Advanced Embedded Systems for Wireless Applications · PDF fileAdvanced Embedded Systems for...
Transcript of Advanced Embedded Systems for Wireless Applications · PDF fileAdvanced Embedded Systems for...
Advanced Embedded Systems for Wireless Applications
Presented by:
Ludy Liu
Autoliv Electronics Inc.
Lowell, Massachusetts
USA
Internet Of Things - What are the product trends?
• Smart Appliance – Refrigerator can tell you it’s time to order grocery.
• Autonomous Driving System (ADS)
• Advance Driving Assistance System (ADAS)
• Health Monitoring – Help people to stay healthy and monitor health
• Security and Surveillance System – Cameras, Bio-Sensing
• Tracking Systems – People, Objects
• Cloud-Based Customer Service and Data Collection – Predict buying trend and enhance user experience
• System On Chips
Car with Advanced Drive Assistance System (ADAS)
Autoliv - Develop Active Safety features for Autonomous
Driving System/Future Car
•Active Safety - Crash prevention. Save lives.
•Automotive radar devices
•Adaptive Cruise control systems -If driver does not take appropriate action in time and a crash is
about to happen, advanced radar systems can take control of
the vehicle to avoid the crash or lessen the accident’s severity.
-Direct a vehicle’s accelerator and braking systems.
-Control distance between vehicles.
•Radar sensors
-Range
-Angle
-Doppler velocity
-Determine driving situation
-Warn driver in potentially dangerous event
Smart car equipped with Wi-Fi, Bluetooth and Satellite communication.
Radar Sensor
Car Camera
Rain Detector
Display
Monitor
Satellite Radio
Device
Wearable Health Monitoring System
Wi-Fi
Accelerometer Proximity
Sensor
Battery
Sensor Real
Time
Clock
Microprocessor User
Interface Flash ROM
Display
GPIO
I2C Bluetooth
Device
Timers
UART SPIs
Server
data
data
Heart Beat
Sensor
Wireless Network with Multiple Sensors
Cloud-Based Network Management Services
Network
Management Device
Feature
Upgrade
Device
Authentication
Encryption/D
escrption
Data
Analysis Bandwidth
Management
Network Time
Synchronization
Subscriber
Service
Architecture Considerations for Advanced
Embedded Systems
• How does the architecture look like?
• What features need to be provided?
• Server Connection – Automatic product upgrade, Over The Air Software Download
• Processor Performance
• Wi-Fi Enabled
• Bluetooth Enabled
• Sensors – Accelerometers, Proximity, Gyroscope, Infra Red Sensor
• Image Processing/Pattern Recognition
• Tracking capability
• Real Time Clock
• Memory Requirement
• Power Saving Mode
How to make architecture decision?
Competition – What is out there already? What is not out there?
• Price vs Quality
• Accuracy vs Speed
• Performance Driven
• Market/Price Driven
• Standard Driven
• Time To Market
Processor Selection for Wireless Embedded Systems
Real Time Clock Power
Saving
Mode
16-32 Bits 48 Mbytes RAM
SOC
Bluetooth
Wi-Fi
GSM/3G I2C UART
SPI Floating
Point
Flash/EEPR
OM
Wireless Embedded System Design Challenges
Software processing bandwidth may become an issue
in the case when multiple events are triggered by multiple sensors within a
single device.
If there are multiple devices within a dense network,
Time Synchronization support among all devices within a network
is important.
It may be difficult to choose what real time operating system is suitable.
Performance benchmarking of commercial available RTOS
may be necessary.
Real Time Operation System (RTOS) – Task Prioritization
Tasks typically supported by a wireless embedded system:
• Network communications – Relatively long latency w.r.t
other tasks, retry is necessary sometime.
• Wireless communications –Relatively long latency w.r.t
other tasks, retry is necessary sometime
• Device driver communications – Timing is usually
predictable, Interrupt driven.
• Sensor Trigger Events – Critical events must have
relatively higher priority.
• Measurement Task – Timing is usually predicatable.
• Main Loop – Run Periodically.
Wireless Embedded System Mini RTOS
Mini RTOS design approach:
• Design State machine flow to reflect the entire program
flow of the embedded system to be implemented.
• Implement main loop according the pre-defined state
machine.
• Estimate task timings.
• Use timers and timer interrupts to trigger tasks according
to pre-defined cycle time.
• Use interrupts instead of polling for wireless and network
communication code.
Internet Of Things Example: Car-To-Car Wireless Communication
Link:
https://www.car-2-car.org/index.php?id=5
Link:
https://www.car-2-car.org/index.php?id=171
Vehicle with Advance Driving Assistance System Demo Video
https://www.youtube.com/watch?v=etn-WMlpEHc