With the increasing urban
population, corporate offices, malls there is a subsequent increase in traffic
congestion. It is always a challenging task to work on the smart parking.
Thanks to the evolving technologies, parking facilities have been advanced. The
existing works on smart parking are not transparent. Many advanced solutions on
multiple issues regarding the parking problems have been proposed, while some
are being implemented. To provide a clear overview on the proposed advancements
and the progress regarding the smart parking, we provide literature over the
past and present advancements and summarize the existing techniques and throw
wide open our insights regarding the efficiency of the technologies in use. Our
paper provides an all-inclusive insight into the smart parking besides throwing
wide open future research opportunities in the smart parking domain.
On average, 30 percent of traffic is caused by
drivers wandering around for parking spaces 3. In 2006, a study in France
revealed an estimation that 70 million hours were spent every year in France
only in searching for parking which resulted in the loss of 700 million Euros
annually 4. In 2011, a global parking survey by IBM 5 stated that 20
minutes are spent on average in searching for a coveted spot. With these
statistics, we can predict that a great portion of global pollution and fuel
waste is related to cruising for parking 6.
the ever running hectic schedule people are finding it frustrating to waste
their essential time searching for free parking lots. So if drivers can have
real-time parking availability information, they will be able plan accordingly
and stop cruising their vehicles all around the parking areas in vain. So there
is a need to assuage the search time, reduce pollution caused due to emission
of greenhouse gases by the vehicles and reduce fuel consumption through
efficient parking system.
solution lies in smart parking system. It helps to Share the information prior
through technology and alleviate the traffic congestion. Once the traffic is
free flowing it also contributes to the increase in traffic mobility easing the
process for the transportation facilities.
OF PARKING SYSTEMS
A. Centralized assisted parking search
assisted parking search the central server takes provides the information to
the users. Sensors present in the parking lots detect the presence of vehicles
and the corresponding information regarding availability of free slots is
maintained by the server.
B. Non-assisted parking search
parking search do not rely on the technology. Users does not receive any data.
The user has to cruise his vehicle all around the parking lots searching for a
free slot. The first user to reach a vacant parking slot gets the opportunity.
C. Opportunistically assisted parking search
There is a new
approach called opportunistically assisted parking search (OAPS), which uses a
Mobile Storage Node (MSN). The information flow is made with this MSN. This
leads to increase further through its efficiency.
D. Parking Guidance and Information System
In PGI systems the users receive information
about the availability of parking spaces areas through Virtual Message Signs
(VMS) on the road or through the internet.
A PGI system typically consists of 4
main components: parking monitoring mechanism, parking space information
dissemination, telecommunications network and control center.
PGI systems use bar-code machines to
count vehicles making an entry or leaving a particular parking area. The major
drawback in this system is that the availability is not made sure to the
driver. Whereas some PGI systems vehicle detection and scrutiny use sensors or cameras
by placing them in the parking area.
Based Information System (TBIS)
based information system (TBIS) provides guidance for park-and-ride facilities
5, 6. This system succeeds in implementing, and it reduces the
inconvenience of the users.
methods such as payment through parking meter where cash counters are placed
require a lot of maintenance and staff for handling efficiently. Smart payment
systems provide the best solution to the existing problem. Using RFID
technologies the payment is made by Automated Vehicle Identification (AVI) tag.
This RFID technology and mobile devices are contact less methods where cards
can be recharged periodically. Also there are contact methods which include
smart cards, debit cards and credit cards, which users are more prone to use
daily. However the main concern lies in in security and privacy issues because
all the details regarding the users are shared on to a database which can be
exploited. Therefore particular measures have to be taken for secure
In this system
the drivers take the cars to the bay, safely lock them and allow the Computer
controlled mechanism to safely park the car. This system places the car in its
allocated space by computer-controlled docks/lifts and sometimes user
participation is required. These type of parking can be efficiently used in
areas where parking areas do not have the scope for expansion and it allows car
stacking. Besides this it also important to ensure that the vehicle remains
safe and secure without any damages considering the slightest scratches. The
systems have to design perfectly so that it ensures all kinds of security
measures. If there is any malfunction in these computer controlled machines it
leads to loss of vehicles. An introduction of three-level software design which
includes: Logical Layer (LL), Safety Layer (SL) and Hardware Abstraction Layer
(HAL) to implement the correct and efficient storage of vehicles in a safe
provides scope for the users to know the availability of vacancy spot prior to
reaching the destination SMS or the internet is used for efficient E-parking.
