Volume 21
Issue 4/volume21
Forestry
JOURNAL OF
POLISH
AGRICULTURAL
UNIVERSITIES
DOI:10.30825/5.ejpau.163.2018.21.4, EJPAU 21(4/volume21), #04.
Available Online: http://www.ejpau.media.pl/volume21/issue4/volume21/abs-04.html
ROBOTIC FOREST HARVESTING PROCESS USING GNSS SATELLITE POSITIONING DATA: EFFECTS OF GNSS TRAJECTORY INACCURACIES IN FOREST ENVIRONMENTS
DOI:10.30825/5.EJPAU.163.2018.21.4
Anna Klamerus-Iwan 1, Louis-François Pau2, Mariusz Kormanek3, Janusz Goł±b1, Krysztof Owsiak 1
1 Department of Forest Engineering, Faculty of Forestry, University of Agriculture in Krakow, Poland
2 Copenhagen Business School, Denmark
3 Department of Forest Work Mechanization, Faculty of Forestry, University of Agriculture in Krakow, Poland
ABSTRACT
In agriculture and forestry, errors in position and directional information provided by high accuracy global navigation satellite systems (GNSS) lead directly to economic, productivity and environmental losses. The paper focuses on GNSS inaccuracies in the context of kinematic robotic forest harvester operations once a tree has been located. This represents a significant challenge as the geographic location of individual points using GNSS receivers largely requires an unobstructed line of sight from the points to a minimum number of satellites. This is often difficult to achieve in forest environments, as trunks, foliage and humidity can attenuate the GNSS signals besides multipath effects. It is shown by measurements and modeling that the harvesting process trajectories mandate high priority to be given to 3-D location and directional information. Extensive measurements of GNSS inaccuracies on radial grids around a tree position inside forests, some of the very first, have been carried out with the assistance of the Polish Forest Administration Authority. Data acquisition took place in three different forest environments in Poland, characterized by differences in tree heights, species, terrain slope, and rain/humidity levels. Combined with a directional volumetric tree trunk and canopy harvesting model, the data collected allow estimating the yield and productivity direct effects of GNSS errors on precision forestry equipment. It is shown that acceptable yields on trunk wood and logs can be achieved in some types of forest with few robotic harvester moves, in that to some extent the GNSS errors can be compensated by the telescopic arm flexibility of the harvester. The additional use of assistive lidars and other sensors, not considered here, strengthen these conclusions.
Key words: forestry, harvesting, robots, GPS, GNSS, accuracy, yield, economy.
Anna Klamerus-Iwan
Department of Forest Engineering, Faculty of Forestry, University of Agriculture in Krakow, Poland
al. 29 Listopada 46
31-423 Kraków
Poland
Phone: +48 601 652 707
email: annaklamerus.iwan@gmail.com
Louis-François Pau
Copenhagen Business School, Denmark
Solbjergplads 1
DK 2200 Copenhagen
Denmark
email: lpau@nypost.dk
Mariusz Kormanek
Department of Forest Work Mechanization, Faculty of Forestry, University of Agriculture in Krakow, Poland
al. 29 Listopada 46
31-423 Kraków
Poland
Phone: +48 12 662 5024
email: rlkorma@cyf-kr.edu.pl
Janusz Goł±b
Department of Forest Engineering, Faculty of Forestry, University of Agriculture in Krakow, Poland
al. 29 Listopada 46
31-423 Kraków
Poland
email: rlgolab@cyf-kr.edu.pl
Krysztof Owsiak
Department of Forest Engineering, Faculty of Forestry, University of Agriculture in Krakow, Poland
al. 29 Listopada 46
31-423 Kraków
Poland
Responses to this article, comments are invited and should be submitted within three months of the publication of the article. If accepted for publication, they will be published in the chapter headed 'Discussions' and hyperlinked to the article.