• Printed circuit board designs: CC with Attribution
• Motor control firmware: GPLv2

Manufacturing Plan

All assembly will be performed by a professional fabrication company we’ve been closely working with. The printed circuit boards have already been tested and verified to work.

Risks and Challenges

Because this is a revision of a well-tested board, there is always some chance of some bugs creeping in. It should also be noted that this board is an open source development project so its design and firmware is an ongoing project. We have tested the hardware of the boards and feel comfortable with their performance and as we gain experience with the firmware we will release bug fixes as we come across them. New firmware can be conveniently flashed to the boards via USB.