I was actually wanting a DC servo but it is kind of looking like there impossible to get and even if I did manage to find one they would be ridiculously expensive. Any suggestions of some thing that would do a similar job to a servo.
I am building a robot arm I have found that hobby servos just aren't powerful enough to lift more than about a 100 grams and I want it to lift more than that. I can get a servo with a torque of 24 kg cm which is pretty good but I was hoping to get even more than that. A stepper motor might work quite well if I can get one with high torque speed is not an issue it doesn't matter how slow it is. I am also considering pneumatic pistons although I am not sure how hard they are to get or how difficult they are to work with.
Steppers will be a much better option for what you are after. The torque characteristics are perfect for slower speeds that you tend to find in hobby robotics, and you will not need to gear them down like you will with a DC servo.
Precise positioning is easy with fewer electronics that a servo motor with encoder.
Plenty of stepper motors and driver boards on TradeMe
Pneumatics are useless for positioning since they will just travel to the limit of their travel at a speed based on the pressure you put into them. hydralics would be a better option if you need control of position rather than just force.
Is the physical size of the motor important? If space is not a problem the use the motor out of a fisher and paykel smart drive washer. They are a brushless DC motor. And come with rotor postion sensors already fitted.
Aredwood: Is the physical size of the motor important? If space is not a problem the use the motor out of a fisher and paykel smart drive washer. They are a brushless DC motor. And come with rotor postion sensors already fitted.
I think that would be over kill I don't know how much power they use but probably quite a bit I would have to run the robot off the mains.
If you only need the motor to operate at slow speeds then it will work on 12V. And maybe as low as 5V. You will only need mains if you want it to operate at 1000rpm or so. (the fast spin speed).
Are you subscribed to our RSS feed? You can download the latest headlines and summaries from our stories directly
to your computer or smartphone by using a feed reader.
Trusted
