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85 lines
2.2 KiB
Markdown
85 lines
2.2 KiB
Markdown
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# SIM_MSD
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SIM\_MSD is a simulator for a mass-spring-damper system.
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The system is described by the equation _mẍ_ + _bẋ_ + _kx_ = _F_, where:
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_m_ is the mass of an object.
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_x_ is the position of the mass.
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_b_ is the damping coefficient.
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_k_ is the spring coefficient.
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_F_ is an external force applied to the mass.
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---
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### Building the Simulation
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In the SIM_MSD directory, execute **trick-CP** to build the simulation executable. When it's complete, you should see:
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```
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=== Simulation make complete ===
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```
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Now **cd** into models/Graphics/ and type **make**. This builds the display client for the simulation.
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### Running the Simulation
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In the SIM_MSD directory:
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```
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% ./S_main_*.exe RUN_test/input.py
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```
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The following windows should appear:
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### Controlling the Simulation
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Click **Start** to begin the simulation.
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Click **Reset** to freeze the simulation and reset the position and velocity to
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their initial conditions.
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Change **Position** and **Velocity** to adjust the initial conditions for those
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attributes.
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Change **Mass**, **Spring Coefficient**, **Damping Coefficient**, and **Applied
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Force** to adjust initial conditions _**and**_ also update the sim in real-time.
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---
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The following inputs can be set in any of the RUN_*/input.py files to change
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the inputs on startup
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### Inputs
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Variable | Type | Units | Default Value
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---------- |-----------|-------|--------------
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dyn.msd.x_0 | double | m | 5.0
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dyn.msd.v_0 | double | m/s | 0.0
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dyn.msd.b | double | N.s/m | 0.5
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dyn.msd.k | double | N/m | 2.0
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dyn.msd.F | double | N | 5.0
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dyn.msd.m | double | kg | 1.0
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---
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Some sample input.py files have been created to demonstrate different
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mass-spring-damper conditions
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### Samples
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Path |Type
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------------------------|----------------------------------------------
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RUN_underdamp/input.py |Underdamped Harmonic Oscillator
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RUN_critdamp/input.py |Critically Damped Harmonic Oscillator
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RUN_overdamp/input.py |Overdamped Harmonic Oscillator
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RUN_nodamp/input.py | Simple Harmonic Oscillator (No Damping Force)
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