measuring force in a spring dashpot model

good morning everyone, i?m quite new of simulink/simscape world, and i've encountered my first issue.. I'm trying to do a simulation on a spring-dashpot model with setted velocity (I tried both step and ramp sources ). when I solve the system and use the translational motion sensor no problems occours while if I connect the system to the force sensor I get the error message reported below. At the end of the day I would like to measure, using simscape, the force necessary to obtain a translation at a constant velocity (I also tried to add a mass with no results). how can I solve the problem?

_An error occurred while running the simulation and the simulation was terminated Caused by: ['trial_3/Solver Configuration']: Initial conditions solve failed to converge. Nonlinear solver: Linear Algebra error. Failed to solve using iteration matrix. The model may not give enough information to make it possible to solve for values of some of its variables. Specific advice is given below.

all components and nodal across variables involved Cannot solve for one or more variables: 'Ideal_Force_Sensor.F' (F) 'Ideal_Force_Sensor.f' (Force) 'Ideal_Translational_Velocity_Source.f' (Force)

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: all components involved 'trial_3/Ideal Force Sensor' Equation locations are: 'C:\Program Files\MATLAB\R2018a\toolbox\physmod\simscape\library\m\+foundation\+mechanical\+sensors\force.ssc' (line 36) 'C:\Program Files\MATLAB\R2018a\toolbox\physmod\simscape\library\m\+foundation\+mechanical\+sensors\force.ssc' (line 37)

'trial_3/Ideal Translational Velocity Source' Equation locations are: 'C:\Program Files\MATLAB\R2018a\toolbox\physmod\simscape\library\m\+foundation\+mechanical\+sources\velocity.ssc' (line 36) 'C:\Program Files\MATLAB\R2018a\toolbox\physmod\simscape\library\m\+foundation\+mechanical\+sources\velocity.ssc' (line 37)___

Answer 1

[Ryan Takatsuka]

The Ideal Force Sensor should be in series with the mechanical system. See the attached example.

[carlo ferro]

great! thank you very much. bye