New Servos

Published on 2023-06-14 in Wee Bug.

I like the tiny robot very much, but I didn’t publish the design files for it, because the Hobby King servos I used for it are discontinued and you can’t buy them anymore. But then I went to Aliexpress and searched for 2g sub-micro servos, and lo and behold, there is a whole bunch of them out there. They don’t have a model number – all they tell you is that they have POM gears and 260° range of motion. And one of three kinds of plugs to choose from. They are slightly more expensive than your regular 9g servos, at about $2, but still very cheap. So I decided to go ahead and try to make another WeeBug with them.

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Oh, right, and they are black instead of white. So I got purple leg pieces this time around. I also used a slightly different battery holder, but it didn’t require any modifications.

Now how do the new servos work?

Wow, they are fast! Much faster than the white ones. During calibration I had the robot literally jumping on the table when the legs adjusted their positions. I think I will be able to make this one scuttle around much faster than the white one.

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Other than the speed, I don’t really see much difference. They have enough torque, and I’m only using the standard 180° range of motion anyways. There is no noticeable jitter or other problems.\

One difference is that those servos don’t come with mounting screws, so you will need some screws of your own to attach the servos to the leg pieces. I also made the holes in the leg pieces too small, so some rimming/dremelling was necessary to make the servo horns and the screws fit correctly.

I will be fixing those mistakes, and then I will publish the design files.