Development of a tilt measurement system based on MEMS sensor and Cortex_M3

　　Tilt measurement system is a device used to measure

　　the tilt angle of the carrier to horizontal plane， which is

　　widely used in attitude measurement fields such as

　　MUAV， robot， motorcar， ship and so on. The

　　accelerometer can be used for the tilt measurement

　　because of its measurement principle. With the

　　development of MEMS technology， the MEMS

　　accelerometer becomes the best choice to design the

　　micro tilt measurement system for its small size， low

　　power， low cost and strong anti-impact force although its

　　measurement accuracy is lower. Recently how to design

　　the micro tilt measurement system with proper chips and

　　how to deduce the measurement error are studied［1-4］。

　　This paper designs a low-cost， small-size and

　　fast-response tilt measurement system. The contribution

　　of this work focuses on two aspects. One is sticking the

　　3-axis MEMS accelerometer on some plane of a

　　hexahedron and compensating for the accelerometer

　　sensitivity drift with temperature by the sensor in the

　　microcontroller， which makes calibration and error easier

　　and less. The next is using a Cortex-M3 microcontroller to

　　process data， which makes the power consumption and the

　　performance of the system lower and higher.

　　The remainder of this paper is organized as follows. In

　　Section II we will briefly introduce the measuring

　　principle and the structure of the tilt measurement system.

　　In Section III we will describe the hardware design of the

　　system. In Section Č we will show how to compensate

　　the drift error of the accelerometer with the temperature.

　　In Section č we will describe the algorithm realization of

　　the system. In Section Ď experimental results are