Journal of the ASABE最新文献

{"title":"Testing the Agreement Between a Traditional and UAV-Based Method for Quantifying Skips in Suboptimal Cotton Stands","authors":"Enrique Eduardo Pena Martinez, J. Ward, G. Collins, Natalie Nelson","doi":"10.13031/ja.14760","DOIUrl":"https://doi.org/10.13031/ja.14760","url":null,"abstract":"Highlights Agreement in the mean difference between the traditional and the UAV-based method only occurred in poor stands. Effects of different sampling sizes between methods were evident in mediocre-to-good stand assessments. Abstract. When suboptimal cotton stands occur, growers face the decision to accept or reject the stand. The replanting decision is difficult because the tradeoffs associated with replanting expenditures and reduced yields are difficult to objectively assess. Traditional methods like visual assessments and manual counts of cotton stands are commonly used to support a replanting decision. Typically, manual counts of skip size and frequency will provide more accurate assessments of the stand than visual assessments, but they are cumbersome to conduct and may not provide clear evidence that a replant is needed. Still, manual counts are popular among cotton farmers and the scientific community. Skip counts generated with the help of unmanned aerial vehicles (UAV) are less popular among cotton growers but provide more coverage and a larger sampling size across a given field. Therefore, UAVs have the potential to overcome the limitations associated with traditional methods. The motivation behind this study is to inform readers if manual methods can still be used for accurate decision-making regarding the replanting decision. More specifically, we study the interchangeability, or agreement, between a manual and a UAV-based method using Bland-Altman plots. Each method quantified skips greater than or equal to 0.91 m at different sampling sizes. Treatment plots varied in their stand counts, skip size, and skip frequency. Agreement between both methods was only found in the lowest stand treatment, where skips of large sizes were predominant. Conversely, methods disagreed in the higher stand where skips greater than or equal to 0.91 m were scarce. Keywords: Agriculture, Altman, Bland, Drone, Gaps, Precision, Remote, Sensing, UAS.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"21 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80368299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sweet Sorghum And Sweet Pearl Millet Carbohydrate Extraction and Preservation for Bioethanol Production and Bagasse Valorization: A Review","authors":"Noura Saïed, M. Khelifi, A. Bertrand, M. Aider","doi":"10.13031/ja.15211","DOIUrl":"https://doi.org/10.13031/ja.15211","url":null,"abstract":"Highlights Sweet sorghum and sweet pearl millet are interesting feedstocks for ethanol production. Biomass and juice storage are key steps for carbohydrate preservation. Produced bagasse can be valorized in many ways, including as silage or for cellulosic ethanol production. Abstract. Sweet sorghum and sweet pearl millet have been considered as potential energy crops. They have many advantages in terms of ethanol production compared to corn and sugarcane, such as lower requirements for water and fertilizers, higher tolerance to drought, and lower competition with the food sector. Sweet sorghum and sweet pearl millet stems are rich in water-soluble carbohydrates (WSC) (sucrose, fructose, and glucose), and their biomass has to be crushed for juice extraction. However, the extraction efficiency of WSC varied widely depending on the press type used and the parameters considered during the pressing process (stripping stems from leaves or not, compressive force magnitude, smooth or grooved press rollers, number of times of biomass pressing, etc.). WSCs are easily degradable, causing technical challenges related to crop handling before pressing and juice storage thereafter. Some studies focused on stem preserving methods, whereas others dealt with extending the shelf life of the juice. To make the use of sweet sorghum and sweet pearl millet as energy crops more profitable, the bagasse (residue) generated from biomass pressing can be valorized in different ways, mainly as silage or for second generation ethanol production. The objective of this review was to assess the efficiency of different presses used for juice extraction and discuss various methods tested for WSC conservation from deterioration as well as possible bagasse valorization. Keywords: Bagasse, Carbohydrates, Ethanol, Press, Sweet pearl millet, Sweet sorghum.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89442934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Calculation of Swath Width and Swath Displacement for Uncrewed Aerial Spray Systems","authors":"J. Bonds, B. Fritz, H. Thistle","doi":"10.13031/ja.15400","DOIUrl":"https://doi.org/10.13031/ja.15400","url":null,"abstract":"Highlights Recent research has focused on the use of Uncrewed Aerial Spray Systems (UASS) for their potential to fill the gap between crewed aircraft and ground application equipment. The spray distribution in swath is highly variable to the point that using the typical metric of uniformity alone to define swath can no longer apply, we present a method that considers dose and uniformity. The swath was rarely found to be directly beneath the flightline, the swath displacement and offsetting can be significant and larger than the assumed swath width. This paper presents the development of an evidence-based, repeatable mathematical solution to the determination of swath width and swath displacement for UASS for calibration and targeting purposes. Abstract. Recent research has focused on the use of Uncrewed Aerial Spray Systems (UASS) for their potential to fill