CADRE NAV08Presentation November2008 Tim Thornton Smartcom - PowerPoint PPT Presentation

CADRE
 
•
 NAV08
Presentation 
 November
2008
 Tim Thornton Smartcom Software tt@smartcomsoftware.com CADRE NAV08 Slide 1

Congestion
 CADRE Avoidance
 Dynamic
 Routing
 Engine
 Vehicle routing and traffic speed models for the real world Slide 2 NAV08

CADRE System
Overview
 Slide 3 NAV08

CADRE The
Congestion
Problem 
 Slide 4 NAV08

CADRE How
To
Tackle
Congestion 
  Build more roads  Reduce use of vehicles on the roads  More use of roads at low congestion times  More use of uncongested roads CADRE Travel time predictions at different times Better route selection Dynamic vehicle routing Slide 5 NAV08

CADRE Overview 
 Roadside
 GPS
 sensors
 vehicle
 data
 Mobile
 phone
 data
 Speed
 reports
 Road
 Speed
 network
 limits
 Speed
 model
 Route
 requests
 Speed
 Routing
 Speed
 engine
 engine
 data
 
Routes
 Road
 network
 Slide 6 NAV08

CADRE Architecture 
 Routing Data Client Logger Routing Journey Data Information Snapping Map Routing Engine Server Engine Speed Engine Short Term Model Long Term Model Road Journey Network Data Specific Road Generic Road Data Model Data Model Data Slide 7 NAV08

CADRE Journey
Data
 Mobile
Phone
 Reject
Bad
 Data
Ingest
 or
Logger
 Data
 Reject
 Add
to
Data
 Unsnappable
 Snap
to
Roads
 Store
 Data
 Slide 8 NAV08

CADRE Snapped
Data
 Snapping Development (since improved – about 90% pass rate) Green OK, Blue failed, since improved, Gold other journeys. Slide 9 NAV08

CADRE Speed
Engine
Scales 
 Slide 10 NAV08

CADRE Long
Term
Speed
Engine
  Core long term model in place  Provides speeds for each road segment varying by time of day and day of week  Long term model in process of improvement  Short term model being developed in Matlab Slide 11 NAV08

CADRE Generic
Speed
Model
  For
roads
where
there
is
no
specific
model
  Spread
of
data
currently
being
reduced
by
better
modelling
  Model
training
also
being
enhanced
and
automated
 A
road
dual
carriageway,
70mph
speed
limit,
Monday
 Slide 12 NAV08

CADRE Arc
Specific
Model
  A
model
is
created
for
a
specific
arc
once
there
is
enough
data
of
good
 enough
quality
  The
model
is
based
on
the
generic
one
for
that
arc
and
then
recalculated
 using
the
data
for
that
arc
 Slide 13 NAV08

CADRE Short
Term
Model
  Aim
is
to
detect
congestion
from
live
traffic
data,
and
then
create
a
short
 term
predictive
model
based
on
that
  This
part
of
the
speed
model
is
still
in
the
initial
modelling
phase
 Speed LTM STM Data Time
of
day Now Slide 14 NAV08

CADRE Routing
Engine
  Minimum time or minimum distance route  Uses speed limit or CADRE speed model or speed model capped by speed limit  Optimised for time varying road speeds  Heuristics, such as pruning, to aid performance  Always finds the true optimal route Slide 15 NAV08

CADRE Routing
Engine
 Slide 16 NAV08

CADRE Hindhead
Traffic
Lights
  Journey time using speed engine is more accurate than using speed limit data or via Michelin  Routing shows that in this case it pays to stay on the congested main road for almost all of the time, rather than to divert down narrow country lanes Slide 17 NAV08

CADRE Routing
Client 
 Slide 18 NAV08

CADRE Sample
Results
‐
Hindhead
 Minimum Time – Speed Limit Minimum Distance Slide 19 NAV08

CADRE Sample
Results
‐
Hindhead
 Minimum Time – Minimum Time – Speed Speed Engine – 12.30 Engine – 08.00 Slide 20 NAV08

CADRE Results
Comparison 
 Hindhead 12.30 Red distance, Blue time Slide 21 NAV08

CADRE
 
•
 NAV08
Presentation 
 November
2008
 CADRE NAV08 Slide 22