A chat with David Blažević
With the recent increase in the number of free-grazing farm animals, an area of interested has opened up in Animal-Computing to look at ways to monitor and keep track of animals whilst they are out alone foraging. One way this has been proposed is through tracking and monitoring animals whilst they are out in nature. However, with the environmental impact of depletable batteries and the human cost of farmers time and effort to track down their animals for this task, innovative ways have to be invented to power the devices that we use on animals. After Dr David Blažević, a researcher from Tampere University, got his PhD in energy harvesting methods, he went to work on a farm as a goat herder in Šumber, Croatia where he got the idea to combine the two fields.
Building upon this original spark, and working experts in numerical modelling of electromagnetic devices Prof. Paavo Rasilo and Dr. Janne Ruuskanenin, Dr Blažević seeks to convert animals locomotion (movement) into electrical power to power wearable animal devices. In this way, animals could power the monitoring devices themselves while grazing. In the future, energy harvesters could be a crucial part of welfare monitoring for farms, from individual animal health to herd health (such as disease spreading) to monitoring shelter and pasture conditions.

From his current research in Tampere University (Finland), Dr Blažević speculates that the most suitable animals for future energy harvesters are those that are the most agile. Yet he believes that all animals, including non-domesticated animals such as wildlife, also be possible candidates. However, for now, his project ENTRAP (Energy Harvesting for Precision Agriculture Applications) focuses upon two extremes of movements – cows being the least active grazers of the farm world and goats being highly agile.
When assessing where to place these energy harvesters on animals, he speculates that the best place on animals is those with lots of motion. For example, the ears for cows and the neck or leg for goats. However, while Dr Blažević believes that all free grazing animals can be equipped with some form of wearable – there are situations in which animals should not use wearables depending upon how big and adequate the technology is for the circumstances. This is one of the main challenges in building wearable systems for animals, that the computerised device should not hinder the animals’ normal movement whilst equally converting the maximum amount of energy, remaining light, and robust. As Dr Blazevic put it “farm scenarios won’t tolerate flimsy design“.


Tackling this problem Dr Blažević has been using 3D printing to rapidly prototype in the lab, which after they are satisfied with how they are built can quickly be transferred to animal hosts in the field to measure their performance and movement measurements there. As Dr Blažević states upon 3D printing “This is extremely helpful – the second day of field measurements – the eastern Finn cattle named Neilikka broke off the sensor casing – but it was printed new that same day using stronger material and improved design“.

The next steps for this research group is to look at ways for pain free ear movement logging and after collecting the results from the cows to further use the method devised with cows on goats and reindeer.
To find out more about Dr Blažević’s research, you can read more upon their researchgate project that has regular updates.