MEMS Solutions For VR & AR...VR: Basic Requirements for Sensors •Minimum recommended sampling...
Transcript of MEMS Solutions For VR & AR...VR: Basic Requirements for Sensors •Minimum recommended sampling...
MEMS Solutions For VR & ARSensor Expo 2017
San Jose June 28th 2017
Piezo actuatorsFluidicMicro-actuators
MicroMirrors
MEMS Sensors & Actuators at ST 2
Physical change
Mechanical
Signal
Electric
Sense
Actuate
MEMSElectro
Mechanical
Motion Environmental Audio
ST as MEMS Sensor & Actuators Supplier 3
Expertise in multi-sensor Integration
High Volume Manufacturing
Market-proven Manufacturing Technologies
Front-End / Back-End/ Testing & Calibration
Leading Smart Functions Integration
Key Partnerships in product
development
SENSINGACTUATING
20 Years of MEMS Sensors & Actuators 4
ST Innovations
2000 2005
Accelerometer Gyroscope Inertialmodule
Pressuresensor
2015
MicroMirrors
Piezoactuators
FluidicMicro-
actuators
Microphones UVsensor
2010
Humidity sensor
2008 2012 2013 2014 2017
GAS & VOC
ACTUATINGSENSING
20 Years of MEMS Sensors & Actuators 5
And Some Iconic Products
2000 2005 201520102008 2012 2013 2014 2017
MEMS Sensors & Actuators 6
ST Key Technologies - Enabling Multiple Applications
Piezo-Electric Electrostatic
Thermal Electro-magnetic
+
Sensors Actuators
ThELMA* AMR - MAG
VENSENS** Bastille Cactus
* Thick Epi-Poly Layer for Microactuators and Accelerometers** VENice SENSor
Changing the MEMS Landscape 7
Strategic PartnershipsPiezo Autofocus
MEMS Loudspeaker
Ultrasound Ranging
Micro-mirror Projection
What is a MEMS μMirror Scanner?
• Tiny reflective mechanical device that swings at a given frequency
• Applications spanning Visible to Invisible (IR typically) light
8
Laser Beam Scanning (LBS) 9
• 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
Technology Principles and Applications
Green LD
Red LD
Blue LD
MEMS scanning mirror
Laser Beam Scanning (LBS) 10
• 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)
Technology Principles and Applications
Movement TGT
Random Walk
Noise
Stab vs. temp
Bias Instability
VIRTUAL & AUGMENTED
REALITY
New Applications Driven by Accuracy 11
OPTICAL IMAGESTABILIZATION
AUTONOMOUSDRIVING
NAVIGATIONPDR
1 m <20 cm 10 cm <10 cm
Accuracy
Off & Sens tolerance Arm Swing, Max error 1 mTotal Distance 250 m
LSM6DSM 12
Google Daydream and Tango Certified
http://www.st.com/content/st_com/en/about/media-center/press-item.html/t3874.html
SensorTile 13
IoT Design Lab on the tip of a pencil
IMUCompass
BLE
Pressure Sensor
MCU
Microphone
STEVAL-STLKT01V1
SensorTile 14
IoT Design Lab on the tip of a pencilSTEVAL-STLKT01V1
LSM6DSMLSM303AGR
BlueNRG-MS
LPS22HB
STM32L476
MP34DT04
MEMS Solutions For VR & ARDemo DetailsSensor Expo 2017
San Jose June 28th 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.
SensorTilesolid with CardBoard
sends Sensor Fusion data
Android 7.0Mobile runningVR Reality App
USB
Cardboard
STEVAL-STLKT01V1 mounting:LSM6DSM / A + GLSM30AGR / A+MSTM32L476 / 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).
•
System Architecture• Communication between Phone and SensorTile;
• 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.
SensorTilesolid with CardBoardsends Sensors and
Fusion data
Android 7.0Mobile runningVR Reality App;
HAL Layer
Cardboard
USBTimestamp sync algo
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 21
Best-in-class 6-axis IMU
LSM6DSM is Daydream and Tango certified Android N HiFi sensor specifications cover the Tango specs
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
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°
GYRO
XL
Thank you