Motion path generation device, motion path generation method, and non-transitory tangible computer readable storage medium

A motion path generation method configured to generate a motion path of a robot that has a plurality of joints and a plurality of shafts, adjacent two of the plurality of shafts being connected by a corresponding one of the plurality of joints, the motion path generation method comprising;

• selecting, from a predetermined via point, a parent via point that is a source for searching for a next via point in a joint space, each axis of the joint space defining an angle of each of the plurality of joints, an attitude of the robot being represented by a coordinate in the joint space;
• setting a search area for searching for the next via point;
• randomly generating a via point candidate that is a candidate of the next via point to be connected to the parent via point;
• determining whether the via point candidate interferes with an obstacle;
• and
• adding the via point candidate as a new via point in response to determining that the via point candidate does not interfere with the obstacle, wherein
• the setting of the search area in the joint space includes setting of a change angle range of each of the plurality of joints such that an amount of movement of all of the plurality of shafts does not exceed a maximum movement amount,
• the maximum movement amount is defined as an amount of movement of at least one of the plurality of shafts which is smaller than a maximum possible movement amount, and
• the maximum possible movement amount is an amount of movement of all of the plurality of shafts when each of the plurality of joints changes by a specified maximum angle.

A non-transitory tangible computer readable storage medium comprising instructions executed by a processor of a motion path generation device, the motion path generation device configured to generate a motion path of a robot that has a plurality of joints and a plurality of shafts, adjacent two of the plurality of shafts being connected by a corresponding one of the plurality of joints, the instructions comprising:

• selecting, from a predetermined via point, a parent via point that is a source for searching for a next via point in a joint space, each axis of the joint space defining an angle of each of the plurality of joints, an attitude of the robot being represented by a coordinate in the joint space;
• setting a search area for searching for the next via point;
• randomly generating a via point candidate that is a candidate of the next via point to be connected to the parent via point;
• determining whether the via point candidate interferes with an obstacle;
• and
• adding the via point candidate as a new via point in response to determining that the via point candidate does not interfere with the obstacle, wherein
• the setting of the search area in the joint space includes setting of a change angle range of each of the plurality of joints such that an amount of movement of all of the plurality of shafts does not exceed a maximum movement amount,
• the maximum movement amount is defined as an amount of movement of at least one of the plurality of shafts which is smaller than a maximum possible movement amount, and
• the maximum possible movement amount is an amount of movement of all of the plurality of shafts when each of the plurality of joints changes by a specified maximum angle.