looks for the availability of parking space the algorithm searches for the
shortest distance to find the nearest parking area and checks for the
availability there. Including smart payment system mechanism make sit more
efficient as the users can book the parking slot even before reaching the
destination. For reservation mechanism mobile phones or reservation centers are
used. Wireless Application Protocol (WAP) enabled mobile phones 9, and
Personal Digital Assistants (PDAs) are also used by this system 10.
Park Occupancy Information System
Video sensors are used in this
system for vehicle detection. The image processing techniques are used to
detect the vehicles and the display board displays the count of vehicles. This
may not be efficient as compared to others. But this helps to organize the
cars, trucks, and lighter vehicles by image processing techniques and segregate
them and allot a separate areas for a particular type of vehicles.
When the occupancy status changes, a sensor can detect a vehicle’s
presence or absence and updates the information in a short time
SFpark 4, in
San Francisco, allows that 85% of events are received within 60 seconds on
large-scale roadside parking sensor networks. The latter takes advantage of the
vehicle’s mobility to collect information along the route with fewer sensors.
Mobile sensors can detect the occupancy status when they pass through a parking
Reservation System (PRS)
Reservation system would require
the between the users and the PRS. Real time monitoring of the vacancy and the
demand based anticipation are the key features in this system. The anticipated
demand depends on the number of people who have already booked the slot and the
expected number of non-reserved arrivals during the next few time periods that
could be based on historical arrival data. The users can reserve though SMS or
the online websites or the apps, where they would receive the allotment details
K. Intelligent Transport System (ITS)
ITS systems are a set of
information, communications and technologies for vehicles and infrastructures
focused on the transport 13. The information can be offered by an accurate
vehicle classification using WSNs.
Parking Assist System (IPAS)
Driver attention free system which
helps the car to be parked. This system was designed for reverse parallel
parking. It can automatically place the car by guiding the vehicle
appropriately. This system is also known as Advanced Parking Guidance System
M. App based parking assist system
Users use an
app in smartphone to find the availability of parking slot. Parking sensors are
connected to nearby multi-service parking meters. But most of the users aren’t
satisfied with this as there would be a disadvantage to non-smartphone users.
So, Non-smartphone users can pay their parking spaces, get current parking
availability in the city, and obtain tourism or public transportation
information simply by multi-service parking meters. The total implementation
cost of the system is estimated at 15 million euros.
Different types of sensors implemented in various parking
quest for a reliable and cost-effective vehicle detection and tracking system,
which can be installed and maintained with safety and minimal disruption of
traffic has been underway for some time. Recent evaluations have shown that
modern aboveground sensors produce data that meet the requirements of many
current freeway and surface street applications. Aboveground sensors can be
mounted above the lane of traffic they are monitoring or on the side of a
roadway where they can view multiple lanes of traffic at angles perpendicular
to or at an oblique angle to the flow direction. The technologies currently
used in aboveground sensors are video image processing, microwave radar, laser
radar, passive infrared, ultrasonic, passive acoustic array, and combinations
of sensor technologies such as passive infrared and microwave Doppler or
passive infrared and ultrasonic. Like the subsurface sensors, the aboveground
sensors measure vehicle count, presence, and passage. However, many also
provide vehicle speed, vehicle classification, and multiple-lane, multiple-detection
sensors are placed to detect approaching or departing traffic or traffic from a
side-looking configuration. They are classified into active and passive
Active infrared sensors illuminate
detection zones with low power infrared energy supplied by laser diodes. The
infrared energy reflected from vehicles traveling through the detection zone is
focused by an optical system onto an infrared-sensitive material mounted at the
focal plane of the optics.
