Adams Car Package > Adams Car > Appendix > Solver Routines > Quasi-Static Steady-State Straight Line Acceleration/Braking Equilibrium

Quasi-Static Steady-State Straight Line Acceleration/Braking Equilibrium

The quasi-static steady-state straight line acceleration/braking equilibrium CONSUB is similar to Static Steady-State Straight Line Acceleration/Braking Equilibrium except it can be employed to solve over a range of accelerations and decelerations. This option is useful for running the straight line braking or acceleration tests where simulations are required at different longitudinal accelerations. The balance of forces and all other functions of the static straight line equilibrium are the same for the quasi-static case. It is important to note that TIME is incremented in the graphics and request files for easy plotting.
The CONSUB can be invoked in the quasi-static steady-state straight line equilibrium mode by typing the following at the Adams promptor in the acf file:
CONTROL/FUN=USER (1021,jpr_ary,vel,brk_flg,end_g,nsteps,halt,origo)
where:
 
jpr_ary
=
Id of array containing the necessary jprims, motions, sforce ids to perform the static equilibrium 
vel
=
Logitudinal velocity of the vehicle 
brk_flg
=
flag to specify whether deceleration should be applied as braking or throttle off deceleration. For throttle off deceleration the applied deceleration is balanced by forces/moments generated at the driven wheels. For braking deceleration the deceleration is balanced by braking forces/moments at all wheels based on braking ratios (Car models only)
1 - braking deceleration
0 - throttle off deceleration (default)
end_g
=
final level of longitudinal acceleration/deceleration to impose on the vehicle 
positive value = acceleration 
negative value = deceleration 
nsteps
=
number of steps for the output (that is, acceleration increment = end_g / nsteps)
halt
=
(Optional) parameter to terminate or continue a simulation after a static failure.
1 - stop the simulation if static fails (default).
0 - continue the simulation if static fails.
origo
=
(Optional). Marker defining the coordinate system is which model was created. (Standard Adams Car models have vehicle forward as -X).Default marker id is 3
The first time this CONSUB is invoked, the initial g level is assumed to be zero. If the user invokes it a second time, the initial g level will be the end_g of the last call to this CONSUB.