This report has suggested four possible systems for detecting un-knocked nails in each pallet in the production process. The suggested systems are mechanical inspection system, optical inspection system, vision technique system and 3D laser scanning system. By considering the situation of the company AvenPallen, there has been two improved systems which are: optical inspection system and shadow inspection system. The optical inspection system uses the optical sensor to measure the height of nail and the metal inspect sensor to identify nails to guarantee the quality of pallets. The shadow inspection system uses one CCD camera and one light to get some figures to use two different method which are direct measured method and software measured method to measure the height of nails to ensure the quality of pallets. The two improved systems have been evaluated through testing. A suggestion of a possible analysis system is also included in this report.
In the end, this report will show the analysis and results of the evaluation experiments and give the reason why the shadow inspection system is the most suitable inspection system with the possibility to analyze the measured data for the company AvenPallen.
1 Introduction
In this part there will introduce some useful information about the Swedish company AvenPallen, the problem about inspection of this company which they want to improve and try to solve, the scopes of the company and some limitations for the company AvenPallen.
1.1 Background
The company AvenPallen is a Swedish company, the company is responsible for the different types of wood products, and these products are usually in a robot unit. Due to the change of wood, such as the density of each pallet and the tilting and distortion of concave and convex, nail nails cannot be fully into the wood. This problem will cause in the tray on the surface, the smoothness of concave and convex, and production is not possible, in order to meet the requirements of customers, and will cause the cost of waste. In order to solve this problem, the company AvenPallen trying to seek some possible detection system, implement the quality assurance process.
1.2 Problem description
In the process of production, is expected to automatically realize the nail plate quality assurance. Different solutions are possible. On the one hand, the tolerance of the height of the nails must be no greater than 1 mm, this is a relatively small testing data, the need for very high sensitivity of the system. Each plate on the plate, on the other hand, also have from (-1) mm tolerance in the height of 3 mm, it also increases the complexity of the system design. This report attempts to keep key suggest some possible censorship and evaluate different solutions, automatic pallet nails quality assurance AvenPallen help company solve the problem of checking in the process of production.
1.3 Scope
The purpose of this report is to suggest some possible detection system and evaluation system, to detect not knock nail on the wooden pallets. Requirement is to ensure that the tolerances of the height of the nail is less than 1 mm, but there are also some limitations, the tolerance (only 1 mm) were too small to be measured for each pallet and with the allowable tolerance (-1) mm to 3 mm height, it is hard to find a suitable sensors, to adapt to the height.
2 Methodology
The main idea of this report is to find some possible inspection systems to make sure the quality assurance of the nailing process. There are three methods have been considered first, which are height identify, shadow identify and figure identify. In order to get some possible inspection systems, there must be a lot of inspection reference to be studied which may be related to vision technique, infrared sensor, 3D laser scanning and some others.
For the height identify, the manual measurement and infrared inspection system have been considered. However the manual measurement has a low efficiency and accuracy, so the mechanical inspection system can replace the manual measurement system. When talked to the supervisor Anna, it is easy to find the infrared inspection system is hard to achieve. Because the infrared light is harmful to people’s health and it is really expensive light and for a protective cover. Thus, the optical light can be considered to instead of the infrared light, which is cheaper than infrared light and for this system does not need to pay for the protective cover from infrared light. So the optical inspection system is much cheaper and healthier. MATLAB公司木板钉钉的质量保证设计(2):http://www.751com.cn/yingyu/lunwen_15346.html