Accuracy and Repeatibility of Smart Servos

Help & Support Robot Parts
1

Hello,
I recently purchased a couple Dynamixel AX-12A Smart Servos for a project I am working on. I love the size and ease of control, but am having issues with accuracy and repeatability. I have a payload of less than 100 grams and find that I cannot repeat a movement within a third of a degree.

Am I just expecting too much from a very inexpensive motor?
Would I be better off with the HerkuleX DRS-0201?
Would a stepper motor give me better precision and repeatability, if speed is really not an issue?

BTW, I just started tinkering with robotics, and am not an engineer. Any and all advice you can give me will be greatly appreciated!
Illinijeff

2

That’s odd, the Dynamixel AX-12A should have a precision of 0.29 degrees (300 degrees divided by 1024 steps). How much error are you observing?

The HerkuleX DRS-0201 has a similar precision of 0.325 degrees (approx 320 degrees divided by 1024 steps). We would expect it to behave similarly, but it could be different depending on what you are observing with the Dynamixel.

Stepper motors would be more precise, especially if the load is only 100g. The following motors have precisions of 0.325 degrees and even smaller. Note however that their max speed is much slower.

Hope this helps,