Abstract: A method of monitoring movement of a robotic arm, the robotic arm being arranged to be moved by an actuator, the method comprising: determining an expected robotic arm condition based on a known robotic condition and a torque applied to the robotic arm by the actuator; measuring an actual robotic arm condition during movement of the arm caused by the applied torque; and determining whether a collision has occurred by comparing the actual robotic arm condition with the expected robotic arm condition and generating a collision signal if a difference between the actual robotic arm condition and the expected robotic arm condition exceeds a threshold.

Abstract: An actuator comprising: a motor comprising a housing and a drive shaft, the motor arranged to rotate the drive shaft relative to the housing about a drive shaft axis; a first torque transfer device comprising a first drive member on the drive shaft and a first driven member on a second shaft, the first drive member being arranged to transfer torque to the first driven member, such that the first torque transfer device is arranged to transfer torque from the drive shaft to the second shaft, the second shaft being rotatable about a second shaft axis spaced from the drive shaft axis; and an output torque transfer device comprising an output drive member on the second shaft and an output driven member, the output drive member being arranged to transfer torque to the output driven member, such that the output driven member rotates about an output axis; wherein a torque ratio of the output torque transfer device is smaller than or equal to a torque ratio of the first torque transfer device.

Abstract: A pulley system comprising: a first pulley rotatable about a first pulley axis, a first cable portion wrapped around the first pulley, such that, when the first pulley is rotated in a first direction about the first pulley axis, the first cable portion is unwound from the first pulley, and a second cable portion wrapped around the first pulley, such that, when the first pulley is rotated in the first direction about the first pulley axis, the second cable portion is wound further onto the first pulley, wherein the first and second cable portions form a continuous cable passing radially through the first pulley.

Abstract: The present disclosure provides position detector for an electric machine. The detector uses one or more proximity sensors, such as eddy current sensors, to detect features on the rotor of an electric machine. The detectable feature may be a spiral groove, which has a unique position at any given point around the circumference of the rotor. As the rotor is typically steel, the proximity sensors produce different output values depending on the degree to which they are aligned with the groove. As such, given that the groove has a unique position at any given location, the output of the proximity sensors is also unique for any given position. This enables the position of the rotor with respect to the sensors to be determined.

Abstract: A magnetic biasing assembly comprising: an inner element comprising: a north polarised inner arc, and a south polarised inner arc disposed axially adjacent to the north polarised inner arc, and an outer element arranged to rotate relative to the inner element about an axis, the inner and outer elements being substantially concentric, the outer element comprising: a north polarised outer arc, and a south polarised outer arc disposed axially adjacent to the north polarised outer arc, wherein the inner and outer polarised arcs are arranged so as to have a stable equilibrium position and are arranged to exert a magnetic moment between the inner and outer elements in a direction towards the stable equilibrium position when the inner and outer elements are not in the stable equilibrium position.