The Future of the Automobile Vehicle Safety Communications. Stanford University ME302 Luca Delgrossi, Ph.D. April 1, 2014

Transcription

1 The Future of the Automobile Vehicle Safety Communications Stanford University ME302 Luca Delgrossi, Ph.D. April 1, 2014

2 About your lecturer Luca Delgrossi, Ph. D. Born in Italy, I live in the US since 2005 Background in operating systems and networking 70+ scientific publications 2 books Automotive safety expert 8+ years with Mercedes-Benz R&D North America I teach this class since 2011 Your feedback is very important to me 2

3 Schedule Date Lecture 04/01 Introduction to Vehicle Safety Communications 04/08 Vehicle Architecture, Data, and Applications 04/15-04/22 Vehicle-to-Vehicle Communications 04/29-05/06 Vehicle-to-Infrastructure Communications 05/13 Research Projects (Prof. Seung-Wong Seo) 05/20-05/27 Project Presentation (Part I) 06/03 Project Presentation (Part II)

4 Contents Vehicle Communications Connected Vehicles Benefits Applications Taxonomy Communication Modes Communication Systems V2V Communications Traffic Safety Facts Automotive Safety V2V Safety Applications USDOT Initiatives Data & Applications Vehicle Architecture Vehicle Data Mobility Applications Safety Applications V2I Communications V2I Safety Applications Intersection Collisions Integrated Safety Demo USDOT Safety Pilot

5 Textbook Describes fundamental issues in cooperative vehicle safety Summarizes the history and current status of 5.9 GHz Dedicated Short- Range Communications (DSRC) Includes coverage of vehicle-toinfrastructure (V2I) and vehicle (V2V) communications Features an in-depth overview of onboard (OBE) and roadside equipment (RSE) Takes on security and privacy requirements and challenges ISBN (Wiley)

6 V2V in the Media

7 U.S. Department of Transportation

8 National Highway Transportation Safety Authority (NHTSA)

9 5.9 GHz DSRC Milestones NHTSA Decision Radio Ns-2 IEEE p ITS WC 3000 Users 700 Users CICAS-V VSCS Spectrum Allocation VSC VII-O VII-R VSC-A DAC V2V-I MD

10 Outline Connected Vehicles Benefits Use Cases and Applications Taxonomy Communication Systems Modes and Attributes Communication Technology

11 Connected Vehicles

12 Connected Vehicles Imagine vehicles could talk to other vehicles, roadside infrastructure, road users, What innovation could be enabled? What benefits for the traveling public? If they could talk, what would vehicle say?

13 Connected Vehicles A few definitions: V2V: Vehicle-to-Vehicle V2I or I2V: Infrastructure-to-Vehicle V2X: Vehicle-to-Device (any wireless device) The idea is that vehicles, roadside infrastructure (roads and highways), and back-end (telecommunications and Internet backbones) work together. Can you imagine what powerful services could be offered to drivers and other car occupants?

14 Benefits Extended connectivity Home and office activity continues in the car Connected travelers Enhanced driving experience Navigation, active points of interest Traffic management, mobility, and re-routing Improved safety Situation awareness Collision avoidance Post-crash assistance

15 Use Case: Pandora

16 Use Case: Texting with Ford Sync

17 Use Case: Mercedes-Benz Smart Drive

18 Use Case: Probe Data Collection

19 Application Taxonomy

20 Connected Vehicle Applications Disabled Vehicle Construction Zone Blind Spot Warning Forward Collision Warning Icy Bridge Hard Safety Soft Safety Live Traffic Updates Route Guidance Mobility Connectivity Off-Board Navigation Media Download Emergency Electronic Brake Light Intersection Movement Assist Convenience Tickets & Reservations Social Networking Point-of-Interest Notifications

21 Hard Safety Applications Hard safety applications are targeted to avoiding imminent crashes and minimizing the damage when these crashes become unavoidable. These applications impose the most stringent requirements on the communication system. The communication latency has to be minimized in order to offer the driver sufficient time to take action. The communication system must provide high levels of reliability such as high message reception probabilities.

22 Soft Safety Applications Soft safety applications are less time-critical Soft safety applications increase driver safety but do not require immediate driver reaction, because the hazards are not imminent. Examples include warning the driver of weather, road, traffic, icy roads, construction zones, reduced visibility, pot holes, and traffic jams. Typical actions in response to soft safety application alerts would be to proceed with caution or take alternate routes to avoid the dangerous conditions ahead.

