Noggrannhet av RTK-GPS-positionering av enskilda frön vid precisionssådd
(2023) In CODEN:LUTEDX/TEIE EIEM01 20231Industrial Electrical Engineering and Automation
- Abstract
- With higher demands on farmers to reduce the usage of fertilizers and pes ti cides because of their negative environmental impact, as well as the rising prices of resources required for agriculture, precision agriculture has become a big focus in today’s agriculture research. Individual plant care systems are a big part of precision agriculture, and accurate information about the po si tions of individual plants is required for these systems. In collaboration with RISE Research Institutes of Sweden and Väderstad AB, a seed mapping system for the planter Väderstad Tempo was developed. The system was designed to determine the individual seed positions by receiving geographical coordinates from a real time kinematic global positioning system... (More)
- With higher demands on farmers to reduce the usage of fertilizers and pes ti cides because of their negative environmental impact, as well as the rising prices of resources required for agriculture, precision agriculture has become a big focus in today’s agriculture research. Individual plant care systems are a big part of precision agriculture, and accurate information about the po si tions of individual plants is required for these systems. In collaboration with RISE Research Institutes of Sweden and Väderstad AB, a seed mapping system for the planter Väderstad Tempo was developed. The system was designed to determine the individual seed positions by receiving geographical coordinates from a real time kinematic global positioning system (RTK-GPS) in con junc tion with signals from the seed sensor already installed on the planter. A sec on dary task in the project was to isolate the error sources which would af fect the final error of the positioning. Variation in the GPS system’s reported coordinates as well as variation in the seed fall time from the seed sensor to the ground were investigated.
Seed fall times were measured in laboratory conditions where the type of crop, air pressure in the seed housing, and angular velocity of the seed disc were varied in order to build a mathematical model of the seed fall time. The de via tion metric root mean squared error (RMSE) of maize, sunflower, sugar beet, and cereal were 2.97 ms, 4.58 ms, 1.72 ms and 3.23 ms respectively.
Measurement of the variation of the RTK-GPS system was conducted in conjunction with the final tests of the system in a field. On average, the latitude and longitude had a RMSE of 4.17e-8 degrees and 6.38e-8 degrees respectively, which corresponded to a RMSE of 4.6 mm northing and 4.0 mm easting at the specific location of the measurements.
The seed mapping system was tested in a field under operation velocities in the range 5-15 km/h with the crops maize and cereal. After the seed mapping process, the seeds were found and positioned in a combination of RTK-GPS and manual measuring in order to determine their actual position. In the planter's driving direction, it was found that a seed could be found within a distance of 62.34 mm of a mapped seed position with a 95% probability.
The errors investigated for the seed fall times and RTK-GPS measurements turned out to only account for a small part of the total error of the seed mapping system. The remaining error stems from other parts of the process and needs to be investigated further. (Less) - Popular Abstract (Swedish)
- Enligt EU-direktiv måste fler tekniska lösningar introduceras i lantbruket med bakgrund till de ökande miljökrav och ekonomiska påtryckningar i världen. Som svar på detta har redan tekniskt styrda radrensare och styrd besprutning börjat etableras på marknaden. Till skillnad från individuella plantvårdssystem som kamerastyrda radhackor, kan GPS-styrda system identifiera fröpositioner innan uppkomst och även när förhållande för bildigenkänning är svårt på grund av väder eller mycket grönska.
Som ett examensarbete vid Lunds Tekniska Högskola i samarbete med RISE och Väderstad har en prototyp för frökartläggning utvecklats. I jämförelse med liknande GPS-system är detta systemet utvecklat för konventionella såmaskiner. Ett system som... (More) - Enligt EU-direktiv måste fler tekniska lösningar introduceras i lantbruket med bakgrund till de ökande miljökrav och ekonomiska påtryckningar i världen. Som svar på detta har redan tekniskt styrda radrensare och styrd besprutning börjat etableras på marknaden. Till skillnad från individuella plantvårdssystem som kamerastyrda radhackor, kan GPS-styrda system identifiera fröpositioner innan uppkomst och även när förhållande för bildigenkänning är svårt på grund av väder eller mycket grönska.
Som ett examensarbete vid Lunds Tekniska Högskola i samarbete med RISE och Väderstad har en prototyp för frökartläggning utvecklats. I jämförelse med liknande GPS-system är detta systemet utvecklat för konventionella såmaskiner. Ett system som lantbrukare snabbt kan adoptera utan förlust av effektivitet till skillnad från dagens GPS-robotar. Systemet i fråga förväntas kunna användas på alla Väderstads precisionsmaskiner med arbetsbredd på upp till 12 m i 15 km/h, där liknande system idag ligger på runt 2 m i 1 km/h.
