How can I link the hydraulic model to the mechanical model?

I am developing a hydraulic model that moves a mechanical model such as a forklift. How can I connect a single-acting hydraulic cylinder to a mechanical model correctly?

Answer 1

[Altaïr]

Hey @Zeko Zain,

The 'Single-Acting Hydraulic Cylinder' block features 4 ports, each with a specific role:

• R: Connects the cylinder rod to the mechanical system.
• C: Connects the cylinder clamp/head to the mechanical system.
• A: Hydraulic connection to the cylinder’s inlet.
• P: The piston’s position as a physical signal.

The 'Single-Acting Cylinder with 3-Way Valve' example might be quite relevant to your use case. To access the documentation page, run this command in the MATLAB Command Window:

web(fullfile(docroot, 'physmod/hydro/examples/single-acting-cylinder-with-3-way-valve.html')) 

A simplified version of the example is available in the attached file 'example_R2018b.slx'. In this model, the spring mass damper system represents the mechanical translational components of a forklift.

A step signal is used to open the valve at 5 seconds, causing the cylinder rod to extend.

Note that single-acting cylinders transfer force and motion in only one direction. An external device, like a spring, weight, or another oppositely installed cylinder, is needed to move the rod in the opposite direction.

Alternatively, the 'Translational Hydro-Mechanical Converter' can be used. The relevant documentation can be accessed with the following command:

web(fullfile(docroot, 'physmod/simscape/ref/translationalhydromechanicalconverter.html'))