Graham

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11 years, 21 days

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These are answers submitted by Graham

Hi Zhong Chen,

 

 Here is a MapleSim model which might help you out. The signal is sampled (discretized), and the max value is recorded. Perhaps you can use this within your model?

 

I hope this helps.

 

MaxWorking.msim

-Graham

Hi,

 

This may be a by-product of the “autoassemble” feature in MapleSim’s visualization. Try turning off this feature (Menu -> View/Auto-Assemble).

Hi Onder,

 

  MapleSim is capable of systems with multiple inputs and outputs. I wonder if there might be a problem with your model that needs debugging.

 

Thanks,

 

Graham

Hi Simon,

The inertia matrix cannot be the function of time (I assume the length is changing with time). You can probably replace the rigid body frame with a prismatic joint whose length can be changed (see attached), or use the “Translational Spring Damper actuator” component (although this technique requires substantial amount of work).

Thanks,

Graham

Mi Mostafa,

1-      Playback mode is just for visualization purposes. If you would like to change the position of the platform, you can apply a different input signal by changing the input signal values. You can also change the parameters of the multibody components to modify the actuator lengths, and so on.

2-      To connect the model to the outside world, you have some options. MapleSim allows you to generate royalty-free C-code that can be imported into a variety of other programs. For a list of third party tools that we connect to, see the Toolboxes section at http://www.maplesoft.com/products/maplesim/index.aspx

 

Thanks,

 

Graham

Hi James,

 

 

What's happening is that MapleSim is not finding any core DAEs that it needs to integrate (what is shown by default in the template).  If you look at the definitions set in your equations, you should see the pieces you were expecting. Take a look at the MapleSim help page: GetEquations.

 

I hope that helps!

 

-Graham

Hi there,

 

  Once you save your model and close it, all of your model attachments and relevant files will be stored within the msim file. While you are working on the model, MapleSim will use your Temp folder as a working directory. I recommend that you save and close your model before switching workstations, but if you'd prefer to keep things open, you can look into creating a Hardlink to your temp folder that links to dropbox. As it stands now, MapleSim doesn't allow you to define a custom working directory.

 

Thanks,

 

Graham

Hi Onder,

 

  Unfortunately, when it comes to creating Modelica custom components, we don't offer any specific form of training or examples. We hope to do this in the future, but now I can only encourage you to do your own research into the Modelica environment, and using their code to create custom components.

 

Good luck! This might seem like some additional work, but it will surely give you great capbility within MapleSim to create very specialized components.

 

-Graham

Hi there,

 

  Using the custom component template, you can create components with vectors, but not matrices. If you're looking to include both, you can still do this, but you will have to use a Modelica Custom Component.

 

Thanks,

 

Graham

Hi Ron,

 

  If you're okay with fixed steps, you can use GetCompiledProc and run that within Maple so the compiling will happen just once. Also, as an FYI, it's not necessary to define a DynamicSystems object to create a custom componenet.

 

Thanks,

Graham

Hi Brunoleos,

 

   The Planetary Rover model will be posted to the Maple Application Center in the near future, and you can take a look at the ground/wheel interaction in this model. The "ground pattern" is a CAD geometry that serves for visualization only. The interaction itself is modeled through signal components which draw from STL information that has been inputted as a lookup table. Currently, it's not possible to model the ground/wheel interaction directly through CAD geometry or built in ground pattern components. 

 

  Thanks,

Graham

Hi Andras,

   A custom component can consist of a list of ODEs and algebraic equations (together, DAEs). You can’t include programmatic code that will execute at runtime (at t = 0 or every delta-t), but you can certainly use programmatic code to generate your equations, then construct the custom component. One tip is that you can use piecewise functions in your equations, so you can effectively switch between modes of operation using piecewise. If you’d like some help, please contact Applications Engineering at ApplicationsEngineering@maplesoft.com and we can get you some examples.

Thanks,

Graham

Hi Christian,

 

Currently we don't that library in MapleSim. Support will be coming in MapleSim 6, however.

 

-Graham

Here's an example of how you might do this in Maple:

N := 5; M := 3;

mySubs := [seq(s_P||i(t) = s[i](t), i = 1..N), seq(theta_R||i(t) = theta[i](t), i = 1..M)];

subs(mySubs, myEquations);

 

You could just put this in the multibody template and set N and M to your own values.

 

-Graham

Hi there,

 It's not directly possible to do this, however, using Maple, you can compile the model to C code (using GetCompiledProc), then simulate the model without having to recompile for subsequent runs. I hope that helps a bit!

 

-Graham

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