Research Article
On-Road Driver Monitoring System Based on
a Solar-Powered In-Vehicle Embedded Platform
Yen-Lin Chen,
1
Chao-Wei Yu,
1
Zi-Jie Chien,
2
Chin-Hsuan Liu,
1
and Hsin-Han Chiang
3
1
Department of Computer Science and Information Engineering, National Taipei University of Technology, Taipei 10608, Taiwan
2
Department of Energy and Refrigerating Air-Conditioning Engineering, National Taipei University of Technology,
Taipei 10608, Taiwan
3
Department of Electrical Engineering, Fu Jen Catholic University, New Taipei City 24205, Taiwan
Correspondence should be addressed to Hsin-Han Chiang; hsinhan@ee.u.edu.tw
Received 16 May 2014; Accepted 16 June 2014; Published 3 July 2014
Academic Editor: Ching-Song Jwo
Copyright © 2014 Yen-Lin Chen et al. Tis is an open access article distributed under the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Tis study presents an on-road driver monitoring system, which is implemented on a stand-alone in-vehicle embedded system and
driven by efective solar cells. Te driver monitoring function is performed by an efcient eye detection technique. Trough the
driver’s eye movements captured from the camera, the attention states of the driver can be determined and any fatigue states can
be avoided. Tis driver monitoring technique is implemented on a low-power embedded in-vehicle platform. Besides, this study
also proposed monitoring machinery that can detect the brightness around the car to efectively determine whether this in-vehicle
system is driven by the solar cells or by the vehicle battery. On sunny days, the in-vehicle system can be powered by solar cell in
places without the vehicle battery. While in the evenings or on rainy days, the ambient solar brightness is insufcient, and the system
is powered by the vehicle battery. Te proposed system was tested under the conditions that the solar irradiance is 10 to 113 W/m
2
and solar energy and brightness at 10 to 170. From the testing results, when the outside solar radiation is high, the brightness of
the inside of the car is increased, and the eye detection accuracy can also increase as well. Terefore, this solar powered driver
monitoring system can be efciently applied to electric cars to save energy consumption and promote the driving safety.
1. Introduction
Te economic development has caused large amount of
energy to be consumed, and largely consumption of petro-
chemical inventories, resulting in the energy crisis. To reduce
the petrochemical energy consumption on vehicles, the elec-
tric cars arise. In order to achieve higher endurance driving,
we should care about the car battery power. Te in-vehicle
instruments in the electric cars also consume electric energy
and may reduce the energy for car driving. Moreover, there
are many trafc accidents which occur due to the inattentive
and fatigued driving. Tus, an efective monitoring system
for drivers’ attention states is also very important for the
development of electric cars. Terefore, the solar energy can
be adopted to drive the in-vehicle embedded computing
platform to conduct the driver monitoring functions, and
both the electric energy consumption and the driving safety
can be efectively achieved.
Photovoltaic (PV) technology is one of the most impor-
tant renewable sources of energy generation. Since the frst
recognition in 1839 [1], there have been many research works
on the performance of PV. However, efciency improvement
and cost reduction of PV technology still need many eforts.
Te solar cells based on crystalline silicon (c-Si) are known
as materials in frst generation solar cell [2]. From the points
of view on the cost, performance, and processibility, the
applications of new advanced materials such as amorphous
silicon (a-Si), cadmium telluride (CdTe), and copper indium
gallium diselenide (CIGS) are achieved in the second and
third generations of solar cells. Typical conversion efciencies
of frst generation technologies are currently 15% to 20%,
whereas those of second generation technologies are cur-
rently 7% to 15% [3].
Photovoltaic system can be categorized as stand-alone
photovoltaic system and grid-connected photovoltaic system
[4]. Te stand-alone systems do not supply power to the grid.
Hindawi Publishing Corporation
International Journal of Photoenergy
Volume 2014, Article ID 309578, 12 pages
http://dx.doi.org/10.1155/2014/309578