Giving position input to actuator and getting force output

Hello,

I have a linear actuator system that working with prismatic joint. I am using Servomotor on my system.

I am able to make the system work with force input but that is not my aim. My current aim is controlling the system with position input.

The thing I am trying to do is as a scenario; I will give 20mm, 10mm, 5mm +Z axis movement and going to meausere the force that created for this movement.

I have added Ideal Translational Motion Sensor to give position input, but it is just offseting the system at the beginning of the simulation. I have 2 main question regarding to that issue;

1- How can I use correctly the position input, the thing I am trying to do is making the system move in the simulation, not offsetting it at the beginning of the simulation.

2- I want to control the system from the window also, giving different input with a button. You can see the system I am trying to create on this video ( https://www.youtube.com/watch?v=egThLwGQqlk )

That is my current system ;

That is the system I want to create, basically I want to add this buttons to control my simulation. (10mm displacement, 5mm displacement 20 mm displacement)

Thanks for your help

Answer 1

[Kanishk]

Hi Fatih,

To achieve position control in the linear actuator system, ensure that the setup allows for position commands to be translated into movement accurately. Check for the following issues:

• Make sure that the “Ideal Translational Motion Sensor” is configured to provide feedback rather than act as a position offset. It should be part of the feedback loop, not a direct input.
• Check the initial conditions of your simulation to ensure that they are set to zero or the desired starting position, avoiding any unintended offsets at the beginning.

If the above suggestions do not resolve your issue, please feel free to share your model or provide more details about your setup.

To control the input during the simulation using GUI, ‘combo box’ block can be used.

‘Combo box’ provides Drop down functionality to set the value of parameter interactively.

Please go through the official MATLAB documentation of ‘combo box’ to learn more about it.

https://www.mathworks.com/help/releases/R2024a/simulink/slref/combobox.html

Hope this helps!

Thanks

[Fatih]

Hello, thanks for your suggestions.

If the “Ideal Translational Motion Sensor” is not a direct input, how can I give a direct position input to my system ?

Thanks for the combo box suggestion again.

[Kanishk]

Hey, Glad to help.

It is diffifult to answer without the model but it appears you have utilized a PID Controller, which can be employed to create a feedback loop with the addition of position input..

Can you specify more on what do you mean by "offseting the system at the beginning of the simulation"? Additionally, could you clarify your objectives for the model?

[Fatih]

Hey,

Thanks for your help.

I have attached the model. It is basically a slider moving in one axis.

My objective simulating the system. The moving part is going to move 20mm and I will measure position accuracy, time for the movement, and the force that need to move part 20mm.

When I give input as 60mm with ideal tranlational motion sensor, the simulation is starting from the 60mm.

Open to suggestions. Thank you