A Simple and Convenient Sensor for Measuring Gasoline Engine Speed and Its Application in Flight Control of a Portable Unmanned Helicopter

In this paper, based on a very simple physical principle, a simple and convenient speed sensor for gasoline engine used in a portable unmanned helicopter (PUH) is developed. The sensor has several favorable features appropriate for a PUH control, i.e. small, light, taking little space, sufficient accurate and handling easy in control operation, especially, easy and low-cost in produce. Moreover, the same principle and structure is also applicable to a general gasoline engine. The experimental results with an actual PUH have sufficiently demonstrated the effectiveness and practicability of the sensor for the application of PUH control.