UAV-Simulator Project

A stall demo footage:

mid_oct_stall_demo.mp4

Overview

This project is a fun and educational initiative aimed at simulating small scale aircraft dynamics and control. The project leverages various libraries for 3D rendering and mathematical operations to model and visualize aircraft behavior based on state variables and control inputs.

Current Status

Active Development: The project is currently being actively developed. While a recent data loss occurred, I've managed to recover a primitive version of the simulator, which will serve as a foundation for ongoing improvements. Stay tuned for regular updates as we enhance features and functionalities!

Recent Changelog:

28th October 2024

• Runga-Kutta 4: Changed the simplistic solver to RK4 based integrator for much better estimation of state parameters.

20th October 2024

• Modularization: Refactored the forces and moments function from a monolithic structure to a more modular design for improved clarity and maintainability.
• Dynamics Function: Transitioned the dynamics function to a modular structure, facilitating easier updates and modifications.
• Animation Cleanup: Cleaned up the animation function by introducing an update function that manages all necessary updates to the simulation before rendering.
• Coordinate Frame: Added a body frame coordinate system that is always visible and coincident with the aircraft, providing a consistent reference for the simulation.

16th October 2024

• Visualisation Method: Changed the simple vertex/face based rendering to surface mesh based one allowing for import of any 3d model into the simulator.
• Changes to Aircraft Class: Removed multiple depricated functionds and added new ones to help with the new render system.

Features

• Aircraft Dynamics: Models the physical characteristics and flight dynamics of an aircraft.
• State Tracking: Tracks various state variables including position, velocity, and orientation.
• Control Inputs: Handles different control inputs such as throttle, aileron, elevator, and rudder.
• 3D Rendering: Uses Easy3D for rendering and visualizing aircraft dynamics in a 3D environment.
• Graphing: Includes basic functionality for plotting and analyzing aircraft state data.

Dependencies

This project relies on the following libraries:

• Eigen: For linear algebra operations.
• matplotlibcpp: A C++ wrapper for Matplotlib to plot graphs.
• Easy3D: For 3D visualization and rendering.

Building the Project [NOT RECOMMENDED FOR NOW]

To build and run this project, follow these steps:

1. Clone the Repository:

   git clone https://github.com/msk2000/UAV-Simulator.git
   cd aircraft-simulation

2. Install Dependencies: Ensure you have the necessary libraries installed. You may need to follow the installation instructions for Eigen, matplotlibcpp, and Easy3D.

3. Compile the Code:

   g++ -o aircraft_simulation main.cpp -I/path/to/eigen -I/path/to/matplotlibcpp -I/path/to/easy3d -lX11 -lGL -lGLU

4. Run the Simulation:

   ./aircraft_simulation

Known Issues

• Data Loss: Recent updates to the project have been lost. The current code is a recovery of an older, less developed version.
• Incomplete Features: The project is still under development, and some features are not fully implemented or tested.

Future Work

• Feature Completion: Completing and improving the simulation features.
• Enhanced Rendering: Adding more detailed and interactive 3D visualizations.
• Improved Data Handling: Recovering and integrating the latest data to enhance the simulation accuracy.
• Incorporate QT libraries: This is intended to replace the current dependency on matplotlib.

Class Members for Aircraft Simulation

The following table details the key parameters used in the simulation. These parameters represent the physical properties, control inputs, and initial conditions of the aircraft. This table will help you understand both the class members and the data.txt file that the simulator uses to load a given UAV configuration.

