Sentient Transportation Systems

Sentient Transportation Systems



[Using sensor networks for building a full fledged

transportation system for a township]





Mobile Computing Class

CEN 5531

Fall 2006

Sundara Dinakar

Moumita Ghosh

Shreyas Dube

Sentient Transportation Systems



 Sentient Systems

 Sentient Transportation Systems

 Integration of application areas:

– "Drivers Domain“

 Navigation

 Road and traffic information



– "Passenger Domain“

 Entertainment

 Information on vehicle performance

 Nice driving experience

Drivers domain – Navigation



 Before a journey, vehicles are notified about the virtual circuit (GPS )

waypoint information, vehicle builds RTImage (real-time perception)

 The cooperation between vehicles is critical to avoid collisions

(through sensors)

 CORS (Continuously Operating Reference Stations)

 A Dead-Reckoning (DR) system kicks in to complement the GPS

system

How do nodes communicate?



 City divided into zones

– Event based communication between

vehicles

– Using publisher subscriber model

– Vehicles have filters

Drivers domain – Congestion Control



 Access Points collect information about congestion in zones from vehicles

traveling there

 Different Access Points from the same zone and different zones form a peer to

peer network to exchange congestion information

 Vehicles record their speeds on each road, which when compared with the

roads' speed limits gives an indication of the degree of congestion. On entering

an area covered by a Wireless Access Point (AP), they report this data.

Inter-vehicle communication – MANET

(Mobile Ad hoc Network)



 Ad hoc networks operate without a fixed

infrastructure

 Multi-hop transmission

 Issues:

– Limited power

– Frequently changing topology

Multicast in MANET - Approaches

 Tree based

– Group of core nodes run a multicast tree

algorithm

– Topology information needed

– Not suitable for changing topology

 Mesh based

– Uses a mesh to support multicast

forwarding

– Inefficient: Control overhead

– Suitable for changing topology

 Flooding based

– No Control overhead

– Consumes too much network

resource

RISP

(Receiver-Initiated Soft-State Probabilistic multicasting

protocol)







 The source node initiates a session by

sending Beacon packets

 Upon receiving a Beacon, receivers send

Join_REQ packets to join the multicast

session and keep the session alive

 On receiving the first Join_REQ packet, the

source begins to send data packets

Example



 Link failure

 Link addition

RISP – Conclusion



 RISP introduces probabilistic forwarding and soft-

state for making relay decisions

 RISP can adapt to node mobility:

– At low mobility, RISP performs similar to a tree-based

protocol

– At high mobility, it produces a multicast mesh in the network

 Simulation results show that RISP has a lower

delivery redundancy than mesh-based protocols,

while it achieves higher delivery ratio

 The control overhead is lower than other protocols

Infotainment



 A pleasant driving experience.

– Nearest pizza shop

– Automatic Up/Down of window shutters

 Information about the vehicle

– Air pressure in the wheel

– Oil leak

- Brake failure





 Achieved thru a well-planned sensory platform

backed up with a powerful software framework.

Challenges in attaining infotainment:



 Pervasive system that enables seamless integration of mobile devices



 Web service connectivity / basic navigation / vehicle diagnostics.



 Upgradeable, flexible and reliable.



 Harsh conditions – extreme temperatures / dust / vibrations



 Graceful recovery from various faults.



 Performance



 Never cause a drain on the vehicle battery.



 Obedient to hard timing constraints regarding network bus responsiveness.



 Feature richness, Renewability, user interface.



 Prioritization of messages

The middleware



– CAN (Controller Area network) protocol stack to

deliver messages between Electronic Control Units

(ECU).









Prioritization of messages.

Characteristics Of Middleware



 Diagnostics

 Communication Services

 Device Management (over the air and USB)

 Power Management

 Speech Service

 Movement detection service

 Media player functionality

 GPS service

Finding obstacles in vehicles path



 Vision sensors to find change in the color of

the terrain.

 Creation of context awareness

Passenger domain – Infotainment



 Automotive Platform Components

Application HMI



HMI Framework





Applications

Software Integration









Development Tools

Application Framework





Middleware





Operating System







Hardware drivers





Hardware

Passenger domain – Infotainment



 Automotive Platform Components consist of:

– Hardware

– Drivers

– Operating System

– Application Framework

– HMI framework

– Application HMI

Other uses of Sensors in the System



 Stop at traffic signals (without human control)

 Use of RFID in rental cars( for inventory

control)

 Use vehicles as Environmental Sensors, to

collect large geospatial database

THANK YOU