Description
Stepper motors are ubiquitous in hobby robotics projects: If you make a robotics or automation project today, it is very likely you will use them. Almost all DIY projects from 3D printers and CNC mills, to air hockey and juggling robots use them. However in industrial automation, brushless servomotors have taken over, and it’s clear why: They don’t lose steps, are much more powerful, efficient, and silent.
However, brushless motors are not unique to expensive industrial automation equipment. In fact, you can get some very powerful and cheap motors at hobby shops. The electronics to drive these motors are also dirt cheap. So how come virtually no non-industrial automation systems use them?
To be honest, I have no idea. Seriously, a driver that allows this should clearly exist.
But since it didn’t, I decided to make one.
And you are invited!
This project is open source, both in hardware and software, and I warmly welcome anyone who wants to join.
Details
Boards are available
ODrive v3.3 boards are available at the ODrive Shop.
Key specs:
- 2 motor channels, designed for >100A peak current.
- 1 DC-DC converter channel
- For powering the system with an arbitrary voltage power supply, or
- Use of a brake resistor
- 24V bus voltage
- USB, CAN, UART, PWM, and step/dir interface (read more below)
- Encoder feedback for arbitrarily precise movements
- Supports power regeneration
- Use of a high power density Li-Po battery means you can achieve >1kW peak power output with only a modest power supply.
- It will feature various optimal control strategies and motion profiles.
- Permissive licence on both hardware and software: You use this project in anything you like, even commercial products (as long as you attribute this project’s contributors).
Demos
The design is based on two earlier prototypes.
Here are some very simple demos with v2. The peak power output in these tests were only about 60W. The new version (v3) will be able to deliver much more power.
Read more: ODrive – High performance motor control
