Design of all the new tools and implements is based on careful experiments with electronic instruments. First, a human' guinea pig' is tested using a regular tool. Measurements are taken of the amount of work done, and the buildup of heat in the body. Twisted joints and stretched muscles can not perform. as well, it has been found, as joints and muscles in their normal positions. The same person is then tested again, using a tool designed according to the suggestions made my Dr. Tichaner. All these tests have shown the great improvement of the new designs over the old. One of the electronic instruments used by Dr. Tichauer, makes visible through electrical signals the work done by human muscle. Another machine measures any dangerous features of tools, thus proving information upon which to base a new design. One conclusion of tests made with this machine is that a tripod stepladder is more stable and safer to use than one with four legs. This work has attached the attention of efficiency experts and time-and-motion-study engineers, but its value goes far beyond that. Dr. Tiehauer's first thought is for the health of the tool user. With the repeated use of the same tool all day long on production lines and in other jobs, even light manual work can put heavy stress on one small area of the body. In time, such stress can cause a disabling disease. Furthermore, muscle fatigue is a serious safety hazard. Efficiency is the by-product of comfort, Dr. Tichauer believes, and his new designs for traditional tools have proved his point. What are involved in the design of a new tool according to the passage?