• Mikael Svenstrup
Helicopter Aided Mapping Of Crops (HAMOC) is a project, which aims at making a small scale electric helicopter able to obtain imagery of a crop field. This report considers the first steps towards this, by the use a Corona 120 electric helicopter. The project goal is to make the helicopter hover autonomously in the laboratory. The project has been divided into four main parts; hardware implementation, modelling, state estimation, and control development. Regarding hardware, it has been chosen to control the helicopter by an external computer, and use an external power supply. The computer is interfaced to a servoboard on the helicopter by a serial connection. An existing helicopter model has been described, adapted to the Corona 120 helicopter, and the parameters have been determined. The 12 rigid body states of the helicopter have been estimated using image processing of camera data and an inertial measurement unit (IMU), which as fused in an extended Kalman filter. Four decoupled PID controllers have been developed to control the helicopter (for the z, y and x axes, and for the yaw angle, respectively). Hereafter, more advanced controllers have been researched. The hardware works as expected, and it is possible to control the helicopter from the external computer. The developed controllers are able to control the nonlinear model in a simulation. At the end of the project period, autonomous control of the altitude of the real helicopter has been reached, and preliminary tests of a lateral controller have also been done. A helicopter crash has damaged some of the hardware, and has thus prevented further tests of the horizontal controllers, but it is expected that autonomous hover is close to be obtained. It is believed that the developed subsystems form a solid basis for further work on the project.
Publication date2007
Publishing institutionAAU
ID: 9931548