Robotic arm
Theory
- http://www.societyofrobots.com/robot_arm_tutorial.shtml
- http://www.scholarpedia.org/article/Light-weight_robots
- http://www.xrobots.co.uk/
connector
Rotating Electrical Connector
- http://www.swivelelectricalconnector.com/rotating_electrical_connectors/swivel_electrical_connector_best.php
- http://aksr.co.kr/tech/images/faq04.jpg