MEMS Solutions For VR & AR Sensor Expo 2017 San Jose June 28 th 2017
MEMS Sensors & Actuators at ST 2 Motion Environmental Audio Physical change Sense Electro MEMS Mechanical Signal Mechanical Actuate Electric Fluidic Micro-actuators Piezo actuators Micro Mirrors
ST as MEMS Sensor & Actuators Supplier 3 Market-proven Manufacturing Technologies Front-End / Back-End/ Testing & Calibration High Volume Manufacturing Expertise in multi-sensor Integration Leading Smart Functions Integration Key Partnerships in product development
20 Years of MEMS Sensors & Actuators 4 ST Innovations SENSING Accelerometer Gyroscope Inertial module Pressure sensor Microphones UV sensor Humidity sensor GAS & VOC 2000 2005 2008 2010 2012 2013 2014 2015 2017 Fluidic Microactuators ACTUATINGMicro Mirrors Piezo actuators
20 Years of MEMS Sensors & Actuators 5 And Some Iconic Products SENSING 2000 2005 2008 2010 2012 2013 2014 2015 2017 ACTUATING
* Thick Epi-Poly Layer for Microactuators and Accelerometers ** VENice SENSor MEMS Sensors & Actuators 6 ST Key Technologies - Enabling Multiple Applications Sensors Actuators + ThELMA* AMR - MAG Piezo-Electric Electrostatic VENSENS** Bastille Cactus Thermal Electro-magnetic
Changing the MEMS Landscape 7 Strategic Partnerships Piezo Autofocus Ultrasound Ranging MEMS Loudspeaker Micro-mirror Projection
What is a MEMS μmirror Scanner? 8 Tiny reflective mechanical device that swings at a given frequency Applications spanning Visible to Invisible (IR typically) light
Laser Beam Scanning (LBS) 9 Technology Principles and Applications Principles: Light from one/multiple lasers is combined into a single beam Beam is relayed onto MEMS scanning mirror(s) Mirror(s) scan the beam in a raster pattern A projected image is created by modulating the lasers synchronously with the position of the scanned beam Green LD Red LD Blue LD MEMS scanning mirror
Laser Beam Scanning (LBS) 10 Technology Principles and Applications Principles: Light from one/multiple lasers is combined into a single beam Beam is relayed onto MEMS scanning mirror(s) Mirror(s) scan the beam in a raster pattern A projected image is created by modulating the lasers synchronously with the position of the scanned beam Applications: Pico-projection and heads-up display (HUD) Virtual and Augmented Reality (VR, AR) 3D Sensing and Advanced Driver Assistance Systems (ADAS)
New Applications Driven by Accuracy 11 Accuracy NAVIGATION PDR AUTONOMOUS DRIVING VIRTUAL & AUGMENTED OPTICAL IMAGE STABILIZATION REALITY Movement TGT 1 m <20 cm 10 cm <10 cm Noise Bias Instability Random Walk Stab vs. temp Arm Swing, Max error 1 m Total Distance 250 m Off & Sens tolerance
LSM6DSM 12 Google Daydream and Tango Certified http://www.st.com/content/st_com/en/about/media-center/press-item.html/t3874.html
STEVAL-STLKT01V1 SensorTile 13 IoT Design Lab on the tip of a pencil BLE Microphone MCU IMU Compass Pressure Sensor
STEVAL-STLKT01V1 SensorTile 14 IoT Design Lab on the tip of a pencil MP34DT04 BlueNRG-MS STM32L476 LPS22HB LSM303AGR LSM6DSM
MEMS Solutions For VR & AR Demo Details Sensor Expo 2017 San Jose June 28 th 2017
Virtual Reality (VR) Demo Provides real sense of presence & immersive experience using SensorTile Showcases low noise, drift and current consumption of our sensors (6X: LSM6DSL) and ST Sensor Fusion algorithms. MotionFx and ST MEMS sensors performances allow Low latency ( < 6 ms) to overcome motion sickness. Demo to be conducted with Google Pixel phone, SensorTile and Google Cardboard. SensorTile is connected to mobile device using USB and motionfx is running on SensorTile. SensorTile solid with CardBoard sends Sensor Fusion data Cardboard USB Android 7.0 Mobile running VR Reality App STEVAL-STLKT01V1 mounting: LSM6DSM / A + G LSM30AGR / A+M STM32L476 / MCU
VR: Basic Requirements for Sensors Minimum recommended sampling frequency for both Gyro and Accelerometer is 200Hz Low-Pass Filter cutoff is 30Hz for accelerometer and 50Hz for Gyro. For headset device, the head movement frequency spectrum must be acquired in entirety. Accelerometer bandwidth can be lower because we are not integrating acceleration. In Pixel Phone (Google Daydream) Gyro and Accelerometer can reach 400Hz maximum (Android N implementation).
Communication between Phone and SensorTile; System Architecture Phone Kernel needs to support Serial Communication over USB (ACM_CDC); Data is sent from SensorTile to Phone over USB; Algorithm used to achieve for common timebase for timestamping sensor data SensorTile and Phone; Sensor HAL receives data from USB and sync timestamps. Cardboard SensorTile solid with CardBoard sends Sensors and Fusion data USB Timestamp sync algo Android 7.0 Mobile running VR Reality App; HAL Layer
Android Device Requirements for VR MUST have at least 2 physical cores MUST support sustained performance mode. MUST provide an exclusive core to the foreground application The kernel must support cpusets and corethread affinity MUST support the Process.getExclusiveCores API to return the numbers of the cpu cores that are exclusive to the top foreground application. This core MUST not allow any other userspace processes to run on it (except device drivers used by the application), but MAY allow some kernel processes to run as necessary. Source: https://source.android.com/devices/tech/power/performance.html
Requirements for VR (Sensor Performance) Device implementations: are STRONGLY RECOMMENDED to support android.hardware.sensor.hifi_sensors feature MUST meet the gyroscope-, accelerometer-, and magnetometer-related requirements for android.hardware.hifi_sensors.
LSM6DSM is Daydream and Tango certified Android N HiFi sensor specifications cover the Tango specs LSM6DSM 21 Best-in-class 6-axis IMU GYRO Parameter Value LSM6DSM Stationary Bias Stability < 0.0002 /s * Hz from 24-hour static dataset Bias change vs. temp +/- 0.05 / s / C Best-Fit line Non-Linearity 0.2% Sensitivity change vs. temp 0.02% / C Noise Density 0.07 /s/ Hz XL Parameter Value LSM6DSM Stationary Noise Bias Stability <15 μg * Hz from 24hr static dataset Bias change vs. temp +/- 1mg / C Best-Fit line Non-Linearity 0.5% Sensitivity change vs. temp 0.03%/C
Thank you