ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange
Ask Your Question

Cheaper motors than Dynamixels?

asked 2013-11-26 08:53:22 -0500

llSourcell gravatar image

I've built a 7 DOF robotic arm using dynamixels, and the total cost of the motors was about 2000. I think this is way too expensive, I mean we can't commercialize robotics if the motors are so expensive. I think that making the motors cheaper is the key to getting affordable robots out there. The problem is, hobby servos won't do, we need the feedback of robot motors for effective computation of robotic algorithms.

Dynamixels are great, don't get me wrong, but does anyone know of any robot motors that are cheaper?

edit retag flag offensive close merge delete

3 Answers

Sort by ยป oldest newest most voted

answered 2013-11-26 14:59:19 -0500

fergs gravatar image

updated 2013-11-26 15:00:31 -0500

You generally get what you pay for. With Dynamixels, you are making a trade-off of getting a fully functional and tested actuator out of the box, versus spending a lot of time rigging up your own actuators, and probably dealing with numerous engineering efforts. If you are making a million robot arms, it probably makes sense to spend significant engineering effort to design custom actuators. If you are making only one, why not leverage the engineering effort that Robotis has already put into Dynamixels.

If you open up a Dynamixel and take a look at what is inside, you'll quickly realize the prices are not crazy. There's a high end motor, numerous custom gears, a custom case, custom driver board -- furthermore, someone built this product, and then a retailer handled import/storage/etc so that you could go out and have it delivered via Next Day UPS if you so choose. And if something goes wrong with that servo, you have a company to call up and get a replacement from.

The best hope of cost reducing these components is huge volume. Figure out a killer app, and order parts for a million 7-dof arms, and you will almost certainly get a nice quantity discount. Of course, you probably wanted to make a profit on selling that 7-dof arm with your software, right? Or at least, keep yourself employed? Well, then your arm is still probably going to retail for more than $2k.

Also, I'm not sure how we commercialized cars, but they cost more than $2k. Maybe the robot just needs to generate more value...

edit flag offensive delete link more


Thanks for the response Mike. Definitely some stuff to think I have to think about. Btw, UBR-1 rules! Keep up the good work. I'm moving to the Bay Area on Jan 6th, hopefully I'll see you around somewhere at a robotics meetup or something. Cheers.

llSourcell gravatar image llSourcell  ( 2013-11-26 15:05:26 -0500 )edit

To add on the "get what you pay for": Manipulators aren't cheap, especially when used in robotics requiring some precision and feedback. We do need the quality! I actually believe 2000 to be REALLY cheap for a 7-dof manipulator. Depending on the use-case you pay magnitudes more for something usable.

dornhege gravatar image dornhege  ( 2013-11-27 05:52:24 -0500 )edit

answered 2013-12-10 23:44:25 -0500

Paul Jurczak gravatar image

updated 2013-12-12 15:34:41 -0500

There is some nascent competition to Dynamixel with slightly lower prices, but much narrower product line. The best quality product is probably HerculeX by Dongbu Robot. Other options are somewhat sketchy: Spring Model and Uptech.

RoboBuilder claims to be the first one in this business and has a new generation of their servos (SAM-160E, SAM-210E).

The forum doesn't let me publish links in this answer - need more karma :-(

edit flag offensive delete link more

answered 2013-12-12 02:47:39 -0500

David Galdeano gravatar image

I think an option is to use the openservo modification: You will have more control and digital feedback but the mecanical quality is the same of low end servos.

edit flag offensive delete link more

Question Tools

1 follower


Asked: 2013-11-26 08:53:22 -0500

Seen: 4,118 times

Last updated: Dec 12 '13