Operation method for link actuating device

1. An operation method for a link actuating device,

the link actuating device including:

a proximal end side link hub;

a distal end side link hub; and

a link mechanism which connects the distal end side link hub to the proximal end side link hub such that a posture of the distal end side link hub can be changed relative to the proximal end side link hub;

an actuator provided in the link mechanism, the actuator changing a distal end posture that is the posture of the distal end side link hub relative to the proximal end side link hub:

a control device configured to control the actuator; and

an end effector mounted to the distal end side link hub, the end effector being configured to work a three-dimensional workpiece,

the operation method being configured to input a target value to which the distal end posture is changed,

the link actuating device further including:

a target value input unit configured to input the target value by use of a three-dimensional rectangular coordinate on a three-dimensional rectangular coordinate system, which three-dimensional rectangular coordinate system has an origin on a central axis of the proximal end side link hub; and

an input converter configured to calculate the distal end posture of the link actuating device by using a value inputted from the target value input unit, calculate a command operation amount of each actuator from a result of the calculation, and input the command operation amount to the control device, which distal end posture is represented by a bend angle and an angle of swing, the bend angle being a vertical angle formed when a central axis of the distal end side link hub is inclined relative to the central axis of the proximal end side link hub, the angle of swing being a horizontal angle formed when the central axis of the distal end side link hub is inclined relative to the central axis of the proximal end side link hub,

the operation method comprising:

obtaining the three-dimensional rectangular coordinate of the three-dimensional rectangular coordinate system on which the end effector work can be easily calculated from a CAD data of the three-dimensional workpiece, and then, inputting the obtained three-dimensional rectangular coordinate to the target value input unit as the target value; and

calculating the distal end posture, from the three-dimensional rectangular coordinate inputted as the target value, with use of the input converter, and then, calculating the command operation amount of the actuator from the result of the calculation, so as to input the calculated command operation amount to the control device.

2. The operation method for the link actuating device as claimed in claim 1 , wherein

three or more link mechanisms are provided, and

each of the link mechanisms includes:

a proximal side end link member having one end rotatably connected to the proximal end side link hub;

a distal side end link member having one end connected to the distal end side link hub; and

an intermediate link member having opposed ends thereof being rotatably connected to other ends of the proximal side end link member and the distal side end link member, respectively,

each of the link mechanisms has such a shape that a geometric model of the link mechanism represented by straight lines shows symmetry between a proximal end side portion thereof and a distal end side portion thereof with respect to a center portion of the intermediate link member, and

the actuator is provided in the two or more link mechanisms among the three or more link mechanisms.