Device rocked by sea waves

The device will contain a set of pendulums set in motion by rocking waves. This in turn will drive the generator and produce electricity. The unit can be powered not only by the movement of waves, but also by other types of vibrations, for example by shocks on a train.

 Head of research, Prof. Tomasz Kapitaniak from the Department of Dynamic Engineering, Łódź University of Technology admitted in an interview with PAP that the device would not generate enough energy to, for example, supply a town, but it could supply signal lights located places difficult to access, like on buoys or fishing nets at sea.

The researcher pointed out that replacing batteries in such locations is a tedious and expensive, as it is necessary to sail to each buoy. If the signal light had its own little wave "power plant", battery replacement would not be needed. The generator could be more efficient than solar panels: it would also work at night, even during the very long polar night. A 10 cm device would be sufficient to power a buoy light, and regular movement of waves it is not necessary for it to work.

Research on the project is partly funded by TEAM programme of the Foundation for Polish Science. The researchers have developed a model of the device and carried out the first tests at a pool. The next step will be to build a prototype.

Prof. Kapitaniak explained that inventions already exist that use the motion of waves to generate electricity, but his team’s solution will be the first to use pendulum synchronization mechanism.

Prof. Tomasz Kapitaniak explained that pendulums moving in the same rhythm and placed next to each other, but set in motion separately, are capable of spontaneous synchronization. For the synchronization to occur, the pendulums should have the same period of vibration and the flow of energy (information) between them is required.

A spectacular example of such synchronization placing metronomes on mobile stand and releasing them to move independently of each other.

It turns out that after few minutes the devices can tune in to each other and strike one rhythm together. The scientist added that similar phenomena as in this experiment would occur in the current generator. However, in the device, all pendulums will be placed inside the cabinet, on one string, and one of them will be electronically powered and give the rhythm of the whole group of pendulums rocked by waves.

The researcher explained that synchronization occurs not only in the case of pendulums, but also in other systems in which regularity is observed. "The synchronization of human steps occurred during the opening of the Millennium Bridge in London" - recalls the expert. When the crowd entered the bridge, steps were chaotic. The bridge started to oscillate and forced people to adjust steps to oscillation and walk in the same rhythm, causing even greater movements of the bridge.

This represented a threat to the structure, and the bridge had to be closed immediately after opening.

Synchronization of oscillatory systems also occur sometimes in the case of ... menstruating women. It happens that women who live together (for example, in a dorm room) or work together in a small space, menstruate at the same time. In turn, within a single organism, synchronized operation of multiple cells can be a dangerous - as happens in the case of neurons. This phenomenon leads to Parkinson's disease. "Neurons should act erratically" - admitted the researcher. In these cases, however, the exchange of information between oscillating systems occurs differently than in the case of pendulums.

Spectacular synchronization may also occur, for example, in the colony of fireflies that can emit light at the same time.

The researcher explained that females adjust the flickering of their lights to a male. "Soon I'm going to Bolivia to study this phenomenon" - revealed Prof. Kapitaniak.

Source: PAP - Science and Scholarship in Poland, Ludwika Tomala