How can I produce a Torque signal to activate an External Force and Torque simulink block?

Hi!

I am currently working on a simulink model that must provide a basic simulation of a rotating helicopter blade. I have been using revolute joints, and what I want

to do is provide a rotating motion to the blade with an External Force and Torque Block. I want to now the rotating speed of the blade, and I thought I could attempt

to model an engine which could provide that torque signal to the External Force and Torque Block and also allow me to know the rotating speed.

I have tried several different things, and I can't manage to get it to work.

¿Could somebody help me out?

Answer 1

[J Chen]

Connect a Solid to a Revolute joint. Change the Actuation-Torque property of the Revolute Joint to Provided by Input. You then apply the sum of engine and aero torques to the torque input of the Revolute Joint block using a PS Constant or Constant and Simulink to PS Converter.

[Nicolás Capmany]

Hi!

Thank you very much for your quick reply! I tried to se both of them, but I keep getting the error showed by the image attached, and I can't understand why.

Has this happened to you before?

I have attached more images with the settings in order to make it easier to check the problem. I want the actuator to make the revolute joint rotate at a certain speed, as it represents the rotor of a helicopter blade, but it says that the input expected must be in radians.

[J Chen]

The blade.slx is a Simulink model, not a image file.

The unit of the PS Constant block should be rad instead of rad/s. The Revolute Joint block needs a position input, not speed. Add an integrator between the PS Constant block and the Revolute Joint block if you want to use the PS Constant block to specify speed. You probably can keep the rad/s unit in this case. You can also completely eliminate the unit to keep it simple.

[Nicolás Capmany]

Hi!

Thanks for your quick answer once again. I am afraid I sill get simulink error which I do not know how to solve.

I had uploaded an image of what I am trying to do. I want that revolute joint to rotate at a 2*pi (rad/s) to simulate the blade's rotation, but I keep getting a mistake which is on the other image attached, and Im wondering what am I doing wrong.

Thank you very much in advance for all your help!

[J Chen]

Add a derivative in the Simulink-PS Converter (in the Input Handling tab)

[J Chen]

Did the solution work? Please accept the answer if it did. Thanks.