Microrobotics benefits paper industry
TUT’s expertise in microrobotics is boosting the development of low-density, cost-effective and yet high-quality paper. Professor Pasi Kallio coordinates the international PowerBonds project that develops methods for measuring the bond strength between paper fibres.
The strength of paper is largely dependent on the properties of individual paper fibres and inter-fibre bonds. If the strength of the bonds can be improved, paper manufacturers will be able to replace expensive fibres with cheaper fillers, such as chalk and clay.
In the ongoing battle to cut costs, manufacturers are looking to reduce the basis weight of their paper products without compromising quality. Stronger inter-fibre bonds would enable the production of more low-density and thereby more light-weight paper and save on the raw materials and energy needed to manufacture and deliver the products. In addition, better bond strength would help prevent web breaks resulting in expensive downtime in paper mills.
Paper fibres are cells
Researchers at TUT have conducted research into microrobotics for nearly two decades. According to Professor Pasi Kallio, they spent the first ten years refining the required technology and have since then shifted their focus to processing living cells.
"Paper fibres are cells, too, so we decided to find out how paper manufacturers could benefit from our expertise," says Kallio.
In 2006, initial contacts were established with an international pulp and paper research forum through COST, the European Union’s intergovernmental framework for cooperation in science and technology. After two years of discussions and careful planning, the PowerBonds project started taking shape and was finally launched in early 2012. It is coordinated by the Department of Automation Science and Engineering at TUT. The three-year project is funded under the EU’s WoodWisdom-Net 2 Research Programme and involves seven companies and eight academic partners from Finland, Sweden, Germany, France and Austria.
Stereo vision and artificial intelligence
TUT’s role in the PowerBonds project is to develop automatic methods for measuring the strength of individual fibre bonds. Paper fibres are typically one millimetre long and around 30 microns in diameter.
"The first measurements were taken by gluing the fibres to the sensor. Our goal is to build a microrobot that is capable of identifying and capturing fibres in a liquid solution using stereo vision and artificial intelligence. The system should be intelligent and fully autonomous," says Pasi Kallio.
The measurements will generate a wealth of data that can be used, for example, to develop computational models of fibre bonds and make accurate predictions of the strength properties of paper.
"In addition to paper, our solution can potentially be applied in the study of other fibrous materials."
Special expertise in biological applications
The highest priority of most research groups involved in microrobotics is the development of microelectronics assembly applications. Right from the outset, researchers at TUT have stood out from the rest by focusing on biological applications.
"Other leading groups are also in the process of integrating artificial intelligence into their systems, so we’re definitely not lagging behind our competitors", says Pasi Kallio.