Actuator with joints

摘要

Implementations and techniques are generally disclosed for an actuator comprising: a first element, a second element, a third element, a first joint provided between the first element and the second element, a second joint provided between the second element and the third element, and a motor operably coupled to the first joint and configured such that the second element rotates with respect to the first element about a first rotational axis when the motor rotates, wherein the first joint is operably coupled to the second joint and configured such that the third element can rotate with respect to the second element about a second rotational axis when the motor rotates.

主权项

1. An actuator comprising:
a motor; a first element; a second element; a third element; a first joint provided between the first element and the second element and adapted such that the second element is rotatable with respect to the first element about a first rotational axis, wherein the first joint includes:
two first crown gears configured to oppose each other and to rotate about the first rotational axis, wherein one of the two first crown gears is operably coupled to the motor;a first spur gear configured to engage with the two first crown gears and to rotate about the first rotational axis such that the two first crown gears rotate in opposite directions when the first spur gear rotates; andtwo first thrust bearings provided between the first element and the corresponding first crown gears; a second joint provided between the second element and the third element and adapted such that the third element is rotatable with respect to the second element about a second rotational axis, wherein the second joint includes:
two second crown gears configured to oppose each other and to rotate about the second rotational axis;a second spur gear configured to engage with the two second crown gears such that the two second crown gears rotate in opposite directions when the second spur gear rotates; andtwo second thrust bearings provided between the second element and the corresponding second crown gears; two first clutch mechanisms provided between the first element and the second element, wherein one of the first clutch mechanisms is configured to selectively engage or disengage between a rotational shaft of one of the first crown gears and the second element, and wherein another of the first clutch mechanisms is configured to selectively engage or disengage between a rotational shaft of another of the first crown gears and the second element; two second clutch mechanisms provided between the second element and the third element, wherein one of the second clutch mechanisms is configured to selectively engage or disengage between a rotational shaft of one of the second crown gears and the third element, and wherein another of the second clutch mechanisms is configured to selectively engage or disengage between a rotational shaft of another of the second crown gears and the third element; an intermediate drive mechanism provided between the first joint and the second joint, wherein the intermediate drive mechanism includes an intermediate spur gear configured to engage with one of the first crown gears of the first joint and operably coupled to the second spur gear of the second joint such that the second spur gear of the second joint rotates when one of the first crown gears of the first joint rotates; two first rotary encoders coupled to corresponding ones of the two first crown gears of the first joint and configured to generate first output signals; two second rotary encoders coupled to corresponding ones of the second crown gears of the second joint and configured to generate second output signals; and a controller configured to control the motor, the first clutch mechanism, and the second clutch mechanism based on the first and second output signals from the first and second rotary encoders such that the first element rotates with respect to the second element by a first target angle with a first target rotational speed and the second element rotates with respect to the third element by a second target angle with a second target rotational speed.