Computes and scales string pot deflections at all four wheels then calculates the roll and pitch of the body on the suspension. This routine is useful in correlating an Adams model to actual vehicle test data which involves string pot measurements at all four wheels. All string pot deflections, roll angle, and pitch angle are normalized to zero at TIME = 0.
Input:
REQ/id, FUNCTION = USER (1115,lfbm,lfwm,rfbm,rfwm,lrbm,lrwm,rrbm,rrwm,scale)
where:
| | Description |
|---|
lfbm | = | left front string pot body MARKER id |
lfwm | = | left front string pot wheel MARKER id |
rfbm | = | right front string pot body MARKER id |
rfwm | = | right front string pot wheel MARKER id |
lrbm | = | left rear string pot body MARKER id |
lrwm | = | left rear string pot wheel MARKER id |
rrbm | = | right rear string pot body MARKER id |
rrwm | = | right rear string pot wheel MARKER id |
scale | = | scale factor to by multiplied to string pot displacements (e.g. scale = 1.0 for millimeters and for inches scale = .03937) |
Request File Output
Column Number Output :
1. Scaled left front string pot deflection
2. Scaled right front string pot deflection
3. Scaled left rear string pot deflection
4. Scaled right rear string pot deflection
5. Body-on-chassis roll angle (deg)
6. Body-on-chassis pitch angle (deg)
Notes on Input and Output
The scale factor can take any positive or negative value. Also, the equation for the roll and pitch angles are:
Roll = (ATAN((rfspd - lfspd) / fdy) + ATAN((rrspd - lrspd) / rdy))/2
Pitch = ATAN ( 0.5 * (rfspd + lfspd - rrspd - lrspd) / wbase ))
where:
| | Description |
|---|
rfspd | = | right front string pot deflection |
lfspd | = | left front string pot deflection |
rrspd | = | right rear string pot deflection |
lrspd | = | left rear string pot deflection |
fdy | = | lateral distance between front string pots |
rdy | = | lateral distance between rear string pots |
wbase | = | vehicle wheelbase |
The sign convention is:
Positive displacement: Wheel in rebound
Negative displacement: Wheel in jounce