Project Objectives

Although the satellite navigation technology is nowadays available for the mass market, and it is broadly used in surveying, partly used in earth moving, it could not find its way to enter the asphalt road construction sites. The most crucial point is the high cost of the real time precise positioning technology. The ASPHALT project aims at developing a cost and precision optimized solution taking the advantage of the European satellite navigation systems (EGNOS and Galileo) and close coupling of the positioning system with the machine control/monitoring system.

The ASPHALT project addresses the application of the paving process on a road work site, in particular:

mass flow control from asphalt plant to the paver (fleet management)
paver steering
thickness measurement and control
evenness measurement and control
temperature measurement while paving
compaction monitoring and control by pass counting

supply chain for asphalt construction

Asphalt truck fleet management - mass flow

The objective is to reduce the waiting time of the trucks in front of the mixing plant but also in front of the paver. This reduces the number of required trucks and minimizes wasted time in front of the plants and pavers.

Asphalt truck fleet management - docking

The docking between the truck and the paver is a critical process. A supporting system shall enable soft-docking and reduce any dumps in the road resulting of hard-docking. Further the time for docking shall be reduced.

Paver leveling control system

The contract awarding authority defines a minimum thickness of the new asphalt layer. Going below this limit means for the construction company to rebuild the road. Exceeding the limit means a waste of material and money. A supporting system will help to meet the limit and provides the possibility for a continous documentation. The continous build-in process and thickness control will also result in high evenness of the asphalt layer. The supporting system will, furthermore, allow to steer the paver what facilitates road construction.

Compactor system

The important parameter for compaction is the temperature, which shall never drop below 80°C. The compactors continuously drive back and forward in order to achieve the optimal compaction. Thereby the compactors shall pass the same parts of the road several times. A supporting system will help to count the number of passes and indicate the overlap between passes. This will optimize the number of passes and reduce the time needed for compaction. Furhtermore it will result in a better road quality.

Objectives

The objective of the project is to develop a system for machine control and fleet management on a construction site, which enables building roads of better quality and durability. Especially the mass flow of asphalt and the optimization of different machine control loops as well as quality dependent measurement systems can bring a significant improvement of the process. The envisioned improvements are based on positioning information from satellite navigation - GNSS in general - Galileo, EGNOS, EDAS, GPS in particular.

ASPHALT high-level system design of the positioning component