Format

COUPLER(id, jflag, comp, RM)

Description

Returns force component due to Constraint_Coupler element in reference frame of marker RM. jflag indicates whether force acting on I or J marker is desired.  The Constraint_Coupler element can involve either 4 markers for 2-joint couplers (I, J on the first joint and I, J on the second joint) or 6 markers for 3-joint couplers (I, J on the first joint, I, J on the second joint, and I, J on third joint).

Example

<Post_Request

  comment   = "frc-expr"

  id        = "70000044"

  type      = "EXPRESSION"

  expr1     = "COUPLER(10,0,1, 20)"

  expr2     = "COUPLER(10,0,2, 20)"

  expr3     = "COUPLER(10,0,3, 20)"

  expr4     = "COUPLER(10,0,4, 20)"

  expr5     = "COUPLER(10,0,5, 20)"

  expr6     = "COUPLER(10,0,6, 20)"

  expr7     = "COUPLER(10,0,7, 20)"

  expr8     = "COUPLER(10,0,8, 20)"

/>

This request element stores the COUPLER element forces into column vectors F1 through F8 of the request "frc-expr".

Arguments

id

The ID of the Constraint_Coupler element.

jflag

jflag = 0: forces/torques on the I marker of the first joint associated with the 2- or 3-joint coupler.

jflag = 1: forces/torques on the J marker of the first joint associated with the 2- or 3-joint coupler.

jflag = 2: forces/torques on the I marker of the second joint associated with the 2- or 3-joint coupler.

jflag = 3: forces/torques on the J marker of the second joint associated with the 2- or 3-joint coupler.

jflag = 4: forces/torques on the I marker of the third joint associated with the 3-joint coupler.

jflag = 5: forces/torques on the J marker of the third joint associated with the 3-joint coupler.

component

1 returns the force magnitude.

2 returns the force x component.

3 returns the force y component.

4 returns the force z component.

5 returns the torque magnitude.

6 returns the torque x component.

7 returns the torque y component.

8 returns the torque z component.

RM

The reference frame in which components are reported. RM=0 implies global frame.