The basic structure of the measurement trailer is a four-axle truck trailer. The frame of the trailer has been cut in half at the middle point to allow for an axle with equipment to measure a tyre installed on the axle. The measurement tyre can be loaded up to six tonnes, turned around on the vertical and longitudinal axis, and also braked as a separate unit in the future. The interaction between the tyre and road contact surface is measured using camera technology and various sensors whose data is processed with software specially developed for this purpose.
The construction of the measuring equipment and the changes in the structure of the trailer have been planned as the master's thesis of the machine design research group and carried out at the university workshop. The measurement software has been developed in cooperation with the Intelligent Machines and Systems research unit at the University of Oulu.
Measuring the tyre forces generated by truck tyres with the measurement trailer in Ivalo in March 2020. The study is related to a joint Swedish-Finnish project that analyses, classifies and compares different types of tyres to develop standard tyre models for large HCT vehicles (description: University of Oulu, Materials and Mechanical Engineering research unit)
The smart measurement trailer allows for collecting data on the operation of tyres on different driving surfaces more accurately, more quickly and in a more versatile manner than before. Studying the impact of various HGV tyre parameters, such as tyre pressure, tyre temperature, wear and rubber hardness, on various driving surfaces and in a wide range of speeds throughout life cycle of a tyre is ground-breaking research. Particular attention is paid to different types of winter driving surfaces as there is little research available regarding HGV tyres in this area. The measurement results will also allow simulating the behaviour of vehicles and vehicle combinations with different types of tyres and driving surfaces.
The study of a vehicle's tyre forces creates a cornerstone for the study of driving dynamics, as tyre forces are the only thing keeping the vehicle on the desired path. This is particularly important when examining the introduction of heavier vehicle combinations and the possibilities of autonomous driving. By developing tyre models suitable for different conditions, we can significantly affect the energy efficiency as well as tyre safety of vehicle combinations, thus reducing emissions.
New possibilities for tyre manufacturers
Researchers from the University of Oulu have cooperated with Nokian Heavy Tyres and Swedish companies VTI, Volvo and Scania in the development of the new tyre measuring equipment. According to Teppo Siltanen, Product Manager of Nokian Heavy Tyres, the new measuring equipment enables fast and reliable tyre testing.
“The specification of tyre modelling parameters can now be carried out in Finland, whereas previously similar measurements have been made in foreign testing facilities. The aim of our research is to get our hands on the optimisation of tyre parameters, which can be utilised in the product development of HGV tyres. HGV tyres have a major impact on how environmentally friendly road transport is as well as road safety, of course”, says Siltanen.
The measurement trailer was developed as part of a multidisciplinary ERDF project implemented at the University of Oulu, funded by the Regional Council of North Ostrobothnia. The project concerned the development of an arctic testing environment for autonomous machinery and vehicles at the University of Oulu campus and the Ouluzone Motorsport Centre. The project developed a research, development and testing environment where independently moving vehicles can interact in a versatile and smart manner with their environment and each other. The testing environment complements the research, development and training possibilities of autonomous cars at the OuluZone test centre owned by the City of Oulu.
Photo: The basic structure of the measurement trailer is a four-axle truck trailer. The middle point of the frame has an axle with equipment to measure a tyre installed on the axle (images: Ville Pirnes)
Last updated: 30.6.2020