| Gear is a kind of important transmission parts, widely used in a lot of machines. Well known, gear has been playing an indispensable role during the development of industry. In the era of industrialization and information today, gear and its related technologies are still the hotspot of our researches. Its precision directly affects the work performance and service life of the whole machine. Recently,there are several kinds of gear measuring equipments, such as coordinate measuring machines, gear inspection centers and so on. However, these equipments are expensive and have strong technology requirements for users and maintainers, consequently they have not yet been widely used. With the rapid development of machine vision technology, the measurement based on machine vision, which have advantages of non-contact, high speed, dynamic range, has been widely popular.A new method for gear measurement based on machine vision is explored in this thesis. The main contents of this paper included hardware configuration and its type selection of the measurement system, overall structure design of the gear vision measurement system, processing and error analysis of the experimental results, etc. Generally speaking, the key research content was consisted of three parts. Firstly, analyzes the process of image acquisition and camera control, chose components such as camera, lens, light source, lighting way and the hardware platform of measurement system was constructed, introduce the overall structure of the software. Secondly, present the application of image processing technology in the gear measurement, including median filtering to filter out noise, image fill, erode, mask process, edge detection, etc. Thirdly, describe the measurement scheme of gear parameters, including geometric parameters such as teeth, modulus, addendum circle radius, tooth root radius, and individual errors such as measurement profile error, pitch accumulated error, etc.Finally, the paper tested with a standard involutes spur gear. In the certain object distance condition, Firstly, use a standard part to calibrate the gear measuring system; Then in the same visual measurement condition, capture gear image, measure gear parameters according to the measurement program designed in the subject. The experimental results show that it is feasible to measure the gear parameters using the machine vision technology. |
