Physics Graduate Student Symposium | High Performance Micro-Sensors for Navigation-Grade MEMS Gyroscope

GPS navigation is commonly used in many applications including defense, autonomous vehicles, and robotics. However, absolute dependence on GPS is unreliable due to its limited reachability and susceptibility to interference. For example, a jammer or even a simple and cheap device can be used to spoof GPS signal. As a result, for navigation of high-end vehicles like that of defense and military, one can’t rely entirely on GPS. To make navigation more secure and reliable, inertial sensors are used for navigation when GPS signal is unavailable. Inertial sensors consist of primarily three accelerometers and three gyroscopes in the three perpendicular axes to measure acceleration (or velocity or position) or rate (or angle) of rotation respectively for navigation. Gyroscopes are used to measure the rotation rate and angle of rotation with high precision. Commercial gyroscopes which are used in commercial flights as well as space missions are very precise in their measurement. However, their large sizes, high costs and power requirements limit their use in many applications.

MEMS or Microelectromechanical systems consists of a range of mechanical structures which can be used for various applications. They have an inherent advantage of low cost (C), weight (W), size (S) and power (P) or low CWSaP. They, however, are limited in performance due to large noise. This is a major hurdle which has been limiting the entry of MEMS inertial sensors in navigation-grade performance applications. Our research is focused on bridging this gap and making an ultra-low noise MEMS gyroscope using the microfabrication technologies.

In this talk, I will talk about the design and fabrication of miniaturized 3D shell resonators for gyroscopes. These resonators have exhibited quality factor as high as 10 million leading to very low noise gyroscope at their small size. The achieved performance matrices would enable the use of MEMS sensors as a navigation-grade gyroscope at a cost lower by several orders of magnitude than the existing commercial gyroscopes. Only this would enable each one of us to own a self-driving car and autonomous robots at our homes!