23 Mobility, Connectivity, Convenience Mobility applications focus on improving traffic flow. Examples include navigation, road guidance, traffic information services, traffic assistance, and traffic coordination. Connectivity and Convenience applications focus on making driving more enjoyable and providing greater convenience. Examples include point-of-interest notification, , social networking, media download, and applications update.

24 Mobility, Connectivity, Convenience These applications can be delivered through: consumer electronic devices such as smart phones, or in-vehicle embedded devices Better integration with the vehicle can provide additional advantages. The vehicle s display and sound system can offer a user interface designed to minimize driver distraction. These applications can tolerate long delays but may occasionally demand high data throughput.

25 Non-driving Activity

26 Communication Systems

27 Communication Systems Connected vehicles require an efficient communication system. Can existing communication systems be adopted? 3G/4G Cellular (like your cellular phone) Wi-Fi (like your laptop computer) Are new communication systems needed? 5.9 GHz Dedicated Short Range Communication (DSRC) We need to consider what are the main attributes that differentiate one communication system from another and what are the applications requirements.

28 Communication Systems Attributes Attribute Unit Throughput Bits per Second Delay (Latency) Seconds Reliability Packet Error Rate Direction Unidirectional or Bidirectional SetupTime Connection-oriented or Connectionless Destinations Point-to-Point, Multicast, or Broadcast Range (Coverage) Meters Others: Hops, Cost, Availability, Confidentiality, Privacy,

29 Vehicle Communication Modes Infrastructure message dissemination servers Infrastructure application servers (c) I2V local broadcast (d) V2I bi-directional communications (e) indirect V2V (a) V2V local broadcast (b) V2V multi-hop forwarding

30 V2V Local Broadcast With V2V local broadcast, a vehicle sends messages to all other vehicles within its communication range. This communication mode serves as the foundation for cooperative applications aimed at collision avoidance. For example, vehicles can use V2V local broadcast to inform neighboring cars of each other s current position, heading, and speed. Since the set of neighboring vehicles changes frequently. short-range radios with native broadcasting capabilities are natural ways to support this communication mode.

31 V2V Multi-Hop Dissemination With V2V multi-hop dissemination, messages from one vehicle are relayed by other cars to reach vehicles that are outside the source vehicle s communication range. When the number of hops is very low, this mode can be used to support hard safety applications such as EEBL. V2V multi-hop message dissemination could also be used for soft safety purposes such as the distribution of hazardous road and traffic information. Note that the vehicles may not always form a connected V2V network.

32 I2V Local Broadcast Vehicles receive local broadcasts from the roadside infrastructure. For instance: Traffic controller signal phase and timing information, Dangerous road condition information, and Security credentials I2V local broadcast can be implemented through shortrange radio transceivers deployed along the roadside. It can also be implemented using cellular, satellite, or digital radio broadcast services to reach all the vehicles in a large geographical region.

33 V2I Bidirectional Communications Many mobility and convenience applications require the V2I bidirectional communications mode. Examples include navigation, Internet access for browsing or , electronic transactions for purchasing goods or services, and media download. V2I communications can also be used to broadcast messages from a vehicle to other vehicles through infrastructure applications servers. This mode can be supported using long-range or shortrange radios. Cellular networking capabilities have been increasingly used in vehicle telematics devices.

34 Communication Technology

35 Bluetooth Bluetooth is designed to support Personal Area Network (PAN) to replace wired cables between devices nearby. It operates in unlicensed 2.4 GHz Industrial, Scientific, and Medical (ISM) frequency band. Very low power consumption and short range (10 m) Bandwidth is adequate for audio and simple file transfers Bluetooth EDR theoretically supports 3 mbps (maximum application throughput is 2.1 mbps) Bluetooth HS supports theoretical data transfer speeds of up to 24 mbps (through link)

36 Bluetooth Bluetooth is increasingly used to pair mobile phones to vehicles. Such pairing enables hands-free calling from the vehicle It allows a vehicle s embedded display unit to be used to control mobile phones, and allows a mobile phone to use the vehicle s embedded sound systems. It also enables making emergency calls when the driver loses her ability to do so in an accident, downloading digital contents, infotainment, travel information, or software updates, and access to Internet or cloud applications.

