This document summarizes research on driver usage of speed regulation systems like cruise control (CC) and speed limiters (SL) using naturalistic driving data from several European countries. The main findings are: 1) Drivers use CC predominantly on highways and rural roads in good weather and free-flowing traffic conditions. CC engagement periods tend to last 1-10 minutes. 2) Drivers typically select cruising speeds slightly above the legal speed limit, around 3 km/h faster on average. 3) SL usage varies more between drivers and road types compared to consistent CC use. Some drivers consistently use SL at the speed limit while others exceed it, especially on highways. 4) There

1. INTERACTION WP4
Speed Regulating Systems
Context and modalities of use
Corinne Brusque (IFSTTAR)
INTERACTION Final Event
22 November 2012, Brussels

2. Sample and vehicle description
Naturalistic driving data used for speed regulation system analysis
Country Nb drivers Nb of trips Hours driven Km driven
Finland 15 593 395 17306
France 16 1495 698 34751
Spain +
13 334 210 6961
Portugal
Car models
Country Nb of cars CC SL brands
Finland 5 Yes No Volkswagen
France 5 Yes Yes Peugeot / Renault
Spain +
5 Yes yes Peugeot
Portugal
Final Event 22 November 2012 2

3. Homogeneity of the data
• Some differences between countries
– Not the same IVT on all the country vehicles :
difficulties to find intensive users
– Some technical glitches with the data : GPS
speed not stored
– Not the same amount of data enriched with
video coding : hard to obtain use rate if
everything is not coded.
Use rates of IVT cannot be compared
Only french Data suitable for speed analysis
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4. Results
• Do all drivers use speed regulation
systems in the same way ?
• Do driver have preferences ?
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5. A typology of speed regulation systems users :
Exclusive CC; Exclusive SL; mixed
exclusive CC users
100.00% 0.00%
exclusive SL users • Finland:
mixed CC/SL users
15 CC
0% 50% 100%
exclusive CC users
• France:
46.67% 53.33%
exclusive SL users 15 CC; 8 SL
mixed CC/SL users
0% 50% 100%
• Spain/Portugal
exclusive CC users
7.69% 92.31%
exclusive SL users 13 CC; 12 SL
mixed CC/SL users
0% 50% 100%
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6. Results
• About CC use
– Context of use
– Modality of use
• About SL use
– Context of use
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7. When do driver choose to use CC ?
• Study of the context of use in terms of
– Road environment (From GIS)
 Highway
 Urban
 Rural
– Weather (coded from video)
 impacting the drivers behaviours
 not impacting the drivers behaviours
 Extreme weather conditions
– Traffic (coded from video)
 Free flowing driving conditions
 Constrained by other drivers
 Extreme traffic conditions
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8. Context of CC use Influence of road type ?
% Hours driven
with CC on
40.30% 50.30% Highways
Finland 9.40%
% Hours driven
with CC on Rural
roads
• 3 drivers filtered on spain/port data due
0% 50% 100% to a too minor time spent using CC (less
than 20mn in total).
% Hours driven
with CC on
Highways • CC use mainly on highway or rural
87.05% 11.60% % Hours driven roads.
France 1.35% with CC on Rural
roads
• Differences of rural road types according
% Hours driven
with CC on Urban
countries: more or less curves.
0% 50% 100% roads
• CC use on urban roads: marginal in
France, 10% in Finland and Spain/Port:
more driving at night ? (need to go back
to the data to understand)
Spain/Portugal
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9. Context of CC use Influence of traffic ?
% Hours driven with
CC on Free flowing
traffic conditions
87.76% 12.24% % Hours driven with
Finland CC on constrained
traffic conditions
% Hours driven with
CC on traffic jam
0% 50% 100%
Free flowing conditions with
% Hours driven with no impact on driving represent
CC on Free flowing more than 85% CC situations
traffic conditions
1.65% for all the countries.
France 98.27% % Hours driven with
0.08% CC on constrained
traffic conditions
% Hours driven with
CC on traffic jam
0% 50% 100%
% Hours driven with
CC on Free flowing
traffic conditions
Spain/Portugal 91.99% 7.97% % Hours driven with
CC on constrained
0.04% traffic conditions
% Hours driven with
CC on traffic jam
0% 50% 100%
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10. Context of CC use Influence of weather?
Hours driven with CC
Finland
• CC use mainly on good weather
conditions
• Differences on weather conditions
and experimentation periods in
% Hours driven with
the countries compared.
CC on weather
conditions no
impacting drivers
• Breakdown of CC use according
France 85.68% 14.32% behaviour weather condition similar to the
% Hours driven with profile of weather conditions in
CC on weather
conditions impacting
each country.
drivers behaviour
0% 50% 100%
Spain/Portugal
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11. Extracts of Renault, Opel, Fiat, Peugeot and
Ford owner manuals
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12. How do driver use CC ?
• Study of the use of CC controls
– Frequency of interactions
– Length of the CC engagement sections
 Section of the trips when CC was engaged
– Selection of the cruising speed
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13. Number of +/- hits and speed setting changes
Modality of CC use
per hour driven with CC
Finland
• Finland: Less interactions with the CC
France than France and Spain/Portugal
Spain/Portugal
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14. Modality of CC use length of CC engagement sections
% of short CC
sections (<= 1 min)
Finland 35.59% 51.34% 13.07% % of medium CC
sections (> 1 min
&<= 10 min)
% of long CC
sections (> 10 min)
0% 50% 100%
• Half the sections and more are during
more than 1 minute and less than 10 mn.
France
• On highway at 120 km/h: section
between 2 and 20 km.
• 1/3 CC section < 1 mn in each country.
Spain/Portugal
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15. Modality of CC use Illustration of CC use strategy
Highway trip time line
5 min
Exit road work and traffic tunnel
toll gate overtaking under traffic junction

