Design, Analysis and Preliminary Validation of a 3-DOF Rotational Inertia Generator

This paper investigates the design of a three-degree-of-freedom rotational inertia generator using the gyroscopic effect to provide ungrounded torque feedback. It uses a rotating mass in order to influence the torques needed to move the device, creating a perceived inertia. The dynamic model and the control law of the device are derived, along with those of a comparable concept using three flywheels instead of a gyroscope. Both models are then validated through simulations. Further simulations are conducted to establish motor torque and velocity requirements, and the gyroscopic concept is identified as having the less demanding requirements. The mechatronic design of a prototype of an inertia generator is presented, along with modifications to the dynamic model. Preliminary experimental validations are conducted. As the prototype faces instability issues when using the flywheels at high velocities, they are conducted using 0 RPM initial velocities. The results confirm that it is possible to both reduce and increase the rendered inertia even with current limitations. Finally, improvements for a second version of the prototype are discussed.