Description

The UM7 orientation sensor is a third-generation Attitude and Heading Reference System (AHRS) from Redshift Labs that produce attitude and heading estimates from the triaxial accelerometer, rate gyro, and magnetometer data. Unlike a typical inertial measurement unit (IMU), which only provides raw sensor readings, the UM7 features an onboard microcontroller that combines sensor data using a sophisticated Extended Kalman Filter (EKF) to generate orientation estimates 500 times a second.

Connections for power and TTL serial communication can be made to the UM7 through a polarized five-pin male connector on one side, which mates with an included cable assembly. A pair of six-pin expansion headers on the other side of the board provide additional connectivity options, including an alternative SPI interface and a secondary serial interface that can be connected to an external GPS module. Additional cable assemblies for the expansion headers are not included.

Specifications

• Dimensions: 1.06" x 1.02" x 0.26"
• Weight: 3.5g (.012oz)
• Interface: TTL serial, SPI
• Minimum Operating Voltage: 4V
• Maximum Operating Voltage: 5.5V
• Maximum Logic Voltage: 3.3V (The main UART pins, TX and RX, are 5V-tolerant and can be used directly with 5 V systems that are guaranteed to read 3.3 V as high. The secondary UART and some of the SPI pins are NOT 5V-tolerant.)
• Axes: Pitch (x), Roll (y), and Yaw (z)
• Measurement Range:
  • Gyro: ±2000°/s
  • Accelerometer: ±8 g
  • Magnetometer: ±12 gauss
• Supply Current: 50mA
• Case Enclosure Not Included

Features

• Output data:
  • Attitude and heading (Euler angles)
  • Attitude quaternion
  • magnetometer, accelerometer, gyro data
  • GPS altitude, position, velocity (with optional external GPS)
• 3.3 V TTL serial interface (UART) with baud rates up to 921,600 bps can stream data or provide updates on request
• Transmits data using human-readable NMEA strings (up to 100 Hz broadcast), binary packets for higher efficiency (up to 255 Hz broadcast), or a combination of both
• Flexible communication architecture allows UM7 to transmit any combination of data at individually adjustable rates
• Connects to the Redshift Serial Interface software to allow for real-time plotting of sensor data, logging, device configuration, and magnetometer calibration
• SPI interface available through expansion connector
• Attitude and Heading
  • EKF estimation rate: 500 Hz
  • ±1° typical static pitch/roll accuracy
  • ±3° typical dynamic pitch/roll accuracy
  • ±3° typical static yaw accuracy
  • ±5° typical dynamic yaw accuracy
  • 0.5° angle repeatability
  • <0.01° angular resolution

Product Documentation

• Datasheet
• Redshift Serial Interface software
• Upgrading Firmware Instructions
• UM7 Orientation Sensor Product Page