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I have the situation from the following drawing:

enter image description here

It represents a model for measuring the torque of a generator. There is an arm connected to stator and, the other end of the arm to a bending type load cell. I want to model this system and have as an input the torque of the generator rotor and as output the torque that reaches the load cell. I want to model somehow how is the transfer of energy from the rotor to the load cell. The load cell type is Hottinger Z6FC3. The system is connected like in the figure below.

enter image description here

I am new at this and don't know much mechanics. I don't know how to write the motion equations for the two bodies and connect them.

Razvan
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1 Answers1

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You need to apply Newton's second law that states:

Second law: The vector sum of the forces F on an object is equal to the mass m of that object multiplied by the acceleration vector a of the object: F = ma.

In your case, you need to replace force by torque, mass by inertia and acceleration by angular acceleration. Given that the torque provided by the rotational springs is the spring stiffness x the relative angle and that the torque provided by the rotational dampers is (in the first instance) the damping coefficient x the relative angular velocity, you get:

$ T = (J_s + J_a) \ddot{\theta_r} + C_m (\dot{\theta_r} - \dot{\theta_s}) + K_m (\theta_r - \theta_s)$

$ J_{Gs} \ddot{\theta_s} + C_{Gs} \dot{\theta_s} + K_{Gs} \theta_s = C_m (\dot{\theta_r} - \dot{\theta_s}) + K_m (\theta_r - \theta_s)$

where $\theta_r$ and $\theta_s$ are the rotational displacements of the rotor and the stator, respectively.

am304
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