Work machine

1. A work machine comprising:

a work device;

a plurality of actuators that drive the work device;

an operation device that operates the plurality of actuators; and

a controller that controls driving of at least one of the plurality of actuators,

wherein the controller is configured to

generate a supplemented design face that passes through a junction or above the junction between a first design face and a second design face adjacent to each other among a plurality of design faces prescribed on an operation plane of the work device, the supplemented design face having one end thereof positioned on the first design face and another end thereof positioned on the second design face,

set a curvature of the supplemented design face according to an operation amount of the operation device,

set a target face on the supplemented design face, and

execute semi-automatic excavation control to control at least one of the plurality of actuators such that a working point set on the work deice is maintained on the target face or above the target face.

2. The work machine according to claim 1 ,

wherein the controller is configured to

approximate the supplemented design face by a plurality of planes, and

execute the semi-automatic excavation control by setting one of the plurality of planes as the target face.

3. The work machine according to claim 1 ,

wherein the controller is configured to set the curvature of the supplemented design face such that a relation of the curvature of the supplemented design face relative to the operation amount of the operation device is a monotonous decrease relation.

4. The work machine according to claim 1 ,

wherein the controller is configured to

stop generation of the supplemented design face if the operation amount of the operation device is less than a predetermined value, and

set the curvature of the supplemented design face such that a relation of the curvature of the supplemented design face relative to the operation amount of the operation device is a monotonous decrease relation if the operation amount of the operation device is equal to or more than the predetermined amount.

5. The work machine according to claim 4 ,

wherein the predetermined value is a value of an operation amount for an actuator to start operation, the actuator being one corresponding to an operation to the operation device among the plurality of actuators.

6. The work machine according to claim 1 ,

wherein

the controller is configured to set a face having a first arcuate surface and a second arcuate surface as the supplemented design face if a shape of the junction between the first design face and the second design face is upwardly protruding and the work device is moved from one side toward another side on the operation plane,

the first arcuate surface having one end thereof connected to an end portion of a design face on the one side, of the first design face and the second design face, at the same inclination as that of the design face on the one side,

the second arcuate surface having one end thereof connected to another end side of the first arcuate surface and another end thereof connected to a design face on the other side, of the first design face and the second design face, at the same inclination as that of the design face on the other side.

7. The work machine according to claim 1 ,

wherein the controller is configured to

calculate distances between the respective ones of the first design face and the second design face and the working point,

calculate a distance between the working point and a vicinity point nearest to the working point on the supplemented design face, and

execute the semi-automatic excavation control by selecting one with the smallest distance to the working point among the first design face, the second design face, and the vicinity point, and setting the selected design face or a tangent at the selected vicinity point as the target face.

8. The work machine according to claim 2 ,

wherein the controller is configured to execute the semi-automatic excavation control by calculating distances between the respective ones of the plurality of planes and the working point, and setting a plane with the smallest distance to the working point, of the plurality of planes, as the target face.

9. The work machine according to claim 1 ,

wherein the controller is configured to change the curvature of the supplemented design face according to a position on the supplemented design face.