IMU integrates three-axis acceleration sensor and gyroscope for VR/AR
Realistic, immersive experience for virtual reality (VR) and augmented reality (AR) are provided by the inertial measurement unit (IMU) introduced by Bosch Sensortec at electronica China this week.
The BMI085 is a six-axis IMU which integrates a three-axis, 16-bit MEMS acceleration sensor and a three-axis, 16-bit MEMS gyroscope in a single 3.0 x 4.5 x 0.95mm³ package.
In addition to VR and AR applications, the BMI085 IMU is also suitable for navigation, body/human motion tracking and high-end gaming. The compact MEMS sensor package combines a low-drift gyroscope with a low-noise accelerometer to significantly reduce the unpleasant motion sickness effect, says Bosch Sensortec. Its precise, instantaneous detection of head movements reduces time-lag to an almost imperceptible minimum, claims Bosch, for a more authentic and immersive VR and AR experience that enables headset users to engage their virtual environments for longer periods without requiring frequent breaks. Users can enjoy a realistic VR/AR experience, without the negative physical effects, says Bosch Sensortec CEO, Stefan Finkbeiner.
The low latency of the BMI085 enables headset manufacturers to eliminate image drifts and deliver a true real-life experience, says the company. The IMU delivers a low motion-to-photon latency of less than three milliseconds and achieves near perfect stability in environments with high temperature fluctuations as often encountered in continuous head-mounted displays (HMDs) or AR headsets. This further improves accuracy, which is critical in today’s lightning fast high-definition AR/VR applications, says Bosch Sensortec.
The sensor’s accelerometer delivers a low temperature co-efficient offset (TCO) of typically less than 0.2mg/k and temperature co-efficient sensitivity (TCS) of only 0.002 per cent/k. Bias instability of the gyroscope is typically below two degree/h.
The BMI085’s gyroscope features a closed-loop ADC mechanism, which ensures low drift characteristics even in high-fluctuation temperature environments. The accelerometer achieves a noise density of under 120-micro g/√Hz. The IMU’s accuracy is further boosted by data synchronisation of the accelerometer and gyroscope.
The BMI085 is pin-to-pin compatible with Bosch’s BMI055 IMU, for ease of design migration. The BMI085 will be available via distributors at the end of May 2018.
