It is important to pin-point the problem before sending in a repair team. Here is a circuit diagram. Programs are submitted to the remote lab and the results returned. Students have to submit programs to make the arm perform certain actions, such as press some buttons on a musical keyboard. Video and audio feedback are provided to allow the students to see the results of their programs.
Web interfaces allow access from any suitably equipped computer.
Disabled students can take part in a laboratory from their room. Subject to safety precautions, access to labs may be 24 hours. Expensive equipment can be shared between many universities. No university can afford to buy all the equipment it would like and this kind of technology opens up access to teaching equipment they could not otherwise afford. Sharing makes upgrades cheaper.