Arm device and cable deceleration device
Provided is an arm device in which a cable deceleration structure with improved degree of freedom of arrangement of a motor is applied to an active joint. The arm device includes one or more active shafts and includes an input capstan attached to an output shaft of a motor for driving at least one active shaft of the one or more active shafts, an output capstan attached to the at least one active shaft, an idler pulley disposed between the input capstan and the output capstan, and a cable wound around an outer periphery of each of the input capstan and the output capstan via the idler pulley.
1 . An arm device, comprising:
a first input capstan attached to a first output shaft of a first motor;
a first output capstan apart from the first input capstan;
a first idler pulley between the first input capstan and the first output capstan; and
a cable wound around an outer periphery of each of the first input capstan and the first output capstan via the first idler pulley, wherein the first idler pulley is adjacent to the first output capstan.
2 . The arm device according to claim 1 , further comprising:
a second input capstan attached to a second output shaft of a second motor;
a second output capstan rotatable about a common active shaft with the first output capstan;
a second idler pulley;
a first cable deceleration mechanism configured to transmit rotation of the first motor to the first output capstan by use of the first input capstan and the first idler pulley; and
a second cable deceleration mechanism configured to transmit rotation of the second motor to the second output capstan by use of the second input capstan and the second idler pulley.
3 . The arm device according to claim 2 , wherein
an arrangement of the first motor overlaps with an arrangement of the second output capstan, and
an arrangement of the second motor overlaps with an arrangement of the first output capstan.
4 . The arm device according to claim 2 , further comprising:
a third output capstan;
a third input capstan attached to a third output shaft of a third motor;
a third idler pulley; and
a third cable deceleration mechanism configured to transmit rotation of the third motor to the third output capstan by use of the third input capstan and the third idler pulley, wherein
the third output capstan is configured to:
drive a pan shaft based on the transmitted rotation of the third motor; and
control, based on the drive of the pan shaft, the arm device to perform a pan operation.
5 . The arm device according to claim 2 , further comprising:
a first link; and
a second link, wherein
the first output capstan is configured to drive the first link, and
the second output capstan is configured to drive the second link.
6 . The arm device according to claim 5 , wherein an end of each of the first link and the second link is configured to support one of a driving unit or an operation unit.
7 . The arm device according to claim 5 , wherein an arrangement of the first link is line-symmetric with an arrangement of the second link.
8 . The arm device according to claim 1 , wherein a radius of the first input capstan is smaller than a radius of the first motor.
9 . The arm device according to claim 8 , wherein the radius of the first motor includes a radius of an encoder integrated with the first motor and a brake integrated with the first motor.
10 . The arm device according to claim 1 , wherein
the cable is bundled within a proximity of the first input capstan and the first idler pulley, and
the cable is wound within the proximity of the first output capstan after the cable is bundled within the proximity of the first input capstan and the first idler pulley.
11 . The arm device according to claim 1 , wherein
the cable is wound within a proximity of the first idler pulley in a direction opposite to the first input capstan after the cable is wound within the proximity of the first input capstan, and
the cable is further wound within the proximity of the first output capstan in a direction opposite to the first idler pulley.
12 . The arm device according to claim 1 , wherein
two or more idler pulleys are between the first output capstan and the first input capstan, and
the two or more idler pulleys include the first idler pulley.
13 . The arm device according to claim 12 , further comprising two idler pulleys between the first input capstan and the first output capstan, wherein
the two or more idler pulleys include the two idler pulleys,
the first input capstan is between the two idler pulleys, and
the first input capstan is configured to approach the first output capstan from between the two idler pulleys.
14 . The arm device according to claim 12 , wherein
the cable is wound around the first input capstan,
the cable passes between two idler pulleys after the cable is wound around the first input capstan,
the cable is wound around the first output capstan after the cable passes between the two idler pulleys, and
the two or more idler pulleys include the two idler pulleys.
15 . The arm device according to claim 14 , wherein the cable is between the two idler pulleys and the first output capstan.
16 . The arm device according to claim 12 , wherein
the cable is bundled within a proximity of the first input capstan and two idler pulleys,
the cable is wound within the proximity of the first output capstan after the cable is bundled within the proximity of the first input capstan and the two idler pulleys, and
the two or more idler pulleys include the two idler pulleys.
17 . The arm device according to claim 1 , further comprising a pre-tension applying mechanism configured to apply pre-tension to the cable.
18 . The arm device according to claim 17 , wherein
the pre-tension applying mechanism includes a tension coil spring,
an end of the cable is coupled with the first output capstan via the tension coil spring.
19 . The arm device according to claim 1 , wherein the first input capstan has a spiral groove around which the cable winds.
20 . The arm device according to claim 1 , wherein the first idler pulley is adjacent to the first input capstan.
21 . The arm device according to claim 1 , wherein a rotation axis of the first idler pulley is substantially in a same direction as a rotation axis of the first output capstan.
22 . The arm device according to claim 21 , wherein the rotation axis of the first idler pulley is substantially in a same direction as a rotation axis of the first input capstan.
23 . The arm device according to claim 1 , wherein the arm device includes a plurality of active shafts.
24 . A cable deceleration device, comprising:
an input capstan attached to an output shaft of a motor;
an output capstan is apart from the input capstan;
an idler pulley between the input capstan and the output capstan; and
a cable wound around an outer periphery of each of the input capstan and the output capstan via the idler pulley, wherein
the idler pulley is adjacent to the output capstan.