Sensing The World

Many people think electronic sensors are newfangled pieces of high-tech equipment, but such sensors have been around since the dawn of electricity when voltage needed to be regulated.

- ONG XIANG HONG

In the broadest definition, a sensor is a device, module, machine, or subsystem whose purpose is to detect events or changes in its environment and send the information to other electronics.

We interact with such sensors on a daily basis. For example, when we press a button to call a lift, a sensor detects when the button is pressed, and so does the necessary commands. When we stand near an automatic door, a sensor (either an IR sensor mounted above the door, or a weight-sensitive sensor in the ground) instructs the electronics to open the door automatically.

And of course, sensors are used everywhere in industry. High-speed optical sensors can detect defects in picked fruits prior to packing. Manufacturing processes that involve toxic or hazardous substances rely on sensors to keep going. Hence, to a significant extent, manufacturing has been in the forefront of incorporating advanced sensor technology.

The current revolution in computer-integrated manufacturing has been enabled by advanced sensor technology. Technological progress has allowed more and more sensors to be manufactured on a microscopic scale as microsensors using MEMS technology. In most cases, a microsensor can achieve a significantly faster measurement time and higher sensitivity compared with macroscopic approaches.