37 Bluetooth Bluetooth can also been used for some vehicle-toinfrastructure communications when the vehicle is stationary or moving at very low speeds. These include allowing a vehicle to communicate with parking lot payment applications at a parking lot entrance. Bluetooth s limited communication range and high latency precludes its ability to support vehicle safety communications.

38 Wi-Fi (Infrastructure) Wi-Fi networks, defined in the IEEE standards, can support vehicle communications in their infrastructure mode. However, Wi-Fi hotspots have sparse coverage today and moving from one hotspot to another generally requires reconnection to the network. This could be tolerated by some non-safety vehicle applications.

39 Wi-Fi (Ad-hoc) Wi-Fi networks can support V2V local broadcasts through their native ad-hoc broadcast capabilities. However, modifications to the standards are necessary to reduce latency and achieve more reliable communications at high speeds in order to support vehicle safety communications. So far, IEEE technology is the closest to meeting most requirements of hard safety applications.

40 Dedicated Short-Range Communications This led to the development of Dedicated Short-Range Communications (DSRC) radio technology and standards. DSRC is essentially Wi-Fi in its ad-hoc mode adapted to support communications among vehicles moving at high speeds. DSRC can be used to create large-scale consumer vehicle networks able to support V2V and V2I communication modes.

41 3G Cellular Networks Third-generation (3G) cellular networks offer low latencies meeting the requirements of some hard and soft safety applications. However, current 3G networks lack effective ways to support V2V local broadcasts, which are essential to most hard safety applications. Furthermore, sharing bandwidth with voice communications could cause unpredictable delays and could also overload the cellular system. Also, the long call setup latencies can introduce excessive delays for hard safety applications.

42 4G Cellular Networks Long Term Evolution (LTE), offers significantly lower communication delay, higher capacity, and enhanced broadcasting capabilities compared with 3G cellular networks. LTE can support very small radio cells. These include microcells covering up to 2 kilometers, picocells covering up to 200 meters, and femtocells covering tens of meters.

43 4G Cellular Networks These small cells can be used to deliver even higher capacity and lower delay at hot spots such as homes, office building complexes, densely populated areas, and crowded road intersections. Therefore, LTE can support time-critical vehicle applications, including selected I2V local broadcast and some V2V safety applications.

44 3G/4G Comparison Criteria HSPA+ Rel. 8 LTE WiMAX e Theoretical Peak DL Data Rate (bandwidth) 42 Mbps (10 MHz) 73 Mbps (10 MHz) 40 Mbps (10 MHz) Average DL Data Rate (Field Testing) 3 Mbps* 5 12 Mbps 3 Mbps* Theoretical Peak UL Data Rate (Bandwidth) 12 Mbps (5 MHz) 58 Mbps (20 MHz) 12 Mbps Average UL Data Rate 1.3 Mbps* 2 5 Mbps 0.6 Mbps* Mobility Support Undeclared 350 Km/h 120 Km/h Latency 93 ms* 100 ms 199 ms*

45 Satellite Digital Audio Radio Service SDARS is a broadcasting network in which digital highfidelity (hi-fi) audio entertainment is transmitted from orbiting satellites to receivers on the surface. Signals can be received either directly from a satellite or by means of earth-based repeaters. Programming can also be received through Internet connections. SDARS satellites transmit radio frequency signals at approximately 2.3 GHz.

46 Satellite Digital Audio Radio Service The first satellite was launched in 2001 by XM Satellite Radio. The second was launched in 2002 by Sirius. SDARS users pay a nominal monthly fee for the satellite radio service and in turn receive programming that contains almost no advertising. The programming consists mainly of music but also includes news, weather, sports and traffic information. The services are used primarily by motorists although receivers can also be installed in residences and businesses.

47 DSRC Wi-Fi Bluetooth 3G 4G LTE SDARS Range 100s meters 100s meters Up to 100 meters 10s Km 10s meters to 100 Km Countrywide End-to-End Delay 10 ms 10 ms 10 ms ms 10s ms sec Call Setup Time Not needed 3-5 s 3-4 sec 100s ms to seconds ~50 ms Not applicable V2V Local Broadcast Yes Yes Impractical With a server With a server No V2V Multi-hop Yes Yes Impractical With a server With a server No I2V Local Broadcast Yes Yes Impractical Not offered by all network operators Not offered by all network operators Yes V2I Bidirectional Yes Yes Impractical Yes Yes No

48 Questions Which connected vehicle applications do you envision? Which communication systems would you adopt? What tangible benefits for the users?