System Design of Water Quality Monitoring Robot with Automatic Navigation and Self-test Capability

Abstract

This paper proposes a water quality monitoring system of underwater robot with self-test and diagnosis capability. The system consists of underwater robot, water quality data collection module, self-test and diagnosis module, wireless communication module, and shore-based facility. The measurement results from each sensor of water quality data collection module are transmitted to the built-in micro-processor of the underwater robot. And the self-test and diagnosis module based on DSP connects with the built-in microprocessor through RS232. The self-test and diagnosis module conducts wavelet transform for the sensor information, generating extreme points of the wavelet transform, which are used to detect the abnormal state of the current system. The threshold method is introduced to reduce the influence of the noise. The disturbance of the noise can be alleviated by setting threshold for high frequency parameters of the wavelet transform. The exceptional information was detected by the self-test module and the water quality data information was transmitted to the shore-based facility through the wireless communication module. The shore-based facility can process, analyze and determine the collected information, and then give feedback to the underwater robot. The feasibility of the system design and the rationality of the water quality parameter measurement results were verified by experiments and on-site tests.