#	Parameter	Description
1	mass	Aircraft mass in kilograms.
2	Jx	Moment of inertia about the x-axis (roll) in kg·m².
3	Jy	Moment of inertia about the y-axis (pitch) in kg·m².
4	Jz	Moment of inertia about the z-axis (yaw) in kg·m².
5	Jxz	Product of inertia for coupling between the x and z axes.
6	S_wing	Wing surface area in square meters.
7	b	Wingspan in meters.
8	c	Mean aerodynamic chord length in meters.
9	e	Oswald efficiency factor.
10	g	Gravitational acceleration constant (9.81 m/s²).
11	rho	Air density in kg/m³.
12	k_motor	Motor constant representing the relationship between motor speed and thrust.
13	S_prop	Propeller surface area in square meters.
14	k_T_P	Motor torque constant (to be defined based on propeller efficiency).
15	k_Omega	Propeller rotational speed constant (to be defined based on efficiency).
16	C_L_0	Zero-lift coefficient of lift.
17	C_L_alpha	Lift curve slope, relating angle of attack to lift.
18	C_L_q	Lift coefficient due to pitch rate.
19	C_L_delta_e	Lift coefficient due to elevator deflection.
20	C_D_0	Zero-lift drag coefficient (parasitic drag).
21	C_D_alpha	Drag coefficient as a function of angle of attack.
22	C_D_p	Drag coefficient due to roll rate.
23	C_D_q	Drag coefficient due to pitch rate.
24	C_D_delta_e	Drag coefficient due to elevator deflection.
25	C_m_0	Zero-lift moment coefficient.
26	C_m_alpha	Moment coefficient due to angle of attack.
27	C_m_q	Moment coefficient due to pitch rate.
28	C_m_delta_e	Moment coefficient due to elevator deflection.
29	C_Y_0	Zero-sideslip yaw force coefficient.
30	C_Y_beta	Yaw force coefficient due to sideslip angle (lateral stability).
31	C_Y_p	Yaw force coefficient due to roll rate.
32	C_Y_r	Yaw force coefficient due to yaw rate.
33	C_Y_delta_a	Yaw force coefficient due to aileron deflection.
34	C_Y_delta_r	Yaw force coefficient due to rudder deflection.
35	C_ell_0	Roll moment coefficient at zero sidesli
36	C_ell_beta	Roll moment coefficient due to sideslip angle.
37	C_ell_p	Roll moment coefficient due to roll rate.
38	C_ell_r	Roll moment coefficient due to yaw rate.
39	C_ell_delta_a	Roll moment coefficient due to aileron deflection.
40	C_ell_delta_r	Roll moment coefficient due to rudder deflection.
41	C_n_0	Zero-yaw moment coefficient.
42	C_n_beta	Yaw moment coefficient due to sideslip angle (lateral stability).
43	C_n_p	Yaw moment coefficient due to roll rate.
44	C_n_r	Yaw moment coefficient due to yaw rate.
45	C_n_delta_a	Yaw moment coefficient due to aileron deflection.
46	C_n_delta_r	Yaw moment coefficient due to rudder deflection.
47	C_prop	Propeller thrust coefficient.
48	M	Transition Rate used for Stall Characteristic modelling
49	epsilon	Downwash gradient coefficient.
50	alpha0	Zero-lift angle of attack.
51	pn0	Initial position in the North direction (in meters).
52	pe0	Initial position in the East direction (in meters).
53	pd0	Initial position in the Down direction (negative altitude, in meters).
54	u0	Initial velocity along the body x-axis (forward velocity).
55	v0	Initial velocity along the body y-axis (side-slip velocity).
56	w0	Initial velocity along the body z-axis (vertical velocity).
57	phi0	Initial roll angle (in radians).
58	theta0	Initial pitch angle (in radians).
59	psi0	Initial yaw angle (in radians).
60	p0	Initial roll rate (body frame).
61	q0	Initial pitch rate (body frame).
62	r0	Initial yaw rate (body frame).
63	delta_t	Throttle input (ranging from 0 to 1).
64	delta_a	Aileron deflection (control surface input for roll control).
65	delta_e	Elevator deflection (control surface input for pitch control).
66	delta_r	Rudder deflection (control surface input for yaw control).
67	delta_t_max	Maximum throttle setting.
68	delta_t_min	Minimum throttle setting.
69	delta_a_max	Maximum aileron deflection.
70	delta_a_min	Minimum aileron deflection.
71	delta_e_max	Maximum elevator deflection.
72	delta_e_min	Minimum elevator deflection.
73	delta_r_max	Maximum rudder deflection.
74	delta_r_min	Minimum rudder deflection.

Usage

Each of these parameters is used to model the dynamics of the aircraft in simulation, ensuring that the response to control inputs and environmental factors is accurate. For more details, refer to the implementation in simulation.h. Additional details about how to obtain these parameters for a given UAV will be provided in the future.

Contributing

Contributions to the project are welcome. If you'd like to help improve the project, please fork the repository and submit a pull request with your changes.