The system consists of a body, carrying two propellers driven by DC motors, and a massive support. The body has two degrees of freedom. Both body position angles (elevation and azimuth) are influenced by rotation of propellers. The axes of a body rotation are perpendicular. DC motors are driven by power amplifiers using pulse width modulation. Both angles are measured by IRC sensors. Centre of gravity is changed by moving small weight along the main horizontal axis of helicopter by a servomotor. The mathematical model of the helicopter system is a typical MIMO 2x2 system with significant crosscouplings. The electromechanical system can be linearized to a linear sixth-order model when operating near the steady state. As the third input can be considered high speed moving of centre of gravity controlled by servo system.
Range of Experiments
An extensive range of experiments can be carried out with this apparatus:
Multifunction I/O card with eight single ended 14 bit A/D convertor channels, eight 14 bit D/A convertors, 4 encoder inputs, 4 counters/timers, 8 digital TTL inputs and 8 digital TTL outputs.
Two timer channels used for PWM control of helicopter propellers, one timer channel used for the centre of gravity control. Encoder inputs used for IRC and digital I/O for other control signals.
A comprehensive technical manual is provided giving details of the apparatus and full description of model control signals.
Educational Manual provided with the model is an effective tool for using model in teaching process. Manual describes dynamics of the system, many working examples lead the student through experiments from identification to advanced control of the model.
Interface drivers written in C with source code, demonstrational package using PID controllers and drivers for Real-Time Windows Target provided.
Model is designed for control by a standard IBM PC or 100% compatible computer, one free PCI slot required.
Single phase A.C. 220 V / 50 Hz, or 110 V / 60 Hz, 200W supply, with ground.
For satisfactory use of the model a bench area of 1500 x 900 mm is required.
Dimensions and Weights