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Nunno
12-18-2009, 04:22 AM
I would like to build a plus sized aluminum gripper. What would be your recommendation for the "best" all around gripper designs?

Key points:

Strength/precision
Low total motor/servo count (preff one)
ease of locating an object within the gripper (equal closing)
Broad object workability (pens and cans to lifting a bag)

Thinking maybe something along the lines of the gripper on the OWI Arms?

DresnerRobotics
12-18-2009, 12:19 PM
What type of servos did you have in mind for use?

Nunno
12-18-2009, 01:33 PM
Not really sure. Figured I would decide after narrowing down the design being that its leverage etc would effect the motor strength needed. I know im open to just about anything. servo(within reason), dc motor servo conversion or maybe a linear actuator if i can find something small/strong enough. I would like to keep total motor/controller budget to around $50-$100 with the ability to lift upwards of 10lbs.

I really like a central three prong for ease of construction but I dont see it being very effective for grasping cylinders from the side.

MikeG
12-18-2009, 02:05 PM
Gripper grip not lift, right? Do mean grip force of 10lbs or gripper and arm that can lift 10lbs?

Nunno
12-18-2009, 02:14 PM
Im sorry, I would like the gripper itself to be able to hold an object around 10lbs.

MikeG
12-18-2009, 02:30 PM
You don't need a gripper to "hold" an object a scoop can handle that. Gripper are not defined by holding force but by gripping force. Do you mean 10lbs of gripping force?

Edit: motors might have a holding force spec but that is really related to stall torque.

gdubb2
12-18-2009, 02:54 PM
For that much force, a small pneumatic cylinder might be worth considering. They can be operated with Co2, air, or whatever.

Gary

MikeG
12-18-2009, 03:06 PM
As for gripper designs, look in your toolbox. Pliers, channel locks, scissors...

darkback2
12-18-2009, 04:01 PM
similar to gdubbs idea how about linear servos?

One thing to consider is that if you are trying to hold a number of different things then your gripper will not be perfect at any of them. for example if you want to be able to hold something that weighs 10 pounds, well...the density and shape of the thing will greatly change your gripper design, and therefor the capabilities of your gripper.

YouTube- NASA ATHLETE jump to 2:00 or so.