In this video I explain how the servo motor rotational energy can be transferred linearly to the joint where it actuates the joint back into rotational motion. This is achieved through a pulley system with strings. The motor acts like a fishing reel, reeling in the muscle string and this string passes through teflon tubing (just like bike brakes wire passes through rubber hose) until it reaches the desired bone joint tie in point where the string pulls when reeled in by the motor and this pulling acts as muscles flexing in principle and causes the body's joints to move realistically! The advantage this brings is the ability to locate any number of motors in any location throughout the robot and transfer the energy they create to any joint anywhere on the robot. By enabling us to transfer energy in this way, fine control and great power can be generated for every joint without the need to find super tiny servo motors that have to be physically located adjacent to the joint it actuates. My study of the way bike brakes work was the inspiration for this joint actuation design. It is the same theory. Actually, winches on cranes and the fronts of jeeps act also by a similar principle. Also, you will note that the fingers have tons of joints and the wrist is packed with little bones. I will need over 20 motors to handle the many complexities of the hand. These motors will be mounted throughout the forearm of the robot arm. Also, I realized during my study of the arm that our wrists don't actually twist in order to rotate our hand, but rather our forearm bones rotate which rotates the hand. I actually thought just a single bone would be fine for the forearm until I discovered how important the second bone in the forearm is for hand rotation purposes. From now on I'm not going to question God's designs! I'm going to try to stay as close to them as possible.
