Robotics/EndEffectors/SuctionCup.openplx
SuctionCup

SuctionCup is Physics3D.StructuralComponent:
    .doc: """
A suction cup has object_connector at its origin with the purpose
to use SNAP position objects at the lip of the cup.
The characteristics of the flexible cup are considered to be different in the relaxed and collapsed state.
Therefore there are two mate connectors for attaching the cup to the vacuum gripper.
It is up to the runtime environment to swap between two states, both should not be active simultaneously.

The mounting_radius define the area for airflow through the top of the cup.
The lip_radius define the area for gripping.
The resting_height is the height of the cup when not exposed to any external forces.
The collapsed_height is the height of the cup when an object is grasped, and the cup has collapsed.

The body of the gripper_connector should point to the body of the gripper to which the cup is connected.

The origin of the body shold be at the surface of the imagined lip of the cup.
The local body position is by default at negative resting_height relative the cup system along the lip_normal.
The local_transform of the cup relative its parent system, i.e. the gripper, is required for positioning it.
"""
    body is Physics3D.Bodies.RigidBody:
        kinematics.local_transform.position: lip_normal * resting_height
    lip_radius is Real
    mounting_radius is Real
    resting_height is Real
    collapsed_height is Real

    lip_normal is Math.Vec3: Math.Vec3.from_xyz(0,0,-1)

    gripper_connector is Physics3D.Charges.RedirectedMateConnector:
        main_axis: Math.Vec3.from_xyz(0,0,-1)
        position: Math.Vec3.from_xyz(0,0,0)

    resting_mounting_connector is Physics3D.Charges.RedirectedMateConnector:
        redirected_parent: body
        main_axis: Math.Vec3.from_xyz(0,0,-1)
        position: Math.Vec3.from_xyz(0,0,0)

    collapsed_mounting_connector is Physics3D.Charges.RedirectedMateConnector:
        redirected_parent: body
        main_axis: Math.Vec3.from_xyz(0,0,-1)
        position: -lip_normal.normal() * collapsed_height

    object_connector is Physics3D.Charges.RedirectedMateConnector:
        redirected_parent: body
        main_axis: Math.Vec3.from_xyz(0,0,-1)
        position: lip_normal * (resting_height)