# question to AnyKinEqSimpleDriver

I have a question about AnyKinEqSimpleDriver.

AnyKinEqSimpleDriver Actuator = {
AnyRevoluteJoint &Jnt = Main.SliderCrank.Jnts.Shaft;
DriverPos = {0.0};
DriverVel = {6.28};

My aim is to calculate joint forces in the Demo.SliderCrank3D.any file.
But IÂ´m confused about my results. Now IÂ´m not sure if I understand
the driver well.
-The driver owns a constant acceleraton (Reference Manual), but how
big is this and how long is the rotation time, just 1 second? Where
and how can I define acceleration and time?
-What is really the meaning of DriverVel = {6.28} ? Just the velocity
at t=0 (Reference Manual)?

Thanks
JÃ¼rg Leemann

Hello JÃ¼rg and welcome to the AnyScript Group!

> -The driver owns a constant acceleraton (Reference Manual), but how
> big is this and how long is the rotation time, just 1 second? Where
> and how can I define acceleration and time?

The default value of the acceleration is zero, so unless you specify

DriverAcc = {something};

you will get a driver moving at constant speed. If, for instance,
you specify

DriverAcc = {pi};

then at t = 0.3 second the speed will be 2pi + 0.3pi = 2.3*pi.

The time is controlled in the study at the bottom of th example
file. The study has a tStart and a tEnd (defauting to 0 and 1 second
respectively). If ou want the simulation to run further, simple
specify, for instance

tEnd = 2.0;

in the study.

> -What is really the meaning of DriverVel = {6.28} ? Just the
velocity at t=0 (Reference Manual)?

This means that the driver velocity is 6.28 (= 2*pi) at time t = 0.
If there is no acceleration specified, then this is a constant speed
that applies for all times.