Research On High-Accuracy Direct-Digital Load Sensor

The paper deals with the designing of direct-digital load sensor which features high accuracy and low sensitivity to noise. A direct analog-to-digital conversion technique is introduced here aiming at the problem that traditional analog-to-digital conversion weighscale has poor performance in long-distance signal transfer and limited capacity for cells. Testing result shows that the sensor's resolution reaches 0.1uV/20mV, with excellent linearity, repeatability and stability.The thesis includes six chapters.Chapter one reviews the main principle and developing trend of the current load sensor, introduces the background knowlege of signal processing and EMC designing, and put forwards the purpuse. significance and main content of this project.Chapter two analyzes the drawbacks of the current load sensor first, and put forwards an innovative direct-digital load cell structure, which combines direct-digital,Σ-Δ , chop and rationmetric technique, and features better performance with lowercost.Chapter three researches on the barriers to the improvement of the sensors' precision. Measures are taken to solve the problems.Chapter four illuminates the EMC design of the high accuracy direct-digital load sensor.Chapter five is about the testing. Both the testing plans and the results are given in details. The design proved to be successful by the testing results.The final chapter draws conclusions from the designing, points out the new ideas of the study, and puts forwards the further study direction.