Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: jidhinjames on October 26, 2012, 03:01:20 PM

Title: touch sensitive finger gripper
Post by: jidhinjames on October 26, 2012, 03:01:20 PM: Hi all

Its my first time posting in this forum. Im a beginner in robotics and attempting to built my first robotic arm

I kinda saw an article other day where a finger gripper gripping and lifting and egg without cracking or breaking it.

I was wondering if someone could give me an insight on the technology used in this type of grippers.What kind of actuator and force calculation methods are being used. It looked like the fingers grip with the necessary force, sensing the geometry of the object to be picked by the finger tips. Do any kind of touch screen technology is associated with this gripper?

I would appreciate any kind of help you guys can provide me with..be it an article or a thread in this forum or a pdf or any website..any info would be of help.

Thank you
Title: Re: touch sensitive finger gripper
Post by: newInRobotics on October 26, 2012, 06:55:47 PM: It's most likely as simple as pressure sensor. If You know what force can crush shell of an egg, then using pressure sensor You can make sure that limit is never reached.
Title: Re: touch sensitive finger gripper
Post by: lrmall01 on October 27, 2012, 03:34:10 PM: Here is an article I saw that might be similar to what you are talking about.

http://www.engadget.com/2012/08/04/takktile-turns-digital-barometers-into-open-source-robot-touch-s/ (http://www.engadget.com/2012/08/04/takktile-turns-digital-barometers-into-open-source-robot-touch-s/)

They are basically using an off the shelf digital barometer with a little pressure chamber that is used for force feedback. These are open source hardware so you can try to make your own if you like.
Title: Re: touch sensitive finger gripper
Post by: Soeren on October 29, 2012, 04:44:42 PM: Hi,

Quote from: lrmall01 on October 27, 2012, 03:34:10 PM
Here is an article I saw [...]
I beg to differ ;)
Title: Re: touch sensitive finger gripper
Post by: Soeren on October 29, 2012, 04:56:48 PM: Hi,

Quote from: jidhinjames on October 26, 2012, 03:01:20 PM
I kinda saw an article other day where a finger gripper gripping and lifting and egg without cracking or breaking it.
Post a link, if you want people to know what you're referring to.

Quote from: jidhinjames on October 26, 2012, 03:01:20 PM
I was wondering if someone could give me an insight on the technology used in this type of grippers.
Without a link, we can only guess!

There's several methods for controlling the amount of power to below the egg-breaking-point; force feedback via one of a number of sensors (cheap homemade or store bought expensive), "torque" control of the actuator with a preset maximum, sensors that detect when an object is slipping (to increase pressure to the point where it's not) etc.
But, if this is your first mechatronics project, I'd recommend a little less ambition - build something simpler and learn while you go.
Title: Re: touch sensitive finger gripper
Post by: lrmall01 on October 30, 2012, 06:03:31 AM: Quote
I beg to differ

Thanks for pointing that out - I updated original post with the proper link.
Title: Re: touch sensitive finger gripper
Post by: jidhinjames on October 30, 2012, 01:52:56 PM: Thank you guys for all your response.
Maybe its a little too over ambitious.
But i see this as a learning curve. Even if i dont succeed I do know what are the flaws and where i need to focus more on.

I still appreciate all kind of help you guys can provide me with.

Thanks a lot again for all ur help