Getting it right

This particularly applies to assembling products from parts. Curiously, or perhaps not so curiously, there is found to be a bigger problem with assembling products with a small number of parts or placing a few items into boxes, than putting together complicated pieces of machinery. A complex product requires and normally receives careful attention, but something simple, which is put together without conscious thought passing through any thinking part of the human brain is liable to be done wrong when attention wanders. Since some tasks are still easier and less costly to accomplish using human handling than programmed robots it is necessary to ensure that the humans do things right, regardless of whether they are consciously thinking about what they are doing or not. The Challenge Our challenge this month is to come up with a method of monitoring human assembling, and without being excessively intrusive or draconian, advise workers if they have made a mistake, and help them put it right. Video surveillance and vision system analysis is one possible way of doing things, but many workers would regard it as excessively intrusive. It would also be likely to be very expensive, requiring several cameras pointing from different angles and a very powerful computing engine to process all the frame data in real time. Interactive 3D game technologies offer cheaper possibilities, although the patented technology solution that we offer below comes from an entirely different technology arena where it is already very well established. See if you can come up with anything better. Solution The best solution we have come across uses is called "assyControl" and uses ultrasonic tracking of operator hands. It is the property of the German company, Otto Kind, maker of factory, office and shop fittings for more than 100 years. Its origin, however, according to Frank Honisch, managing director of developers Soft2Tec, "Comes of out of the medical field for checking human joint movements", which their associated company, Science & Motion Sports has developed into the very successful "SAM PuttLab" system, which analyses the 28 most important parameters of putting strokes in golf, and displays the results in a graphic format to help players improve their performance. The way it works in the manufacturing assembly environment is to have operators wear sender units called "markers" which indicate the positions of their middle fingers to a 3D tracking system overhead. Accurate to 0.1mm, the system is connected to a control system that optionally confirms with light or sound signals, while incorrect movements are reported, optically or acoustically, and are shown to the user on a PC monitor. Uncritical errors can be corrected while critical errors lead to the rejection of the assembled parts. The employee confirms the report by touch screen monitor and continues work. The system is highly portable, and can be commissioned anywhere, and then taken down and packed up and used somewhere else. Honisch demonstrated both the assyControl and PuttLab systems to us at the Hannover Fair in April.