Hjärtat av systemet är en mikrokontroller som hämtar data från en RTK-GPS och fröräknaren på såmaskinen. All data sparas sedan till ett SD-kort för analys i efterhand.
Två källor som antogs bidra till det totala felet i positioneringen var variation i frönas falltid från fröräknaren ned till marken, och variation hos GPS:en. Det visade sig att ett högre såhustryck ledde till snabbare frön, och att olika grödor var olika snabba. Beroende på dessa faktorer samt drifthastighet kunde variationen i fröfalltid innebära 2–20 mm i standardavvikelse på marken. Standardavvikelsen på GPS:ens rapporterade koordinater var 4–5 mm.
Fältförsök utfördes maj 2023 i Borgeby där majs och spannmål såddes med systemet igång. Efter detta lokaliserades och positionerades fröna i en kombination av manuell och RTK-GPS mätning. Det längdmässiga avståndet i såfårans riktning mellan de registrerade och faktiska fröpositionerna noterades. Resultatet blev att positionerna rapporterade av systemet utvecklat i detta arbete var inom 62,34 mm av ett frö 95% av gångerna. Systemet framtaget av studenterna på Lunds Tekniska Högskola resulterade i en prototyp som visade på en klar möjlighet till integrering av GPSsystem för frökartläggning i konventionella såmaskiner. Prototypen visar även på att systemet redan kan vara praktiskt vid till exempel majs och betodling. Arbetet har även gett en tydlig inblick inom förbättringsmöjligheter och hur målet för frökartläggning av enskilda spannmålsfrön för konventionellt lantbruk ska uppnås innan 2030. (Less)
Please use this url to cite or link to this publication:
http://lup.lub.lu.se/student-papers/record/9130027
- author
- Wikfeldt, Oskar LU and Pålsson Andersson, Christoffer LU
- supervisor
- organization
- course
- EIEM01 20231
- year
- 2023
- type
- H3 - Professional qualifications (4 Years - )
- subject
- keywords
- Agriculture, Individual plant care, RTK, GPS, GNSS, Geo-referencing, Seed mapping
- publication/series
- CODEN:LUTEDX/TEIE
- report number
- 5496
- language
- Swedish
- id
- 9130027
- date added to LUP
- 2023-08-17 09:42:45
- date last changed
- 2023-08-17 09:42:45
@misc{9130027,
abstract = {{With higher demands on farmers to reduce the usage of fertilizers and pes ti cides because of their negative environmental impact, as well as the rising prices of resources required for agriculture, precision agriculture has become a big focus in today’s agriculture research. Individual plant care systems are a big part of precision agriculture, and accurate information about the po si tions of individual plants is required for these systems. In collaboration with RISE Research Institutes of Sweden and Väderstad AB, a seed mapping system for the planter Väderstad Tempo was developed. The system was designed to determine the individual seed positions by receiving geographical coordinates from a real time kinematic global positioning system (RTK-GPS) in con junc tion with signals from the seed sensor already installed on the planter. A sec on dary task in the project was to isolate the error sources which would af fect the final error of the positioning. Variation in the GPS system’s reported coordinates as well as variation in the seed fall time from the seed sensor to the ground were investigated.
Seed fall times were measured in laboratory conditions where the type of crop, air pressure in the seed housing, and angular velocity of the seed disc were varied in order to build a mathematical model of the seed fall time. The de via tion metric root mean squared error (RMSE) of maize, sunflower, sugar beet, and cereal were 2.97 ms, 4.58 ms, 1.72 ms and 3.23 ms respectively.
Measurement of the variation of the RTK-GPS system was conducted in conjunction with the final tests of the system in a field. On average, the latitude and longitude had a RMSE of 4.17e-8 degrees and 6.38e-8 degrees respectively, which corresponded to a RMSE of 4.6 mm northing and 4.0 mm easting at the specific location of the measurements.
The seed mapping system was tested in a field under operation velocities in the range 5-15 km/h with the crops maize and cereal. After the seed mapping process, the seeds were found and positioned in a combination of RTK-GPS and manual measuring in order to determine their actual position. In the planter's driving direction, it was found that a seed could be found within a distance of 62.34 mm of a mapped seed position with a 95% probability.
The errors investigated for the seed fall times and RTK-GPS measurements turned out to only account for a small part of the total error of the seed mapping system. The remaining error stems from other parts of the process and needs to be investigated further.}},
author = {{Wikfeldt, Oskar and Pålsson Andersson, Christoffer}},
language = {{swe}},
note = {{Student Paper}},
series = {{CODEN:LUTEDX/TEIE}},
title = {{Noggrannhet av RTK-GPS-positionering av enskilda frön vid precisionssådd}},
year = {{2023}},
}