Running 9 BLDCs for 3 legged robot

Hello, I want to make a 3 legged robot for my Mechatronics final year project. This would require me to get 5 Odrives. My issue is what battery configuration should I run as electronics isn’t my strong suit. Should I get a battery for each Odrive? Can I get fewer batteries and use a potential divider circuit? Suggestions would be appreciated. Thank you

Well that’s funny, because that is what I have built.

For any legged system you should try to calculate what the maximum power draw will be. That will tell you what the requisits are for your power delivery system. Which actions will the robot perform that require maximum effort?

Generally speaking, a single battery should be able to supply more than sufficient power. How long the battery lasts, will depend on how efficient you can get the movements and which movements you require.

Also, this sounds like an ambitious project. You may want to look for ways to simplify your robot, or establish a minimum viable product first. This wil help you validate your expertise and might even be enough to get you an outstanding score for you final year project.

Finally, this post describes how I have setup my power delivery. It’s works for me, but is far from the only solution.

BTW, I don’t know what a ‘potential divider circuit’ is doing here. :stuck_out_tongue:
A ‘potential divider’ composed of resistors CANNOT be used to supply power to anything. It only steps down voltage for something that draws zero current, like a voltage sensor or ADC. :wink:

I’d recommend using the 56V ODrive, whatever your supply voltage is going to be. They are more robust, and more than twice as powerful as the 24v ODrives.
The higher your supply voltage, the higher the maximum speed, and the higher the maximum rate-of-change of Torque.

Do you know approximately how much torque in Nm that you need for each motor? Have you already selected your motors?

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