This thesis project is about quality assurance of nailed pallet, which is suggesting and evaluating a solution able to detect unknocked nails in a pallet at the company AvenPallen.

The company AvenPallen is responsible for the production of different kinds of wood products, and these products are usually nailed in a robot cell. Due to variation in the wood, like unevenness of the density and tilt and twist of the boards, the nail may not be completely driven into the wood. This can results in an uneven smoothness of the pallet surface, and the production is unable to meet the requirements of customers and cause waste. To solve this problem the company AvenPallen manages to seek some systems to achieve quality assurance process in nails.

The project has suggested four possible systems for detecting unknocked nails in a pallet. The suggested systems are mechanical inspection system, optical inspection system, vision technique system and 3D laser scanning system. By consider the situation of the company AvenPallen, there has been two improved system which are: optical inspection system and shadow inspection system. The optical inspection system uses the optical sensor to measure the height of nail to guarantee the quality of pallets. The shadow inspection system uses a CCD camera and a light to get some figures to measure the height of nails to ensure the quality of pallets. The two improved systems have been evaluated through tests. A suggestion of a possible analysis system is also included in the report.

The report will give the analysis and result for the evaluation experiments and show that the shadow inspection system is a suitable inspection system with the possibility to analyse the measured data.