Haptic actuator using magnetorheological fluid clutch apparatus

A haptic magnetorheological (MR) fluid actuator unit comprising:

• at least one torque source;
• a structure;
• at least a pair of magnetorheological fluid clutch apparatuses, each of the magnetorheological fluid clutch apparatuses having:
• an input assembly including
• an input member rotatably mounted to the structure to rotate relative to the structure, and
• at least one input shear surface rotating with the input member;
• an output assembly including
• an output member rotatably mounted to the structure to rotate relative to the structure, and
• at least one output shear surface rotating with the output member, the at least one output shear surface opposite the at least one input shear surface;
• at least one annular space separating the shear surfaces;
• magnetorheological (MR) fluid in an MR fluid chamber including the at least one annular space, the MR fluid configured to transmit a variable amount of torque between the input assembly and the output assembly when subjected to a magnetic field;
• and
• at least one coil actuatable to deliver a magnetic field through the MR fluid in the annular space, the magnetic field controllable to transmit a variable amount of torque from the input assembly to the output assembly;
• wherein the output member of the pair of magnetorheological fluid clutch apparatuses being a common output member;
• wherein a totality of seal(s) and bearing(s) contacting the output assembly are between the output assembly and the structure.