US 12,285,864 B2
Link actuation device and method for driving link actuation device
Akihiro Hayashi, Iizuka (JP); Hirofumi Fukumaru, Iizuka (JP); and Toshiki Takaki, Iwata (JP)
Assigned to KYUSHU INSTITUTE OF TECHNOLOGY, Kitakyushu (JP); and NTN Corporation, Osaka (JP)
Filed by KYUSHU INSTITUTE OF TECHNOLOGY, Kitakyushu (JP); and NTN Corporation, Osaka (JP)
Filed on Mar. 9, 2023, as Appl. No. 18/181,291.
Claims priority of application No. 2022-038289 (JP), filed on Mar. 11, 2022.
Prior Publication US 2023/0286138 A1, Sep. 14, 2023
Int. Cl. G06F 17/18 (2006.01); B25J 9/00 (2006.01); B25J 9/16 (2006.01)
CPC B25J 9/1605 (2013.01) [B25J 9/0048 (2013.01); G06F 17/18 (2013.01)] 4 Claims
OG exemplary drawing
 
1. A link actuation device comprising:
a first link hub adjacent to a proximal end;
a second link hub adjacent to a distal end;
at least three link mechanisms that couple the first link hub and the second link hub;
a drive device that drives the at least three link mechanisms; and
a control device that controls the drive device, wherein
the drive device includes motors provided for the at least three link mechanisms, respectively,
each of the at least three link mechanisms includes
a first end link member rotatably coupled to the first link hub,
a second end link member rotatably coupled to the second link hub, and
a center link member rotatably coupled to both the first end link member and the second end link member,
in the at least three link mechanisms,
at least three center axes of revolute pairs of the first link hub and the first end link members and a center axis of a revolute pair of one end of each of the center link members intersect at a first link hub center point, and
at least three center axes of revolute pairs of the second link hub and the second end link members and a center axis of a revolute pair of an other end of each of the center link members intersect at a second link hub center point,
the control device stores a map in which drive command values for each of the motors corresponding to a plurality of discrete positions within a movable range of the second link hub are stored, and
upon receipt of a command value for movement to a position that coincides with none of the plurality of positions within the movable range, the control device determines a drive command value for each of the motors by interpolating a region surrounded by four points at the plurality of positions on the map using a polynomial curved surface formula.