IMU-P inertial sensing unit

The IMU-P from Inertial Labs is a MEMS inertial measurement unit (IMU) that senses angular rate and acceleration for navigation, stabilization and motion-reference tasks on unmanned aircraft, ground vehicles and marine platforms.

The unit uses MEMS gyroscopes and accelerometers with full temperature calibration of all sensing elements. Output data rates reach 2000 Hz, which gives a flight controller or inertial navigation system fresh measurements for fast control loops. It is also fitted with an embedded Kalman filter that can be extended, so attitude estimation can be handled inside the unit when the host requires it.

The performance figures describe how well the IMU holds its estimate between external position or heading fixes. Gyroscope bias instability is 1 degree per hour and angle random walk is 0.08 degrees per root hour, which determine how slowly heading drifts when GNSS or a magnetometer is not available. Accelerometer bias instability is 5 micrograms, and velocity random walk is 0.015 m/s per root hour, which limit the growth of velocity and tilt error during dead reckoning.

The housing is environmentally sealed to IP67, so the unit can be fitted on exposed parts of an airframe, vehicle or vessel. The maker states that the unit shares mechanical and electrical interfaces with the STIM-300, which allows it to replace that part in an existing design without redesigning the mounting or the connection to the host. The product is free of ITAR controls.

Typical applications named by the maker are antenna and line-of-sight stabilization systems, gimbals and electro-optical and infrared payloads, platform orientation and stabilization, motion reference units and motion control sensors, GPS-aided inertial navigation systems, attitude and heading reference systems, land vehicle navigation and motion analysis, buoy and boat motion monitoring, and UAV and AUV or ROV navigation and control.