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jyotirmoy
04-23-2008, 02:57 PM
hi friends,
am new to the forum...
i was thinking of initiating a project on robotic arm using an accelerometer chip(may be adxl330)
i am in a doubt if i can make a 4 degree of freedom arm using just one accelerometer chip...
anybody has got any idea????:confused:

Adrenalynn
04-23-2008, 03:40 PM
Hi Jyo',

What you'll need to look into is Kinematics - and specifically, inverse kinematics.

I'm just one long weekend away from attempting to prove exactly that concept. I want to see if two three axis accelerometers and inverse kinematics can provide for a 6DOF arm's reliable control. I have an arm built (CrustCrawler SG6 from Trossen Robotics here), I have a servo controller (SSC-32, also purchased here), and a bunch of software written. For rapid prototyping, I'll be starting-out with the WiiMote and its 3 axis accelerometer.

If you make any progress in the meantime, please keep us posted!

Alex
04-23-2008, 03:48 PM
What about using something like this behemoth:

http://www.sparkfun.com/commerce/product_info.php?products_id=8454

:D:D

LinuxGuy
04-23-2008, 04:04 PM
What about using something like this behemoth:

http://www.sparkfun.com/commerce/product_info.php?products_id=845 (http://www.sparkfun.com/commerce/product_info.php?products_id=8454)
I soooooooooooooooooooooo want one of these as soon as I can find a good use for it.

8-Dale

Adrenalynn
04-23-2008, 04:04 PM
Ouch. I'll keep my $30 in Wiimotes, thanks. :P

LinuxGuy
04-23-2008, 04:07 PM
Ouch. I'll keep my $30 in Wiimotes, thanks. :P
I have an ADXL330 3 axis accelerometer module from Spark Fun, but not enough ADCs to interface it to Hammer. :sad: This is where I hope a Phidgets Interface 8/8/8 kit (with the blue LCD) will come in once I have th Phidgets libraries ported into buildroot and can cross compile them.

8-Dale

Adrenalynn
04-23-2008, 04:09 PM
I have my ADXL330 talking to a Windows PC right now - but the Wiimotes are so purdy. :)

Alex
04-23-2008, 04:14 PM
Ouch. I'll keep my $30 in Wiimotes, thanks. :P

ah come on adrenalynn, you can't tell me that massive IMU 6DOF doesn't get you all warm and fuzzy feelin inside:D

LinuxGuy
04-23-2008, 04:15 PM
I have my ADXL330 talking to a Windows PC right now - but the Wiimotes are so purdy. :)
I want a Wiimote also. I can't decide what I want to get myself for my birthday. Have you seen what Johnny Lee can do with Wiimoties?

8-Dale

Adrenalynn
04-23-2008, 04:26 PM
Yuppers! And soon yall will see what I can do with Wiimotes. ;)

Adrenalynn
04-23-2008, 04:27 PM
ah come on adrenalynn, you can't tell me that massive IMU 6DOF doesn't get you all warm and fuzzy feelin inside:D

I don't think I can comment on that - it's a family-friendly forum, I believe. :p

jyotirmoy
04-24-2008, 11:36 AM
guys... i guess I made a fundamental mistake while framing my question. i have a situation ... i want to emulate my hands gesture on a robotic arm. can i use one accelerometer chip(adxl330) and take the movements of 5 fingers(without any joints) and run 5 separate servo motors.
i hope , am clear this tym

Adrenalynn
04-24-2008, 11:56 AM
No. See your other thread - and it's easier if you don't make multiple threads for the same question.

Thanks!

Alex
04-25-2008, 10:43 AM
Other thread closed. For this discussion, please reply to this thread.

GWJax
04-25-2008, 03:19 PM
If you do find a way to just use one accelerometer without changing the chip to each finger to program the sequence and then replaying it back as a prerecorded action then please let us know how you did it. Else you will need multi chips for this or as I have already told you to use the flex resistor sensor for the fingers and the accelerometer for the wrist actions.