Sometimes GPS doesn't work (due to tunnels or other obstacles, for example). Inertial navigation systems (MEMS gyroscopes) could soon come to the rescue! However, the three-axis gyrometers inside these MEMS sensors will need to be improved substantially to enable accurate navigation without impacting total system costs. Researchers at Politecnico di Milano and CEA-Leti recently developed a tiny (1.3 mm2), vibration-resistant (25 kHz) device that fits the bill.
The new sensor, which is capable of detecting rotation of less than 0.1° per hour with very low noise, is built on ultra-sensitive piezoresistive nanogauges. And the results are more than encouraging. After nine minutes of simulated navigation with sudden (up to 200°/s), random direction changes, the sensor ended up with an angle error of just 0.07°! This is good enough to ensure accurate navigation for durations in the tens of minutes.
Modifications to the MEMS design and improvements to the quality of the vacuum integrated at the sensor level are behind this excellent performance. The sensor offers higher resolution than today's commercially-available gyros, but it is much smaller and will soon be available in a three-axis model. With characteristics like these, the sensor will undoubtedly be of interest to the defense and industrial markets. First and foremost, however, it will respond to the needs of the autonomous vehicle and, later, indoor navigation markets.