infrared sensors with a single-detection zone, measure volume, lane occupancy,
and passage. The source of the energy detected by passive sensors is gray body
emission due to the non-zero surface temperature of emissive objects. When
a vehicle enters the sensor s field of view, the change in
emitted energy is used to detect the vehicle as illustrated in Figure 27. A
vehicle entering the sensor s field of view generates a signal that is
proportional to the product of an emissivity difference term and a temperature
difference term when the surface temperatures of the vehicle and road are
reverse parking sensor
reverse parking sensor find its place in the rear bumper of the vehicle. The
sensor has to be drilled in to the bumper which contributes to its uncertainty
as it is located outside the rear bumper, and it stands out for everyone to
see. Also as it is placed outside it has to be maintained properly from the
external damaging factors.
Electromagnetic parking sensor
This is the
advanced version of ultrasonic reverse parking sensor. The electromagnetic
parking sensor fits behind the car bumper to make it almost invisible. It is
also more reliable than an ultrasonic parking sensor. It helps to detect
objects even at the sides of the bumper. This reverse parking sensor is an
asset to your vehicle.
Inductive loop detectors
Detectors (ILDs) are wire loops of various sizes, which are exited with signals
whose frequencies range from 10 to 50 kHz. It functions as an inductive
element in conjunction with the electronics unit. When a vehicle stops on or
passes over the loop, the inductance of the loop is decreased. The decreased
inductance increases the oscillation frequency and causes the electronics unit
to send a pulse to the controller, indicating the presence or passage of a
vehicle. The data supplied by conventional inductive loop
detectors are vehicle passage, presence, count, and occupancy. Although loops
cannot directly measure speed, speed can be determined using a two-loop speed
trap or a single loop detector and an algorithm whose inputs are loop length,
average vehicle length, time over the detector, and number of vehicles counted.
The two axis
fluxgate magnetometer detects in the vertical and horizontal components
of the Earth s magnetic field produced by a ferrous metal vehicle.
The second type of magnetic field sensor is the magnetic detector, more
properly referred to as an induction or search coil magnetometer. It detects
the vehicle signature by measuring the change in the magnetic lines of flux
caused by the change in field values produced by a moving ferrous metal
encompasses: Anisotropic Magnetoresistance Sensors (AMR), Giant
Magnetoresistance Sensors (GMR), magnetic Tunnel Junction Sensors,
Extraordinary Magnetoresistance and Ballistic Magnetoresistance that are simply
energized by providing a constant current 3. The AMR sensor in their research
for vehicle detection and has noted its sensitivity to position and
piezoelectric is a specially processed material capable of converting kinetic
energy to electrical energy. These properties are exhibited by some polymers to
a high degree. These types of materials are ideal for manufacturing piezoelectric
sensors. The standout advantage of using the piezoelectric sensor is to gather
information on the tire passing over the sensor, rather than on the passing of
a vehicle. They detect the passing of the tire over the sensor, thus generating
an analog signal that is proportional to the pressure exerted on the sensor.
This unique ability of piezoelectric sensors allows them to segregate 4-11
individual vehicles with extreme precision. In addition, on an installed cost
basis, they are only marginally more expensive than an inductive loop, but
provide significantly more information in the form of improved speed
information, the ability to determine the classification of the vehicle, and
the capability to determine and monitor the weights of vehicles for WIM
The Vehicles are detected by air
pressure created, which closes a switch, and produces the signal when the
vehicles pass over it 3. It is easy to implement and maintain, but it is
temperature sensitive. And sometimes in accuracy is resulted.
The weight of vehicles is detected
and this data is useful to highway planner, designers and law enforcement
agencies 3. The four technologies used in it are bending plate,
piezoelectric, load cell and capacitance mat.
This sensor transmits energy
through an antenna and detects a vehicle by the energy reflected back towards
the antenna 3. The two type’s radar sensors are Continuous wave radar (CW),
and Frequency modulated continuous-wave radar (FMCW). They are insensitive but
Doppler sensors would have to be equipped with auxiliary sensors in an attempt
to detect stopped vehicle.
