Some Dynamixel adapter boards

Technology
1

Hi,

Aside from the complex USB interface and Dynamixel Devices, I also designed at the same time some simple adapter boards to give more options when cabling Dynamixel-based robots.

Male to male adapter (I forgot the TTL version of the board when assembling the panel :frowning: ), for when you need a cable longer than what you have around and do not want to crimp your own.

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MX to XM adapter, to facilitate mixing the new XM/XH servos with the regular MX-R ones.

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3-port hub, for easier branching and when you do not need a 6 port hub.

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Power boards.
So here the idea is obvioulsy to give power to the servos (which is an annoying thing to do when using the USB2AX for example), but it has other more subtle uses.
The thing with the daisy-chained Dynamixel bus is that each connector has a resistance of around 10mOhm per contact (one for VCC, one for GND, and two per serov, so a total of 40mOhm per servo). This is not a lot, but when you put many connectors one after the other, it can have an effect, especially when using power-hungry servos. This can cause voltage drops along the line.
A potential use of these boards would be to create different power insertion points, in the robot to share the load - for example having secondary power insertion points ( or even just secondary ground reference points) around the end of the legs.

power_adapters.jpg1000×577 316 KB

Full album : https://goo.gl/photos/ShxQQ5JBH1xEhbJA7

6 Likes
2

Nice, you’ve been busy I see…:slight_smile:

For the simple ones male to male I usually solder straight female connectors pin to pin and then put some shrink warp around it. It’s actually quite robust and very small.

But the other ones are really useful.

3

Thanks :slight_smile:

Actually you have no idea, but I’ll talk about that later ^^

Yeah I used to do that too, nd have seen it a few times in the wild too, but that’s basically the idea: making it more easily accessible to people who are not comfortable ordering the righ Molex connector and soldering it.