Robotics

Case Study:

Overview

Robonaut 2 is a dexterous humanoid robot that was designed to operate either autonomously and side-by-side with humans alike. Being able to operate in both environments is critical, as this can allow for humans to work more efficiently in some situations while eliminating them from others which may be deemed too dangerous. Such a scenario is not limited to outer space, as countless examples can be found in everyday life in fields such as machine maintenance and mining. With this in mind, Robonaut 2 was developed not only to coexist with astronauts on the International Space Station, but to act as a prototype of robots to come.

Challenges

Two major challenges faced engineers when developing Robonaut 2.

Develop a robot that is aware of its environment, including other humans
- This required monitoring not only position, but also torque
  - Consider a motion as simple as shaking someone’s hand
- Develop a robot that is appropriate to be used in space. This includes, but is not limited to:
  - Low mass
  - High resistance to shock and vibration
  - Compact size
  - Materials capable of being outgassed to work in low pressure/vacuum

Resistance to magnetic interference

Solution:

Engineers choose Netzer Precision’s DS absolute position Electric Encoder to address these challenges. The DS encoder offered the high accuracy needed for positioning and by using two encoders, torque was also able to be monitored. Furthermore, Netzer used special components and housing materials to meet the outgassing requirements. The capacitive technology of the DS encoder is fundamentally light weight, offers excellent resistance to the shock and vibration of a rocket launch and has a low profile. Last, capacitive sensors are not susceptible to magnetic interference which can result from being in close proximity to frameless motor magnets.

Results:

Robonaut 2 flew to the International Space Station on the space shuttle Discovery, mission STS-133. It was the first US-built robot on the ISS as well as the first dexterous humanoid in space.