This document summarizes the different types of traffic signals: (1) Traffic control signals include fixed-time signals, vehicle-actuated signals, and manually operated signals. Fixed-time signals operate on a repeating fixed cycle, vehicle-actuated signals detect vehicle presence to alter signal timing, and manually operated signals are controlled by an operator. (2) Pedestrian signals control when pedestrians can cross. (3) Special traffic signals include green arrow signals that indicate permitted turning movements and flashing signals that convey special instructions.

1. TYPES OF TRAFFIC SIGNALS
PREPARED BY:-
RATHOD JAYDEEP (166250306546)
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2. TYPES OF TRAFFIC SIGNALS
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(A) Traffic control signals
(1) Fixed-time signals
(2) Vehicle Actuated Signals
(3) Manually operated signals
(B) Pedestrian signals
(C) Special traffic signals

3. Typical traffic signal
Traffic lights alternate the right of way accorded
to road users by displaying lights of a standard
color (red, yellow/amber, and green) following a
universal color code.
In the typical sequence of color phases:
• Illumination of the green light allows traffic to
proceed in the direction denoted,
• Illumination of the yellow light denoting, if
safe do so, prepare to stop short of the
intersect and
• Illumination of the red signal prohibits any
traffic from proceeding.
• Usually, the red light contains some orange in
hue, and the green light contains some blue,
the benefit of people with red-green color
blindness.
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4. (1) Fixed-time signals
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• These signals are set to repeat
regularly in fixed cycle.
• Cycle regulates yellow, red and
green lights in a fixed way
• Generally, duration of green
and red light are same
• Time duration of light is
dependent on traffic flow,
traffic flow should be
minimum.

5. (2) Vehicle Actuated Signals
 Vehicle-Actuated Signals require actuation by a
vehicle on one or more Re approaches in order for
certain phases or traffic movements to be serviced.
 They are equipped with detectors and the necessary
control logic to respond to the demands placed on
them.
 Vehicle-actuated control uses information on current
demands and operations, obtained from detectors
within the intersection, to alter one or more aspects
of the signal timing on a cycle by-cycle basis.
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6. Disadvantages
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Type Disadvantages
Fixed time Signals *Inflexible
*Cause Avoidable delay
Vehicle-Actuated signals *Require Costly
equipment such as
detectors
Semi Actuated Signals *High traffic accidents
at times of light traffic

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Advantages
Type Advantages
Fixed time Signals *Simple Construction and
*Inexpensive
Vehicle-Actuated signals *Flexible to adjust accord
to traffic demand
*Delay is minimized to
attain maximum capacity
Semi Actuated Signals *Useful for junctions of
a low traffic volume

8. Pedestrian signals
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9. Green arrow signal
You may proceed in
the direction of the
green arrow.
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