FWR is developing a fully electric robotic arm with electronics, sensors, and electric motors housed in an external Actuation Box: the motors’ motion is transferred to the arm joints via efficient, large-bandwidth, flexible Fluid Wire transmissions, combining the controllability of electric motors and the high specific power of fluidic transmissions. Thereby, (i) the arm is simple, passive (no electronics, sensors, and motors on board) lightweight and basically free of any components, while (ii) the Actuation Box offers simple-yeteffective cooling, shielding and sealing possibilities (protecting the critical components from environmental factors, e.g., radiations, water, temperature, flammable gasses and dust including regolith), that would not be possible relying on traditional design approaches or using different types of transmission systems.
Overall, FWR’s robotic systems are intrinsically capable of operating in ANY harsh environment. Moreover, the extreme transparency of Fluid Wires (low-friction, high-bandwidth) allows the electric motors to also act as torque sensors, preventing the use of expensive and fragile force/torque sensors, thereby enabling very accurate, and reliable sensorless force-control in any circumstance.
The peculiarity of our space robotic arms consists in the possibility of locating the Actuation Box inside the spacecraft or satellite body: besides offering superior protection for motors, sensors and electronics against cosmic rays and thermal excursions, a range of unique competitive advantages are generated:
- the electric motors of our robotic arm can be connected to the spacecraft’s cold plates to achieve enhanced thermal dissipation and, thus, remedying to the severe overheating issues experienced by the actuators of any other space robot due to the lack of convection in vacuum: this results in dramatic performance improvements and/or mass reduction (actuators can be undersized).
- equipping spacecrafts and satellites with FWR lightweight arms enhances energy efficiency and controllability, as smaller inertial disturbances are produced by the arm motion and less compensation by thrusters is required.
- specific space customizations may include using one single actuation box to selectively control different robotic arms, achieving dramatic mass reduction and cost savings.
- perfect sealing, very low outgassing and advanced thermal management of our architecture prevent contamination and influence on surrounding precision space instrumentation.
