IPERMOB follows a cutting-edge approach investing a set of techniques / methodologies explained below:

Model driven engineering

The IPERMOB project is created on the basis of a systematic development
methodology well known in software engineering, the Model-Driven
Engineering (MDE). The whole system is designed using standard
techniques and notations such as XMI and MOF by OMG. This approach eases
all activities connected to the development, including the specification
of the requirements of the system and its subsystems, the integration of
all components, test plan design, and the system verification. A
reference model has been developed in UML to support the MDE approach,
along with a glossary with an explanation of all relevant terms.

System Requirements,

Architecture and Test Plan

The IPERMOB system life cycle regards three main phases:

• Requirements definition;
• Architectural model specification;
• Test Planning.

The process is based on a spiral model with succeeding prototypes.

The Requirements definition has the main scope to define the system
requirements both in terms of functionalities and of Quality of Service.

The Architectural model specification depends both on system requirements
and on system model in agreement with the model-driven approach.

The Test Planning regards the integrated system validation and test with
the scope to succeed in the testbed prototype validation.

The focus of the  entire process are the end-users with their needs and
their uniqueness following a “user centered” design. In regard to this
approach some system requirements and tests are based on ergonomics of 
human-system interaction.

The Road Side and Vehicular devices

The solution adopted for the IPERMOB Data Collection Layer is based on Wireless Sensor Networks (WSNs) and Vehicular Ad-hoc NETworks (VANETs) technologies. Even if the main purpose of the project is the technological transfer, the WSNs and VANETs solutions adopted are very challenging, looking beyond the state-of-the-art for such kind of systems.

Concerning WSNs, a new paradigm in persavive data collection is pursued, by means of visual nodes (Visual Wireless Sensor Networks), ITS information is collected, on-board processed (data aggregation) and then sent to the upper layers of the system. The event changes are detected by means of low-complexity imaging algorithms and sent trough an IEEE802.15.4 based network to the system gateway. The network reliability in the WSN domain is guarantees by mans of Forward Error Correction (FEC) and Automatic Repeat reQuest (ARQ) techniques.

The VANET solution adopted in the project is based on the new IEEE802.11p standard which has recently released as official standard by the IEEE. The final IPERMOB testbed will be one of the first in the world adopting such kind of standard. By means of Vehicular to Infrastructure (V2I) communications car positions in GPS coordinate are sent to the IPERMOB control room, thus giving and getting informations about traffic conditions on road. As regarding the VANETs the IPERMOB project is mentioned on the web site of the Car-2-Car Communication Consortium.

The network infrastructure

The IPERMOB network infrastructure must satisfy the system requirements
regarding the scalability, the quality of service and the security.

The network infrastructure consists of two tiers:

• a collection tier where the sensor data are fused by the coordinators;
• a backhauling tier, where data from the coordinators and the Road Side Units are aggregated by the gateways and transmitted to the control room via broadband HiperLAN/2 links operating in 5 GHz unlicensed bands.

The Embedded Gateways (GWs) are responsible for collecting and forwarding the data coming from several sources assuring a suitable Quality of Service (QoS), by means of traffic shaping, packet scheduling, traffic policing, and packet dropping.

The data are coming from the vehicular and sensors networks and optional surveillance cameras. The data from the vehicular and sensors networks are a sequence of messages with the same form but different semantics.

The GWs allocate more or less bandwidth to the data coming from the different traffic sources and gives a priority to the messages managing several traffic queues and forwarding the data according to the chosen policy.

The data are forwarded from each gateway via HiperLAN to a software application called Message Manager (MM), that interfaces with the DBMS and Control Room.

The MM is in charge of collecting all the data coming from the different gateways and notifying the DBMS and control room services.

The data management system

The storage system includes three independent databases, the Event DB, the Offline DB and the Scenarios and Models DB. The Event DB is a real-time database that guarantees the persistence of the events reported by the Vehicular Network and the RSUs. The information about the events related to the status of the parking and the vehicle flows occurred in the network are collected and sent by the Message Manager to the Event DB. This information is then stored in a geospatial Database and returned when requested to the end clients from the road or the Control Room. Moreover, the Offline DB and Scenarios and Models DB can directly access the database tables to get historical data for their own usage. Since the amount of data handled by the Event DB can be very large on an urban scale, IPERMOB focuses on efficient database management techniques for timely execution of data retrieval  and update operations. In order to guarantee the highest possible throughput, the priority of the update operation is set to be higher than the priority of the retrieval methods.

The Offline Database is maintained and operates as a Data Warehouse, periodically importing data from the Online DB. The elementary records are generally aggregated in order to permit an efficient retrieval of pertinent “high level” information and optimize the storage on the long run (months, years). The information can be aggregated on different dimensions to generate “views”. The offline DB is important for the process of feeding the Scenario and Model DB and storing all the previous simulations.

The task of the Scenario and Models DB is to provide a realistic snapshot of the traffic patterns, called behavioral models. This DB is populated applying specific algorithms on the “views” of the Offline DB. The Scenarios and Models DB has a flexible structure that gives the opportunity to simulate several traffic scenarios: for example they could represent different hours of the day when the traffic conditions could have changed, restricted traffic (car-free) area could be open/close or streets could have been closed for construction sites. By means of the interaction of the simulations outputs provided by the Scenario and Models DB and the offline DB, it is possible to forecast traffic flows and parking occupation on a medium-long term.

The Service and Control Room (SCR)

The IPERMOB approach is that of providing an ergonomic space to the final users of the system. The final applications are subvided into three categories:

• real-time monitoring;
• infomobility;
• decision support.

Through a “Service and Control Room (SCR)” the applications are profiled towards the following classes of final users:

• public user (municipal authority, road manager);
• private user (driver, web visitor);
• system administrator.

IPERMOB wants to set-up the elementary blocks (in terms of applications and services) useful to support the more complex applications listed by the European Commission within the “Intelligent Transportation Systems”, i.e.:

• traffic and mobility management;
• traffic information delivery;
• public transportation management;
• fleet and freight transportation management;
• advanced vehicle and navigation control;
• emergency response management.

The implementation of services and applications in the SCR follows the approach of responding to open-ness and interoperability issues; the former permits to continuosly upgrade the list of applications while collaborating with others belonging to the community, the latter permits to access the SCR without relying on proprietary standards (thus making use of heterogeneous technologies).

Testbed

The IPERMOB testbed has the main scope to apply the technology to real world, scalable to typical urban surface, in order to provide services to citizens and to support the public authorities for their on-line monitoring activities and long-term planning.

As testbed, IPERMOB will provide real-time information about parking availability and vehicle speed and integrated flows on the landside of the “Galileo Galilei” Pisa International Airport. As regards the testbed the main activities includes:

• The preliminary system integration and test on laboratory.
• The system installation regarding the network infrastructure, the storage system and the service and control room.
• The system validation and test according to the test plan.

Download a brief presentation of the project