# Motion constraints reference Configure constraints to specify certain types of motion. > Source: https://docs.viam.com/reference/services/motion/constraints/ You can constrain the motion of your machine using the motion service's built-in constraint options. Constraints are passed as arguments to the [`Move`](/reference/apis/services/motion/#move) method. The following constraints are available: - [Linear constraint](#linear-constraint) - [Orientation constraint](#orientation-constraint) - [Next steps](#next-steps) ## Linear constraint The linear constraint (`{"motion_profile": "linear"}`) forces the path taken by `component_name` to follow an exact linear path from the start to the goal. If the start and goal orientations are different, the orientation along the path will follow the quaternion [Slerp (Spherical Linear Interpolation)](https://en.wikipedia.org/wiki/Slerp) of the orientation from start to goal. This has the following sub-options: | Parameter Name | Type | Default | Description | | -------------- | ---- | ------- | ----------- | | line_tolerance_mm | float | 0.1 | Max linear deviation from straight-line between start and goal, in mm. | | orientation_tolerance_degs | float | 2.0 | Allowable deviation from Slerp between start/goal orientations, in degrees. | **Example usage**: ### Python ```python # Move a gripper with a linear constraint moved = await motion.move( component_name=my_gripper, destination=PoseInFrame( reference_frame="my_frame", pose=goal_pose), world_state=worldState, constraints={ Constraints( linear_constraint=[LinearConstraint(line_tolerance_mm=0.2)]) }, extra={}) ``` You can find more information in the [Python SDK Docs](https://python.viam.dev/autoapi/viam/gen/service/motion/v1/motion_pb2/index.html#viam.gen.service.motion.v1.motion_pb2.Constraints). ### Go ```go // Move a gripper with a linear constraint myConstraints := &servicepb.Constraints{LinearConstraint: []*servicepb.LinearConstraint{&servicepb.LinearConstraint{}}} moved := motionService.Move( context.Background(), myGripperResourceName, NewPoseInFrame("myFrame", myGoalPose), worldState, myConstraints, nil ) ``` You can find more information in the [Go SDK Docs](https://pkg.go.dev/go.viam.com/api/service/motion/v1#Constraints). ## Orientation constraint The orientation constraint (`{"motion_profile": "orientation"}`) places a restriction on the orientation change during a motion, such that the orientation during the motion does not deviate from the [Slerp](https://en.wikipedia.org/wiki/Slerp) between start and goal by more than a set amount. This is similar to the "orient_tolerance" option in the linear profile, but without any path restrictions. If set to zero, a movement with identical starting and ending orientations will hold that orientation throughout the movement. | Parameter Name | Type | Default | Description | | -------------- | ---- | ------- | ----------- | | orientation_tolerance_degs | float | 2.0 | Allowable deviation from Slerp between start/goal orientations, in degrees. | **Example usage**: ### Python ```python # Move a gripper with an orientation constraint moved = await motion.move( component_name=my_gripper, destination=PoseInFrame( reference_frame="my_frame", pose=goal_pose), world_state=worldState, constraints=Constraints(orientation_constraint=[OrientationConstraint()]), extra={}) ``` You can find more information in the [Python SDK Docs](https://python.viam.dev/autoapi/viam/gen/service/motion/v1/motion_pb2/index.html#viam.gen.service.motion.v1.motion_pb2.Constraints). ### Go ```go // Move a gripper with an orientation constraint myConstraints := &servicepb.Constraints{OrientationConstraint: []*servicepb.OrientationConstraint{&servicepb.OrientationConstraint{}}} moved := motionService.Move( context.Background(), myGripperResourceName, NewPoseInFrame("myFrame", myGoalPose), worldState, myConstraints, nil ) ``` You can find more information in the [Go SDK Docs](https://pkg.go.dev/go.viam.com/api/service/motion/v1#Constraints). ## Next steps Constraints are used in the following tutorials:
Claw Game

Create your own version of the famous arcade claw machine using a robotic arm and a claw grabber.

Add motion constraints

Use constraints and transforms with the motion service.