One of the central features in KITE’s Challenging Environment Assessment Laboratory (CEAL) is a large six degree of freedom motion system. The six “legs” of the motion base are independently controlled hydraulic actuators. This provides the ability to move the upper flying frame of the simulator through any combinations of the three translational degrees of freedom (surge, sway and heave) and the three rotational degrees of freedom (roll, pitch and yaw).
This type of motion system is commonly used in airline flight simulators. Our simulator differs from typical uses in its extraordinary flexibility of applications involving human interactions with different environments. Our simulator’s flying frame can host four interchangeable laboratory pods that are hoisted onto the motion base using a large crane: DriverLab, StairLab, StreetLab and WinterLab. The laboratory pods are diverse, from a car to a streetscape to staircase to a wintery ice chamber.
The motion capability enables the simulation of realistic and challenging conditions in the labs. For example, if a bathroom is mounted, balance can be disturbed with a sudden shake as an occupant shifts their weight to transfer into a bathtub. Vehicle motion cueing is synchronized with the visual scene to provide the perception of driving. An icy floor can be slowly inclined up to challenge winter boots or tires on mobility devices with complex cross slopes. Each laboratory can be configured in different ways to meet an experiment’s needs.
The motion system is the Bosch Rexroth HyMotion-11000-6DOF. The flying frame can accommodate a lab with a footprint of 6.0 x 5.6m. The system is powered by a 170kW hydraulic power unit, 228hP. Maximum payload above the actuators is 11,900kg. Dedicated computers provide real-time control of the motion and the system includes experimental equipment, such as force plates and motion capture for a robust measurement system. Integrated safety interlocks, watchdogs, overhead harness systems are a few of the safety features in the simulator.
Each actuator has a maximum stroke of 1.524m. From a neutral position, the motion platform can move: Surge +1.174 m, -0.892 m, Sway ±0.926 m, Heave +0.876 m, -0.761 m, Roll ±23.15˚, Pitch +22.00˚, -22.70˚, Yaw ±26.80˚. The simulator moves with a maximum linear velocity of 1.5 m/s and 40˚/s angular, and maximum linear acceleration of 8 m/m/s² and 100˚/ m/s² angular.
The motion base is a large six degree of freedom simulator with four interchangeable labs. Adding motion capability to these diverse labs enables the simulation of realistic, but extremely challenging environmental conditions.