Starting a quad-rotor helicopter project
I recently graduated from the University of Utah in Computer Engineering. My senior project was a fly-by-wire system for an unmanned helicopter. We used an Align T-Rex 600 ESP helicopter for the project. Designing a stabilization system for this size of helicopter presents many problems. Given that the tips of the blades travel at 350 mph, physical danger was obviously the biggest concern. We successfully implemented our design.
Even though we felt moderate success, we didn’t feel that our system performed as well as it could have. All the supporting hardware and software was implemented but the time needed to calibrate the many features of stabilization caused us to end the project before all features could be utilized. The excessive calibration time is a result of calibrating a 53 inch helicopter during flight. Any changes in the system had to be modified very slowly.
This project gave me a lot of experience with inertial measurement and feedback control. It also gave me a HUGE desire to make something better!
Now I begin a multi-rotor helicopter project. I aim to fix all the faults in the previous design while overcoming many of the short comings of current multi-rotor designs. I will start by designing a 4 rotor system because it is the cheapest. Once I master the quadcopter, I’ll try a hexacopter or an octocopter. I have been impressed by many multicopter designs. Some are:
- HexaKopter by MikroKopter
This design shows a lot of intelligent software engineering. The GPS capabilities of this system are phenomenal. The supporting stabilization system is also very intelligent (see the oscillating coke bottle).
- GRASP Labs Quadrotor
Having the entire room and obstacles marked with position sensors is kind of cheating for autonomous vehicles, but I must admit that these helicopters are amazing! Recovering from severe initial conditions is very impressive.
My goals are to:
- overcome the inheritly slow yaw response of current quad-rotor designs.
- design an extremely aggressive stabilization system.
- find a good balance between size and payload capability.
- make the chassis rigid enough to survive moderately severe crashes.
- create a quadcopter that is ridiculously fun to drive!
My initial design will be very minimal. I will start off with only a basic quad-rotor design controlled by a transmitter/receiver pair. No other communication will be used. I’m designing this to be minimal so that I can focus on the inertial measurements and feedback control. Once these are mastered, I’ll add fluffy features like:
- software ground station
- GPS hold and navigation
- video downlink