How to resolve : "Not enough input derivatives were provided for one or more Simulink-PS Converter blocks associated with the highlighted Solver Configuration block, for the solver chosen." ?

Hello,

I'm trying to use a DC motor (combined with a gear box) to make my solid (which I imported from Solidworks) rotate, and to monitor its torque and angular speed. Here's a screenshot of my workspace :

Every time I hit run, it answered

"Not enough input derivatives were provided for one or more Simulink-PS Converter blocks associated with the highlighted Solver Configuration block, for the solver chosen. Implicit solvers (ode23t, ode15s, and ode14x) typically require fewer input derivatives than explicit solvers, and local solvers never require any. You can provide more input derivatives by selecting different options (including turning input filtering on or increasing the number of user-provided input derivatives) on the Input Handling tab of Simulink-PS Converter blocks linked below:

...'matlabprojet3/Revolute - Rotational Interface/Simulink-PS Converter' (1 required, 0 provided)"

So I tried several solutions including changing the solver to one of those advised, setting the Revolute-Rotational interface to "filter input", or setting the solver to "local solver". All of these changes lead to this other message when I tried to run :

"Initial conditions solve failed to converge. ...Nonlinear solver to advance time one step failed to converge due to Linear Algebra error. Failed to solve using iteration matrix.

......Equations of one or more components may be dependent or inconsistent. This can cause problems in transient initialization. Here is the set of components involved: 'matlabprojet3/Ideal Torque Sensor' Equation location is: 'C:/Program Files/MATLAB/R2013a/toolbox/physmod/simscape/library/m/+foundation/+mechanical/+sensors/torque.ssc' (line 37)

'matlabprojet3/Revolute - Rotational Interface/Angular Velocity Source' Equation location is: 'C:/Program Files/MATLAB/R2013a/toolbox/physmod/simscape/library/m/+foundation/+mechanical/+sources/angular_velocity.ssc' (line 37)

'matlabprojet3/Revolute - Rotational Interface/Torque Sensor' Equation location is: 'C:/Program Files/MATLAB/R2013a/toolbox/physmod/simscape/library/m/+foundation/+mechanical/+sensors/torque.ssc' (line 37)"

I'm not really used to using Matlab but I searched around it and on the internet and didn't find how to fix this. Could you please tell me how to get this to work and to get some results in the scopes ?

Thanks in advance,

Adrien.

Answer 1

[Sebastian Castro]

Not sure if this is the only problem leading to the error, but looks like the R and F ports of the Revolute-Rotational interface block are connected to the same node (the "C" side of the motion sensor).

Could you try making sure that the R port of this interface block is hooked up to the R port of the motion sensor?

Also, what solver are you using for your model? If you look near the top of your error, the physical modeling recommended solvers are listed: "Implicit solvers (ode23t, ode15s, and ode14x) typically require fewer input derivatives than explicit solvers." If you haven't already, try changing to ode23t, for instance, and see what happens.

Let me know how this goes.

- Sebastian

[ahmed abd alaziz]

hey/ sebastian i have the last same problem which is : Nonlinear solver to advance time one step failed to converge due to Linear Algebra error. Failed to solve using iteration matrix.

...Here is the set of components with unconverged equations:

'DCmotorModel/Rotational Pneumatic- Mechanical Converter' Equation location is: 'C:/Program Files/MATLAB/R2013a/toolbox/physmod/simscape/library/m/+foundation/+pneumatic/+elements/rotational_converter.ssc' (line 99)

'DCmotorModel/Rotational Pneumatic- Mechanical Converter' Equation location is: 'C:/Program Files/MATLAB/R2013a/toolbox/physmod/simscape/library/m/+foundation/+pneumatic/+elements/rotational_converter.ssc' (line 99)

could you tell me how to fix this error??