The load cell had a fairly simple start, with single measurements of compression or tension being the only options. As technology and industry has continued to evolve it has produced requirements to be able to measure very large forces in multiple directions, including torsional forces, by increasingly smaller devices to increasing levels of accuracy. Therefore it is perhaps more important than ever to be able to match the task at hand to the appropriate force measurement device.
The range of applications routinely using a load cell in order to provide accurate and reliable force readings is growing by the day. Older systems are being phased out and modern measurement systems are being introduced. One of the benefits of modern load cells is that they can be used in a flexible manner. They can provide a direct force measurement to a hand held gauge, or they can feed their measurements into an automated monitoring system that can have triggers set, or be directly linked into a longer process within a manufacturing plant to provide active feedback that particular processes may have been completed and so the next phase can start.
Miniature load cells are gradually decreasing in size, but they are either maintaining or exceeding measurement capabilities of their predecessors. These miniature, and now also subminiature, force measurement devices are able to measure high levels of compressive force in a very compact design. The design also provides stability of the device over time so readings are stable and are comparable.
Force measurement does not only incorporate large loads, there are often requirements to measure small loads as well. This can be particularly true in laboratory testing. Here delicate structures may require to be assessed against the application of a very small amount of force, perhaps the touch screen of a phone. In these cases dedicated low force sensors have been developed that have the sensitivity to allow these small forces to be accurately measured.
The manufacturing of items continues to move more and more towards automation. Initially automation was a fairly clunky process that still required a fairly high amount of human monitoring. With the development of increasingly sensitive and robust load cells and also more flexible production methods, there is a decreasing need for humans to be in the loop. One of the reasons for this is that processes can be monitored through the use of tension and compression measurements, which indicate whether a process is being carried out correctly. This could range from the basic stamping out of shapes in a material, to checking the torsional forces being applied to a bottle top. A load cell can provide measurements to an automated monitoring device, which then only alarms when a preset trigger point is reached, which then indicates the requirement for human intervention.
The measurement of forces may seem like something that is pretty basic, but the range of forces and methods of force measurement present in both research and industry today indicate that there is a great deal to be understood in order to ensure the best tool is being used for the job.