the gap between crewed aircraft and ground application, with UASS being able to be used over less accessible areas than ground equipment, being more appropriate to treat smaller, dispersed targets, and typically available at reduced cost and complexity when compared to crewed aircraft. However, there is limited literature focusing on the proper setup and use of these systems. The objective of this study was to design and conduct a series of large-scale, conceptually linked studies to provide data that is used to guide system optimization and the development of predictive models. An uncrewed system coupled with three nozzle types covering three droplet size classifications was used to conduct swath characterization and drift trials designed to establish effective swath widths, deposition variability, swath displacement, and drift. System and nozzle type, along with nozzle position and wind direction, significantly impacted the spray deposition patterns within and downwind of the effective swath. The spray distribution in a swath is highly variable, to the point that using the typical metric of uniformity alone to define swath can no longer apply. In addition, the swath was rarely found to be directly beneath the flightline, and swath offsetting can be significant and larger than the assumed swath width. An iterative solution has been developed that uses a combination of effective dose and uniformity to define swath width. The offsetting of the swath due to interactions with ambient air has also been defined using the Center of Deposition. The aim is to be able to distinguish between in-swath deposition and drift. The approach to defining swath width and the displacement of the swath is presented. The goal is to develop a real-time onboard navigation system that can reset the flight line in response to wind-driven swath displacement. This allows increased deposition within the target zone and reduces off-target losses. Keywords: Aerial application, Offset, Swath displacement, Swath width, Unmanned aerial spray system.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72763542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Batch Process Operational Effects on Phosphorus Attainment in Hydrochar Produced by Hydrothermal Carbonization of Dairy Manure","authors":"B. He","doi":"10.13031/ja.15194","DOIUrl":"https://doi.org/10.13031/ja.15194","url":null,"abstract":"Highlights Temperature ramp-up from 180°C to the pre-set processing temperature significantly affects total phosphorus attainment rate. The transition time of temperature ramp-up is crucial in assessing the change of TP attainment rate. Temperature cooling does not show significant effect on total phosphorus attainment rate. Abstract. As an alternative technology for phosphorus cycling, hydrochar produced from animal manure is a great vehicle to attain phosphorus from dairy manure and apply it back to cropland in an environmentally friendly manner. Hydrochar production by hydrothermal carbonization (HTC) greatly reduces the time to manage animal manure compared to traditional lagoon systems. Before being established as a practical technology for hydrochar production in continuous-flow operations, HTC in batch mode is the best way to systematically investigate and optimize the process conditions for high efficiencies. This study investigates specifically the effect of temperature ramp-up rates on the attainment of total phosphorus (TP) in hydrochar produced from dairy manure through batch-mode HTC operations. Experimental results revealed that the transition in temperature ramp-up greatly affected the TP attainment rate in hydrochar, depending on the pre-set processing temperatures and holding time. Statistical analysis confirms that such an effect is significant if the holding time is 30 min or less. This is due not only to the higher processing temperatures but also to the extra 5 to 15 minutes of processing time required for the ramp-up to the pre-set temperatures of 195°C to 255°C, at which point biomass decomposition has already occurred. It is concluded that the temperature ramp-up in batch HTC processes significantly affect the TP attainment rate in hydrochar produced from dairy manure. Before developing continuous-flow HTC systems, it is recommended that experimental results from batch operations be carefully interpreted. Keywords: Batch processes, Dairy manure, Hydrochar, Hydrothermal carbonization, Phosphorus.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88901311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"X-ray Imaging Assessment of Internal Seed Morphology as a Nondestructive Viability Prediction for Triploid Watermelon Seeds","authors":"Suk-Ju Hong, Ahyeong Lee, Sang-Yeon Kim, EungChan Kim, Jiwon Ryu, Dae Young Kim, Ghiseok Kim","doi":"10.13031/ja.15563","DOIUrl":"https://doi.org/10.13031/ja.15563","url":null,"abstract":"Highlights X-ray imaging techniques were used to assess the internal morphology of triploid watermelon seeds. Structural integrity of triploid watermelon seed was quantified through image-processing and analyzed according to multiple viability classes. Integrity and CNN-based viability prediction models were developed and evaluated for multiple viability criteria. In the integrity analysis and modeling results, there were differences in the correlation between internal seed morphology and viability depending on the condition of the seed lot. Abstract. Watermelon (Citrullus lanatus) is a tropical fruit consumed worldwide in various forms. Triploid watermelons—or seedless watermelons—have remained popular for decades because of the absence of hard seeds and their flavor. However, triploid watermelon seeds have lower viability than diploid watermelon seeds because of their thick seed coats, underdeveloped