eng-controls-sim

Prerequisites

Matlab
Simulink

Installation

mkdir rloopsim
cd rloopsim
git clone https://github.com/rLoopTeam/eng-controls-sim.git

Run Trajectory Simulation

Generates plots and csv files for trajectory scenarios under the specified simulation parameters.

1. Configure simulation parameters in 'simParameters.m'

   create new case or change 'caseno' to desired case to use its corresponding simulation parameters

   e.g.,

   caseno = 48
   
   ...
   
       case 048    % Full test track case at 1.0g with skis 10mm hover height without instantaneous braking
           mpod = 441.;                 % Total pod mass (kg)
           dt = 0.01;                   % time step (s)
           xf = 1250;                   % Target distance (m)
           xdotf = 0.01;                % Target final velocity at xf (m/s)
           gForce_pusher = 1.0;         % Pusher acceleration (g's)
           deltax_pusher_max = 487.68;  % Max push distance (max: 487.68m or 1600ft) (m)
           deltat_pusher = 10;          % Desired max push distance (max: 487.68m or 1600ft) (m)
           deltat_cruising = 5.2;         % Cruising time between pusher and deceleration phase (minimum 2s required) (s)
           brakegapNom = 2.5;           % Nominal brake gap during controlled braking phase (mm)
           deltax_dangerzone = 50;      % Distance between final target and end of track (DANGER ZONE!!!) (m)
           z_nom = 0.010;               % Nominal hover height (m) based on pod mass and 8 hover engines
           ski_option = false;          % Enables/disables addition of skis
           instant_braking = false;      % true = brakes reach nominal brakegap instantaneously
           PIDcontroller = false;       % true = brakes actuators use PID controller to adjust trajectory
   
           %%%% Pressure %%%%
           Ppsi = 0.4;              % Atmospheric air pressure inside SpaceX test tube (Psi)
           
           % Using ideal gas law, P = rho*R*T, solve for rho 
           P = 6894.76*Ppsi;           % Atmospheric air pressure inside SpaceX test tube (Pa)
           R = 287.05;                 % Ideal gas constant (J/(kg*K))
           T = 293.15;                 % Atmospheric air temperature inside SpaceX test tube (K)
           rho = P/(R*T);              % Air density inside SpaceX test tube(kg/m^3)
   
           %%%% Relative Error (eta is positive for under-estimated case; negative for over-estimated case)%%%%
           eta_aerodrag = 0.0;        % Estimated aerodynamic drag relative error
           eta_hoverdrag = 0.0;       % Estimated hover-engine drag relative error
           eta_brakedrag = 0.0;       % Estimated brake drag relative error
           eta_skidrag = 0.0;         % Estimated ski drag relative error
   

2. Run 'Trajectory.m' to generate scenario

Run Trajectory Simulation (with controlled braking)

Simulates response dynamics of controlled braking algorithm under specified disturbances and/or relative error estimations in drag forces

1. Generate Simulation Parameters and Setpoint Tables (Velocity & Position) from running 'simParameters.m' and 'Trajectory.m'

2. Run 'GainScheduledPIDTuner.m' to generate Theoretical Gains linearized by breakpoint table

3. Run 'GainScheduledPIDBrakingSystem.mdl' to visualize response dynamics

4. Open 'Scope' to see response dynamics