Linear sensors have been contributing to many industries for over half a century. Since the development of mass applications after the Second World War, sensors are now an essential component in most machines used for production as well as consumer products. Innovation was paramount in the evolution of sensors into highly accurate devices for measuring displacement. Today, a linear position sensor can be found in applications on air, underwater, and underground.
Linear sensors as feedback devices
A linear position sensor, or commonly known as an LVDT, converts the mechanical movement of an object into an electrical signal. The fundamental working principle of a linear position sensor has not changed since its invention. It is known for having contactless technology which makes a linear transducer useful for harsh environments and working conditions. As a feedback device, a linear position sensor delivers high accuracy, repeatability, durability, and robustness.
New developments in linear sensors
Much has changed with the development of linear sensors. Today, engineers experiment with new materials for fabrication, production techniques, and use of micro-electronics to revolutionise linear transducers. The aim here is to produce a device which is not only reliable but still cost-effective. These are the other factors that paved the way for the modernisation of linear transducers.
- Removal of external electronics. When a device consists of external mechanisms, it can be prone to wear and tear. Today LVDTs house microelectronics used in signal conditioning. As such, linear sensors can perform complex functions. Some DC-operated linear sensors have digital output making them directly compatible with computer systems.
- Enhanced performance. Combining micro-electronics with new construction materials create LVDTs with better performance. Modern LVDTs perform ten times better than similar devices from 20 years before. Environmental factors affecting the performance of a sensor are now correctible, thus enhancing the accuracy of the invention.
- Smaller stroke length and smaller size. In the past, linear position sensors or LVDTs were not compatible with applications requiring shorter stroke lengths. Nowadays, this is no longer an issue. New production techniques reduce the size of sensors and allow for the implementation of microprocessors. Application of compact linear sensors is now possible in hydraulics which in the past was impossible.
- New construction materials. Resistance to various environmental conditions used to limit position sensors. New construction materials like chromium and cobalt make sensors more resistant to extreme cold and heat, as well as increasing resistance to corrosive elements. Hermetically sealing sensors also allows for sensor applications in underwater conditions. There are sensors made with nickel-based alloy resistant to microorganisms present in shallow waters.
Today, innovation in technology and manufacturing techniques promises a bright future for sensor technology. Sensors are more robust, reliable, durable, and accurate. Cutting-edge computer and digital technology require the high-performance sensors produced today. Manufacturers offer different options to buyers looking for sensors applicable in various industrial and commercial processes. Because sensors are essential in the internal mechanism of a piece of equipment, manufacturers often offer customization of packaging, performance calibration, and other techniques to match the specifications required for the application.
