Static Optimization with Controlled Actuator?

[Andrea Willson]

I am trying to prescribe a force to a path actuator in a gait model during Static Optimization, and I'm wondering if this is even possible? If it is, I'm not sure why it's not working for me.

The Static Optimization setup files I have (saved from using the GUI) have these lines:
<ControllerSet name="Controllers">
<objects />
<groups />
</ControllerSet>

In this section of the xml file I added a Prescribed controller, which calls up a *.STO file with the control signal for the path actuator:
<ControllerSet name="Controllers">
<objects>
<PrescribedController name = "BPspringcontrol">
<!--Flag (true or false) indicating whether or not the controller is disabled.-->
<isDisabled>false</isDisabled>
<!--The list of model actuators that this controller will control.The keyword ALL indicates the controller will controll all the acuators in the model-->
<actuator_list></actuator_list>
<!--Functions (one per control) describing the controls for actuatorsspecified for this controller.-->
<FunctionSet name="ControlFunctions">
<objects />
<groups />
</FunctionSet>
<!--Controls storage (.sto) file containing controls for individual actuators in the model. Column labels must match actuator names.-->
<controls_file>controls3.sto</controls_file>
<!--Interpolate the controls file data using piecewise: '0-constant', '1-linear', '3-cubic' or '5-quintic' functions.-->
<interpolation_method></interpolation_method>
</PrescribedController>
</objects>
<groups />
</ControllerSet>

I followed the simtk guidelines to setup my controls (.sto) file: matching header, first column is always time, and Column title matches the actuator name, but when I run static optimization I get an error saying it could not open the controls file.
I can't find any documentation of someone having prescribed force to an actuator in Static Optimization, so I'm not sure if there really is some odd problem with my controls.sto file, or if thats just a general error message because controllers cannot be used in static optimization. Any help would be greatly appreciated! Thanks.

[jimmy d]

Prescribed force (PrescribedForce) and prescribed controls (PrescribedComtroller) are two different things, so it is useful to figure out which one you actually need.

Have you tried using the absolute path (C:/OpenSim/SO/control3.sto) of the .sto file, rather than the relative path (control3.sto)?

[RAHUL GHARATE]

Also I want to control the path actuator and I need to know where and what phase it is actuated. I copy above program and paste in a scripting shell window but it is not run. How and where we have to put this program and how to get controller for path actuator and how we confirm at what instance actuator actuates?
Please reply.