Robot.plan_motion

Robot.plan_motion(goal_constraints, start_configuration=None, group=None, options=None)[source]

Calculate a motion path.

Parameters

• goal_constraints (list of Constraint) – The goal to be achieved, defined in a set of constraints. Constraints can be very specific, for example defining value domains for each joint, such that the goal configuration is included, or defining a volume in space, to which a specific robot link (e.g. the end-effector) is required to move to.

• start_configuration (Configuration, optional) – The robot’s full configuration, i.e. values for all configurable joints of the entire robot, at the starting position. Defaults to the all-zero configuration.

• group (str, optional) – The name of the group to plan for. Defaults to the robot’s main planning group.

• options (dict, optional) – Dictionary containing the following key-value pairs:

  • path_constraints :: list of Constraint, optional

    Optional constraints that can be imposed along the solution path. Note that path calculation won’t work if the start_configuration violates these constraints. Defaults to None.

  • attached_collision_meshes :: list of compas_fab.robots.AttachedCollisionMesh

    Defaults to None.

  There are additional options that are specific to the backend in use. Check the API reference of the motion planner backend implementation for more details.

Returns

JointTrajectory – The calculated trajectory.

Examples

Using position and orientation constraints:

>>> robot.client = RosClient()
>>> robot.client.run()
>>> frame = Frame([0.4, 0.3, 0.4], [0, 1, 0], [0, 0, 1])
>>> tolerance_position = 0.001
>>> tolerances_axes = [math.radians(1)] * 3
>>> start_configuration = Configuration.from_revolute_values([-0.042, 4.295, 0, -3.327, 4.755, 0.])
>>> group = robot.main_group_name
>>> goal_constraints = robot.constraints_from_frame(frame, tolerance_position, tolerances_axes, group)
>>> robot.attached_tool = None
>>> trajectory = robot.plan_motion(goal_constraints, start_configuration, group, {'planner_id': 'RRTConnectkConfigDefault'})
>>> trajectory.fraction
1.0
>>> len(trajectory.points) > 1
True
>>> robot.client.close()

Using joint constraints (to the UP configuration):

>>> robot.client = RosClient()
>>> robot.client.run()
>>> configuration = Configuration.from_revolute_values([0.0, -1.5707, 0.0, -1.5707, 0.0, 0.0])
>>> tolerances_above = [math.radians(5)] * len(configuration.values)
>>> tolerances_below = [math.radians(5)] * len(configuration.values)
>>> group = robot.main_group_name
>>> goal_constraints = robot.constraints_from_configuration(configuration, tolerances_above, tolerances_below, group)
>>> trajectory = robot.plan_motion(goal_constraints, start_configuration, group, {'planner_id': 'RRTConnectkConfigDefault'})
>>> trajectory.fraction
1.0
>>> len(trajectory.points) > 1
True
>>> robot.client.close()