Remarks and Known Issues
■Concurrent SIMulation Workbench Environment: The CPU clockspeed is important for execution times of the model. Simulating with Concurrent SIMulation Workbench, the 'cruising' compliance vehicle model in combination with a 3.5 GHz clockspeed CPU needs approximately 1.2 ms execution, whereas a 2.7 GHz clockspeed CPU needs approximately 1.8 ms execution time in the current Solver implementation. For this reason it is advisable to increase the "Fixed Step" setting in the SimWB Control Center "Tests" tab from the default of 1 ms to 2 or more ms so Adams has enough time to execute without causing too many overruns.
■A torque feedback option for the steering wheel is available but not illustrated in this example. However, this example model may not be equipped in providing realistic torque feedback.
■The steering wheel angle input signal is passed through an exponential smoothing function and Butterworth filter (modelled by an TFSISO).
The exponential smoothing function is modelled as follows:
! adams_view_name='Controls_IO.steering_expsmooth'
VARIABLE/314
, FUNCTION = USER(steering_input ID, par_a, par_g)\
, ROUTINE = abgVDM::varExpSmooth
with steering_input in [rad] and the smooth steering wheel angle computed as follows:
steering_expsmooth = par_a*( steering_expsmooth_old + b_old + (1-par_a)*steering_input
b=par_g*b_old + (1-par_g)*(steering_expsmooth-steering_expsmooth_old)
■The Solver step size when using Adams Car is determined by the following parameters:
■stepSize (.xml Event file, section dcf:DcfMini): Specifies the Adams Solver Output step size.
■samplePeriod (.xml Event file, section dcf:DcfMachine): Specifies the Driving Machine discrete GSE sample time (default = 0.01s).
■Hmax (Adams Solver setting): Maximum time step that the Solver is allowed to take.