They are machines or major tools necessary to complete a given task. They are items which are essential for the development of any structure from its initial stage till the final stage. They comprise of any appropriate set of tools required to generate the machine.
Redundant and self-monitoring fault detection systems. Redundant or dual systems (doubling up) and self-monitoring fault detection systems are also effective methods to prevent failure of critical safety systems. Selection and installation of these types of complex interactive control measures may require expert or specialist assistance.
Interlock guarding is generally achieved via mechanical or electrical means, but may also include hydraulic or pneumatic control systems. The energy stored in moving parts (momentum) can cause the mechanism of the machinery or equipment to run on for some time after the source of driving energy has been removed.
The idea of a simple machine originated with the Greek philosopher Archimedes, who studied the machines, lever, pulley, and screw, and discovered the principle of mechanical advantage in the lever. Furthermore, the Greek Philosophers defined the classic five simple machines, which were used to roughly calculate the mechanical advantages.