US Patent 11168768 Collaborative shear display

A haptic device includes a network of motorized shear actuators. The shear actuators each include a drive mechanism and a lead screw having a threaded outer surface rotatably coupled to the drive mechanism and extending along a primary axis. A carriage is movably coupled to the lead screw by a nut having a threaded inner surface and is disposed within a chassis. One or more flexure springs are attached to the chassis and are configured to exert a reactive force to resist a force applied to the carriage in a direction orthogonal to or substantially orthogonal to the primary axis. The flexure springs may cooperate with a stop mechanism to improve the mechanical robustness of the shear actuators under applied loads.