Patent ID: 8832875

Claim:
A transfer assist apparatus comprising: an arm portion that has a first joint and a second joint; a holder portion linked to the arm portion; a manipulation handle for manipulating position of the holder portion; a first drive mechanism that rotationally drives the first joint; a second drive mechanism that rotationally drives the second joint, wherein a rotation axis about which the first joint is rotated is parallel to a rotation axis about which the second joint is rotated, and wherein the position and posture of the holder portion is determined by an angle of the first joint and an angle of the second joint; a memory that stores data showing a correspondence between a predicted position of the holder portion, which is calculated based on information that is input from the manipulation handle, and an acceptable posture range at the predicted position; and a control portion that receives angle measurements from at least one rotation sensor and that is programmed to determine a target angle of the first joint and a target angle of the second joint so as to satisfy the acceptable posture range if a predicted posture of the holder portion at the predicted position is outside the acceptable posture range, wherein the control unit is further programmed to control the first drive mechanism and the second drive mechanism so that the angle of the first joint matches the target angle of the first joint and the angle of the second joint matches the target angle of the second joint, wherein the control portion performs a control so as to hold the posture of the holder portion while the position of the holder portion is above a predetermined height, and wherein a tentative target value of the joint angle of the second joint which is being manipulated by the manipulation handle is calculated on the basis of the amount of manipulation, and a target value of the joint angle of the first joint which is not being manipulated is automatically determined to maintain the posture of the holder portion in the predetermined acceptable range.