At Sensors Expo 2019, Lou Thaddeo, the Director of Business Development for Thales Visionix Inc. discusses how Visionix’s newest NavChip Series 3 inertial measurement unit (IMU) plays a critical role in helmet mounted displays for pilot head tracking and other applications. The 6-axis (3-axis accelerometer and 3-axis gyroscope) IMU implements enhanced performance over NavChip Series 2 devices. The microelectromechanical systems (MEMS)-based high performance IMU is offered in two classes. Class A has a 5-degree/hour max drift and Class B has 10-degree/hour max drift for the bias in-run stability. Another enhanced feature is an update rate of 1000 Hz AHRS (attitude and heading reference system) output and other minor improvements based on customer inputs about the previous series. The very low drift IMU has a full-scale acceleration range of +/- 16 g and a full-scale angular rate of 2,000 degrees/sec.

An example of how the Series 3 IMU will be used is the HObiT (Hybrid Optical-Intertial Tracking) System mounted on the back of a Scorpion helmet mounted display system. The Series 3 provides the inertial part of a head tracking system.

Other applications displayed at Sensors Expo include the NavShoe, an engineering protype of a pedometry-based tracking system and the IS-1500 InertiaCam, a visual inertial tracking system suitable for GPS-denied environments. The IS-1500 with its embedded Series 3 IMU is ideal for augmented reality and robotic navigation applications.

The Series 3 IMU’s small (12.5 x 24.4 x 6.1 mm) package with snap-fit connector for easy attachment to electronic printed circuit boards makes it ideal for in a variety of commercial applications that require inertial measurements.