Although in many applications robots can offer benefits over humans with the current level of technology available and at today's prices there are still a large number of areas where using a robot is either impossible or impractical. Humans have the following advantages over robots:-
- They have an impressive array of sensors (touch, vision, hearing, pattern recognition)
- They have the ability to learn and make decisions where all of the required data does not exist.
- They can be very flexible and easy to program.
- Low capital investment.
The places that humans are therefore preferred are jobs requiring one or more of these skills.
Final assembly of cars is one area where robots have made little impact. Handling wire harnesses and carpets that are flexible and unpredictable requires sensory capabilities that robots do not currently posses and where the quality of incoming components is not tightly controlled a human operator can scrap bad parts where a robot would attempt to fit it. Where components are supplied to a robot it is essential that the orientation and location of the part is controlled. This adds expense to the process and often for humans parts are simply supplied in bins and can be in any orientation. In order to handle this complex pattern recognition is required.
While on spot welding lines robot cells are normally designed with some redundancy such that if one robot has a fault the others can pick up its work load it is impossible to quickly move a robot onto another job at the other end of a production line. With humans this level of mobility is possible an where tasks are not complex generally they can be taught the task quickly by simply demonstrating it to them and then watching them for a few cycles.
Reprogramming a robot is not yet quite that simple. Often companies that are not in a sound financial decision are put off automation by the capital investment requirement. If cash is in short supply then even though in the long term automation would pay back the investment cannot be made. In this case manual labour is the sensible option.