View Full Version : Why are Robotic Arms so Gigantic and Heavy?

01-28-2012, 09:58 PM
So, I'm looking to build an arm for an industrial application. But, every industrial arm I see is gigantic and looks very heavy. I'm wondering if I'm totally missing something because some of the applications are for lifting 0.05kg or less. Like this one: http://www.youtube.com/watch?v=RCBQqEGp8Go
So why the hell do they use such a massive arm?
Maybe many robot builder prefer this. But, would it be bad if I made it lighter? Are the motors less durable or something? For example, I'm considering to use Dynamixel servos. Is that a bad choice? I'm thinking maybe they use such big arms because they can handle the constant usage and dissipate heat better? I don't want to get too far in my design only to realize there is some fatal flaw because I used smaller servos and light weight parts. Any help would be much appreciated!



01-28-2012, 10:43 PM
Big and solid means nice and precise... otherwise you can easily have a very jiggly arm, with the lengths commonly seen in industrial applications (Ok, I have car-making arms in mind).

If you don't need extreme precision, a minimal arm is fine, but otherwise you'll probably have problems.

Edit: Then I watched your youtube video. It's pretty funny, because that seems like a dumb engineering choice to me. A pick n place mechanism could probably do similar and be much much faster.