Practical creep and hysteresis error compensation method for load cell

In order to apply the digital compensation technology to a practical use, it is requested to development a method which is as simple as possible for a learning procedure in the production process and calculation procedure in CPU. The long time learning procedure has cause to raise the production cost and the complicated calculation procedure has cause to impose a too heavy load to the CPU running many other real time operations. As to a hysteresis error compensation, we have already presented a method which applied a unique compensation function composed by plural different functions in 2002. However, in a specified load cell, we found to be able to simulate the hysteresis error curves enough accurately by each single 2-order or 3-order functions to the increasing load and the decreasing load. Then, we have developed an easy method about learning process and compensation calculation for the above load cell on the basis of development in 2002. On the other hand, the output signal of load cell also includes a creep error and it prevents us from evaluating accurately the effect of new hysteresis error compensation. This time, we also showed how to put the creep compensation technology developed before for practical use and tested the newly developed easy and simple hysteresis error compensation method to a sample load cell made from SUS material applying this creep compensation method at the same time and evaluated the hysteresis error compensation effect. As a result of the above test operations, we could make sure that our compensation method for hysteresis error is effective enough for practical use.