Arm and Hand Development
by paloskar on Jan.19, 2011, under Arms, Servos
One of my long time favorite topics in robotics is visual servoing. In order to be able to do this, my robot needed fairly sophisticated arms and hands. Each of the old hands had 2 degrees of freedom: one in the shoulder and another in the elbow. The new construction sports 5 DOFs: two in the shoulder and one in the elbow, wrist and hand.
The upper three servos are regular sized Hitec HS-475HB, while the lower two (wrist and hand) are micro sized Hitec HS-85BB. The frame of the arm is built of Lynxmotion Servo Erector Set elements, just like the legs. The hand is a gripper device produced by Robix and sold by Lynxmotion.
After the construction was completed, I wanted to test the hand’s precision. I connected the arm servos to the Roboard unit and sent a series of pre-programmed movements to grab a small red ball.
This worked out quite well as you can see it in the above video, which encouraged me to continue with my visual servoing ambitions.
