Outer

Hey guys, great forum you have going here especially seeing how active it is. Quick intro? Totally new to robotics but Im gonna try my hand at building a robotic arm. Decided to start the project on these forums, will be interesting to see how it goes!

Hi, I've always been interested in humanoid robotics ever since seeing Ghost in the Shell wayyy back in the 90's and have decided to build a simple anthropomorphic robot arm that simulates the movement and speed of a human arm. Im also planning to make the arm react to its environment, but only once the arm itself is constructed and control software is written. This of course will just be a hobby, mainly to break into robotics and see where it takes me. If successful, I would like to construct a full size but limited humanoid robot. I've no plans to make this future bot capable of any type of self-supported locomotion like walking or running. At the most it would be great if it could balance itself enough to sit on the couch having a beer with you without falling over Anyways I'll leave that for the future, for now Ill just want to construct this simple yet fluid arm. Plan to use 2 control boards, one to control the voltage to the arm, the other to control the arms movements. Eventually the second board will be plugged into my pc where I can fine tune/calibrate the arms movements. All in all, the system will look something similar to this. AS for points of movement, there will be the shoulder, elbow, wrist, hand and fingers. This stuff seems pretty well covered on theinterwebs so Ill shoot on over to the stuff I need help with, the actuators and arm construction itself. From the research Ive done, I see three options for the arms actuation. Pneumatic artificial muscles, Dieletric Electroactive polymer artificial muscle and Ionic Electroactive polymer artificial muscle. You can find more info on these three on Wikipedia/Google, some pretty good info to. Of course there's also your standard electrical motors and servos, but Ill just be using those just for the fingers. The Dieletric Electroactive polymer artificial muscle is apparently perfect for what I need when it comes to the rest of the arm. So next would be the choice and acquisition of materials, then a bit of experimentation. As I'm totally new to all this the only DEA I can think of thats easily purchasable is an acrylic elastomer film called VHB 4910 produced by 3M. The website environmental-robots.com also sells DEA/EAP products, but there way out of my price range How would you guys recommend I configure the elastomer film to behave like the human muscles? One Idea I had taken from the wikipedia article, was to roll the film around compression springs but have each muscle made up of about 5 individually wrapped compression springs which would vary depending on the size of the muscle. Stuff I cant find much info on is how many muscles I'll need, should I replicate every muscle in the arm or only a select few? What kind of materials should I use for the skeleton and joints? This is where I start to struggle with a lack of robotics/anthropology experience so any input would be greatly appreciated.