# Mechanism load

Every delivery into a target of this kind is summed.

## Interfaces

| Name | Kind | Units | Frame | Shape | Sign | Typical magnitude | Description |
|---|---|---|---|---|---|---|---|
| `apparatus.link_wrench` | load | N; N m | world | -1 x 6 | on the body each frame is fixed to, about the frame's origin | 0.001 | the loads on a chain segment's frames, one row per frame in the order the segment lists them: [force; torque about the frame's origin], summed over every delivery. The load target a dynamic segment offers, which a kinematic one does not |
| `body.applied_wrench` | load | N; N m | world | 6 | on the body, about its centre of mass | 1e-06 | [force; torque], summed over every law that loads the body |
| `body.background_load` | load | N; N m | world | 6 | on the body, held still in the ambient flow, about its centre of mass | 1e-06 | [force; torque] from the ambient flow, paired with a resistance |
| `toy.body.load` | load | N | world | 3 | on the body | 1 | the summed load on a toy body |
| `toy.body.torque` | load, reserved | N m | world | open (reserved) | on the body | none | reserved, to exercise the refusal of a reserved name |

## Dynamics that accept it

- [`rigid_inertial`](../entries/dynamics/rigid_inertial.md)
- [`toy.anchored_body`](../entries/dynamics/toy.anchored_body.md)
- [`toy.body`](../entries/dynamics/toy.body.md)

## Entries that deliver into it

- [`drag`](../entries/interaction/drag.md)
- [`gravity`](../entries/interaction/gravity.md)
- [`labx.nudge`](../entries/interaction/labx.nudge.md)
- [`magnetic.force`](../entries/interaction/magnetic.force.md)
- [`magnetic.torque`](../entries/interaction/magnetic.torque.md)
- [`toy.drag`](../entries/interaction/toy.drag.md)
- [`toy.lift`](../entries/interaction/toy.lift.md)
- [`toy.spring`](../entries/interaction/toy.spring.md)
- [`toy.twist`](../entries/interaction/toy.twist.md)

## The algorithm between nodes

No hand-written part: the cross-node algorithm of this mechanism is not written yet.