The Yost Labs 3-Space Sensor™ Data-logging integrates a miniature, high-precision, high-reliability, Attitude and Heading Reference System (AHRS) / Inertial Measurement Unit (IMU) with a micro-SD card storage device and a rechargeable lithium-polymer battery solution into a single low-cost end-use-ready unit. The Attitude and Heading Reference System (AHRS) / Inertial Measurement Unit (IMU) uses triaxial gyroscope, accelerometer, and compass sensors in conjunction with advanced processing and on-board quaternion-based Kalman filtering algorithms to determine orientation relative to an absolute reference in real-time. Orientation can be returned or stored in absolute terms or relative to a designated reference orientation. The proprietary multi-reference vector mode increases accuracy and greatly reduces and compensates for sensor error. The YEI 3-Space Sensor Data-logging system also utilizes a dynamic sensor confidence algorithm that ensures optimal accuracy and precision across a wide range of operating conditions. When attached to a USB 2.0 host, the YEI 3-Space Data-logging unit can enumerate as both a virtual COM port and a USB mass-storage device. The virtual COM port allows access to real-time sensor data and configuration parameters and the mass-storage device allows access to logging & config options and captured sensor data. Versatile commands provide for raw sensor data, normalized sensor data, and filtered absolute and relative orientation outputs in multiple formats including: quaternion, Euler angles (pitch/roll/yaw), rotation matrix, axis angle, two vector(forward/up).