An Embedded System of Automatical Timber Classification by Rigidity Detection

On the basis of establishing a mathematical model, the real-time test of elastic ratio of timber sticks is transformed to the test of deflection under certain loads and ARM embedded system is used to operate a pneumatic device to test the elastic ratio of stick, and control air cylinder to classify sticks according to rigidity automatically and then put them in respective place. The system consists of two levels. The manage level uses PC; the control level uses 32 bits ARM7 MPU. They communicate with RS232 serial communication protocol. Several anti-interference methods have been implemented to ensure the system´s reliability and consistency. The system has such functions as automatically feeding, realtime loading and testing, classification, counting, printing testing data, sorting statistic results, alarm on error. The system accomplishes classification of sticks automatically, replacing manual work, which has been applied in a factory. Both the efficiency and precision have remarkable enhancement.