2. INTRODUCTION:
• The adaptive lighting system is a safety system designed to help you see more clearly at
night without affecting other drivers. The system may also help the driver to see more of
the corner when turning. This results in the driver being able to more easily see
pedestrians, animals, or stopped vehicles along their path of travel.
• An adaptive lighting system can have one or more functions depending on the vehicle
features. The headlamps can turn to better illuminate around corners based on steering
angle.
• The system often utilizes an in-vehicle camera. This camera is typically located near the
rearview mirror. The camera is used to detect oncoming traffic and vehicles in front of the
driver, and adjusts the headlamps accordingly.
3. WHAT IS ADAPTIVE LIGHTING SYSTEM:
• Adaptive headlights are headlights that actively respond to changing
conditions. Their goal is to provide drivers with better visibility and more time
to react to conditions ahead. It's a term that encompasses several different
features, most common of which is curve-adaptive headlights.
6. • When a vehicle is driven on the highway at night, it is required that light
beam should be of high density and should illuminate the road at a
distance sufficiently ahead. However, when a vehicle coming in the
opposite direction approaches the vehicle with a high-beam headlight,
driver of that vehicle will experience a glare, which may blind him. This
dazzle effect is one of the major problems faced by a driver in night
driving. To avoid this impermanent blindness, a separate filament is
usually fitted in the “dual-filament” headlight bulb in a position such that
light beam from this second filament is deflected both down and
sideways so that the driver of the oncoming car is not blinded.
• In practice, one mechanical dimmer switch is used by the driver to
manually select high (bright) or low (dim) headlight beam. However, this
is an awkward task for the driver especially during peak traffics.
8. WORKING OF THE CIRCUIT:
• This circuit is built around the popular timer chip NE555 (IC1). Here IC1
is configured as a gated-astable multivibrator running at a frequency of
about 1.5 Hertz ( duty cycle 75%),determined by the values of
components R1, R3 and C1. The whole circuit can be directly powered
from the 12V automobile battery.
• When power switch S1 is turned to “on” position, 12VDC supply from
the battery is fed to the whole circuit through polarity guard diode
1N4007 (D1). Capacitor C3 (100uF/25V) is a traditional buffer capacitor
to improve the circuit stability. Initially, astable built around IC1 is
disabled by the light sensor circuit realized using the 20mm – Light
Dependent Resistor (LDR),100K trimpot (P1) and BC547 (T1)
transistor.
9. • As a result output (pin 3) of IC1 is at a “low” level, and the 12V
electro-magnetic relay (RL1) connected at the output of IC1 is in “off
“state. The first LED (LED1) indicates this condition. As per the
wiring (+ve supply is routed to headlights through the N/C contacts
of RL1), headlights are in now in “on” condition.
• However, when a strong light falls on the LDR, IC1 is enabled
immediately and as a result its output goes “high” to energize the
relay.
• Now the downlights are powered by the N/O contacts of the relay
and stays in this condition until the light level on LDR is reversed.
• The second LED (LED2) indicates this condition. Note that, switch
for the ASM mode (S2), directly grounds pin 6 and 2 of IC1, when it
is in “on” mode and hence the astable function of IC1 is in disabled
state. If S2 is in “off” mode, the “ASM” function turns to “on” and this
flashes headlights and downlights rapidly, as long as strong light
level (from another headlight) is detected by the LDR.
10. PROMINENT FEATURES:
• 12V automobile battery powered automatic switching circuit with negligible current
consumption in standby mode
• Reliable and weatherproof light sensor module (Cds photocell)
• Independent variable control to set the “light detection sensitivity to avoid false
triggering caused by the influence of other light sources like streetlights
• Optional selector switch for “Automatic Signaling Mode” (ASM). In this mode,
dim/bright control of headlight is in pulsed, i.e. headlight automatically changes to dim
level from bright level and vice versa in a rhythmic style (like a signal to the other
motorists) when light from the front coming vehicle is detected by the light sensor
module
• “Energy Saving Mode” – If the circuit is in active state, by default, headlights
automatically goes off when the vehicle enters in a well-lighted area.
11. APPLICATIONS:
1. They allow for safer driving :
These systems allow automatic lighting on the road without the need for driver
interaction. The usefulness of these adaptive headlights involves the all-important task of
preventing accidents.
2. They avoid blinding other vehicles or pedestrians :
Adaptive headlights not only benefit the driver, but also other vehicles. For example, if
a two-way sloped road, the light pattern is reduced to prevent glare on oncoming drivers.
12. 3. They adapt better to driving conditions :
They have systems that are capable of detecting oncoming traffic and the taillightsof cars in
front of us. Based on this information, headlights are automaticallyturned on. The driver will
be able to use the highest beam without blinding other drivers.
4. They improve driving in adverse weather :
Driving in the rain or fog increases road accident rates. One of the factors is lackof visibility.
Adaptive headlights can help the driver even in adverse weather. For example, this type of
system activates anti-fog lights, and at a rate of speed slower than70 km/h, they rotate the left
headlight about 8 degrees outwards and 1 degree down.
13. CONCLUSION:
• The Adaptive Front Lighting System is a system which regulates
automatically the light distribution of a vehicle. A specific control
algorithm is developed for different driving conditions – curve
roads and incoming vehicle’s. AFS can be formally defined as
maintaining a presumptively desired light distribution adapted to
the above road environment. The system tested does so by way
of input from in-vehicle parameters like steering wheel angle
and distance between incoming vehicle and subject vehicle etc.