Passive acoustic Array Sensors
Acoustic sensors measure vehicle passage, presence, and
speed by detecting acoustic energy or audible sounds produced by vehicular
traffic from a variety of sources within each vehicle and from the interaction
of a vehicle s tires with the road. When a vehicle passes through the detection
zone, an increase in sound energy is recognized by the signal-processing
algorithm and a vehicle presence signal is generated. When the vehicle leaves
the detection zone, the sound energy level drops below the detection threshold
and the vehicle presence signal is terminated. Sounds from locations outside
the detection zone are attenuated.
The Ultrasonic sensors transmit
pulse waveforms between 25 to 50 kHz to the road by detecting transmitted
energies, which are reflected back the sensor. They are easy to install but are
sensitive to the environment.
2. Ultrasonic Sensor
broadcast information and guide drivers to corresponding parking spaces fairly
becomes an important issue.
divide service dissemination into three parts as well: information dissemination,
parking competition, and drivers’ behaviors.
vehicles can exchange messages, parking information, traveling from
infrastructures to drivers, will be able to be retransmitted to other drivers
in a multi-hop network
fixed sensors can execute a sensor-to-vehicle communication with passing cars,
or cars equipped with sensorsNr1 can exchange their detected information with other cars in a
vehicle (sensor)-to-vehicle network. The latter usually can retransmit receipt
messages in a multi-hop manner.
1 168, namely city-based parking routing system, proposed a centralized
parking system that links intelligent lampposts and parking sensors by
power-line communication. The central parking service runs an ant colony optimization
(ACO) to guide drivers from their current location to parking spaces. The
results show that ACO outperforms the Dijkstra’s algorithm in reducing traffic
congestion and increasing city flow
1 170 introduced a smart parking system using a search algorithm to find
the most suitable parking spaces as soon as possible.
Various techniques have been implemented to deliver the status
of sensors to a particular database or server. Bluetooth/BLE, 802.11ah (Wi-Fi HaLow)
and ZigBee/ Z-Wave/Digi Mesh, or long-range, like Sigfox, LoRa, Weight-less,
Ingenu and NB-IoT/LTE-M
Urdiain et al tested the leach routing protocol on the
Arduino platform which is used as the parking sensor.
Benson et al used
the DSYS25 sensing node to experience packet delivery rates with
parked vehicles. If either senders or receivers are covered by parked cars,
communication reliability in the range of 0 to 5 meters is good. If senders and
receivers are both covered by parked cars, no communication is possible
Asaduzzaman et al proposed an ARM-based sensor node
equipped with ZigBee, Bluetooth or Wifi and compared their corresponding
transmission time and energy consumption. The results showed that ZigBee is the
best choice in terms of sensor lifetime and maximum connected nodes in mesh
Vishnubhotla et al introduced
a parking vacancy monitoring system with a ZigBee based WSN to show the parking
status in the entrance.
Tang et al designed a parking detection
where each parking space is equipped with a light sensor to detect a car’s
presence in order to provide real-time occupancy information.
Yang et al. 1 104
designed a WSN-based smart parking system that collects information totally
wirelessly. User interfaces are developed on smart-
a central web-server, and embedded web servers to guide users where available
parking spaces are.
Sens-City 1 102, 103 implemented a
Machine-to-Machine (M2M) architecture including parking sensors and parking
applications. To improve smart parking system intelligence.
et al. 1 122 used CAN bus to connect all ultrasonic parking sensors
and then provided a guidance service by an outer screen and light indicators.
Smart Parking addressed a software and hardware architecture for their smart
CHALLENGES AND OPEN
The future extension
requires the mature technology of the future generation of mobile network (5G),
and packets often travel farther among many central units and are billed.
Short-range communication allows some small-size deployment for local service.
Data transmission is often unlimited and compatible with present wireless
Current smartphone apps
used by drivers cruising on the street are not proactive. A content-based and
context-aware parking service facility will be needed, allowing to match
drivers’ interests and display parking information in advanced drive assistance
systems. Vehicular networks are more sensitive to urban environment, especially
on urban propagation, mobility, and drivers’ behaviors. A more realistic
dataset describing vehicular activities shall be collected and modeled to
evaluate and improve smart parking systems from the user end.
info can be shared on a network or among various drivers?