16. Modality of CC use
Selection of cruising speed vs. legal speed limit
• For France
• There are not significant
Drivers ID Car model 110km/h 130km/h
differences on speed gap
401 308 3,7 4,5
402 308 -1,2 -1,6 according to the value of
403 308 1,6 4,5 the legal speed limit.
404 clio -1,7 2,4
405 308 7,2 5,5
406 clio 7,2 1,4 • 13/15 of the drivers in over
407 308 3,7 2,5
408 207 5,3 3,7 speeding
409 clio
410 207 8,1 -9,7
411 308 6,7 4,9 • Drivers select a cruising
412 207 6,6 5,1
413 207 11,4 3,6
speed slightly superior to
414 308 3,6 2,2 the legal speed limit. In
415 207 5,9 12,2
416 207 18,1 0,5
average, the difference is
Mean Clio 1,9 equal to 3 km/h.
308 3,21
207 2,57
Std Clio 0,71 • No effect of the car model.
308 2,45
207 7,16
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17. How do driver choose to use SL ?
• Study of the context of use in term of
– Road environment (From GIS)
 Highway
 Urban
 Rural
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18. Breakdown of SL use according to road type (A3)
France
At the difference of CC, SL is
used in the different road
contexts
Spain/Portugal
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19. A typology of SL users
If CC users can be considered as an homogeneous group, it is not the
Legal 50km/h 90km/h 110km/h 130km/h case for SL users
speed limit
Data Data Data Data
filtered filtered filtered filtered
402 79,40 88,3 Caution:
403 57,70 88,4 Data Filtered when the
404 54,70 time driving with SL in
407 84,40 108,6 122,60 135,5 the legal speed limit
411 62,50 zone is below 15 mn.
412 68,00 94,8
414 126,80 118,1 134,10 135,3
416 118,50 112,8 132,60 135,6
• Exclusive highway SL users:
• Setting speed on highway is very homogeneous, 5 km/h above
the legal speed limit
• No change the setting speed when they get away from highway
and drive on another road type.
• Exclusive urban roads SL users:
• The setting speed fits more the legal one.
• Mixed rural/urban roads SL users:
• No adaptation setting speed to legal one when driving on
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urban area (small villages crossed during the trip). 19

20. Are there interactions between
systems ?
• Sutdy of the number of calls on Highway on
free flowing conditions according CC use
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21. MP calls on Highway on free flowing conditions according CC
use(C1)
Spain/Portugal
France
France: Significant effect of the CC use but not on the way expected (Wx=3.23, p<0.001).
Spain/Portugal: no significant effect bur same tendance.
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22. Thank you for your attention
Final event – November 22, 2012 - Brussels 22