Hardware-in-the-Loop Simulation of Modular Antenna Assembly

Robots are playing an increasing role in space exploration and in-space servicing. Robotic arms are
good for performing in-space tasks such as modular assembly. The SPIDER arm (SPace Infrastructure
Dexterous Robot) of the OSAM-1 mission represents an example of a system that can perform modular
antenna assembly tasks in environmental conditions that would be dangerous for astronauts. One of
the WVRTC activities is to perform independent verification and validation of the SPIDER assembly
operations.

Space robotic systems adopting large manipulators such as the SPIDER arm are complex to test
and verify under normal 1-G conditions. Our work involves proof-of-principle testing of a hardware-inthe-loop (HIL) simulator operating in 1-g conditions, which replicates the motion of the space robot
end-effector under the same geometric, kinematic and dynamic conditions, and in response to externally
applied forces from its space environment.

In particular, our software simulates in real-time the robot dynamics inclusive of flexibility, an
important aspect in case of a long robotic arms operating in 0-G conditions. For example, the same
oscillatory motions of the space manipulator’s end-effector can be mimicked on ground through our
industrial manipulator, allowing us to test the feasibility of complex operation such as assembling
modular components.