embryos, and larger internal cavity spaces. This poor viability characteristic of triploid watermelon seed leads to low crop productivity. Therefore, a nondestructive inspection technology is deemed necessary for sorting triploid watermelon seeds. In this study, we assessed the internal morphology of triploid watermelon seeds by applying the X-ray imaging technique to predict seed viability. More specifically, we analyzed the association between the structural integrity and viability of the seeds by X-ray image processing. Furthermore, prediction models based on integrity and convolutional neural networks (CNN) were developed and evaluated for multiple viability criteria and seed lots. As a result, first-grade class seeds were shown to significantly differ from the rest of the classes in terms of integrity. Similarly, the performance of classifying the first-grade class from other classes was the highest among classification criteria in prediction models. Although the CNN model showed better performances than the integrity-based model, seed integrity was considered to be the most important feature even in the CNN model. The CNN model in this study showed accuracies of 73.64%–90.63% depending on the seed lot, suggesting that the correlation between seed internal structure and viability may differ depending on the conditions of the seed lot. Keywords: Deep learning, Seed, Seed integrity, Triploid watermelon, Viability, X-ray.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135600987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Magnitude of External Phosphorus Loading Likely Reduces Effectiveness of Aluminum Sulfate Treatments for Management of Sediment Phosphorus Flux","authors":"A. Lasater, B. Haggard, J. A. Lee","doi":"10.13031/ja.15284","DOIUrl":"https://doi.org/10.13031/ja.15284","url":null,"abstract":"Highlights Phosphorus fluxes were quantified before and after alum treatments five times between 2014 and 2019. Phosphorus fluxes were not significantly different from baseline after five treatments spread over six years. Long-term effectiveness of alum treatments was reduced due to large external phosphorus loads. Abstract. This study quantified sediment P fluxes under aerobic and anaerobic conditions at Quarry Island Cove at Lake Wister, Oklahoma, before and after alum treatments, which occurred five times between 2014 and 2019. Sediment-water cores were collected from the cove and incubated for 10 days at room temperature under aerobic and anaerobic conditions, and P fluxes were estimated as the slope of the increase in P mass over time divided by the area of the core. Aerobic P fluxes were not significantly different before or after alum treatments. Under anaerobic conditions, P fluxes significantly decreased one week after alum treatments compared to a week before treatment. However, after five treatments across six years, sediment P fluxes under anaerobic conditions were not significantly different than prior to any alum treatments in 2010 and 2014 (3 to 4 mg m-2 day-1). The lack of overall improvement in anaerobic P fluxes over time is likely due to the magnitude of P and sediment loads entering Lake Wister from the watershed, where 92% of the total P load to Lake Wister from 2010 to 2020 was from external sources. Therefore, while alum treatments provide short-term reductions in P fluxes, external P sources must be addressed. Keywords: Aluminum sulfate, Lake management, Nutrient loads, Phosphorus.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74619016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Equine Kinematic Gait Analysis Using Stereo Videography and Deep Learning: Stride Length and Stance Duration Estimation","authors":"Nariman Niknejad, Jessica L. Caro, Rafael Bidese-Puhl, Y. Bao, E. Staiger","doi":"10.13031/ja.15386","DOIUrl":"https://doi.org/10.13031/ja.15386","url":null,"abstract":"Highlights Stereo machine vision and deep learning techniques were investigated for infield equine kinematic gait analysis. The proposed pipeline tracks equine body landmarks in 3D space and estimates stride length and stance duration. The system can serve as a cost-effective, rapid, and easy-to-use tool for equine locomotion research. Abstract. Equine kinematic gait analysis (EKGA) currently requires a complicated, expensive, and labor-intensive procedure for equine locomotion research. An automated stereo video processing pipeline was developed and evaluated for measuring equine biomechanical parameters. Using stereo videos of 40 different walking horses, a DeepLabCut (DLC) model was trained to detect body landmarks in individual frames. With an autoregressive integrated moving average filter, the landmark detection had a root mean square error of 5.14 pixels and a mean absolute error of 4.87 pixels. As a case study, methods were developed to extract stride length (SL) and stance duration (SD). Individual hoof gait phase detection was achieved using a fine-tuned Faster R-CNN model and a mode filter, yielding precision and recall values of 0.83 and 0.95, respectively. The semi-global block matching (SGBM) algorithm was used to estimate depth maps, and the accuracy was assessed by comparing head length estimation with infield measurements. A Bland-Altman analysis for DLC-detected head length in combination with SGBM-based 3D reconstruction yielded a bias of -0.014 m with upper and lower limits of agreement (LoAs) of 0.03 m and -0.061 m, respectively. Furthermore, Bland-Altman analyses on SD and SL when compared to image-level manual measurements showed biases of -0.02 sec and -0.042 m, respectively. The corresponding LoAs were (0.01907 sec, -0.24 sec) for SD and (0.04 m, -0.12 m) for SL. The proposed method showed promising potential in performing EKGA in an automated, cost-effective, and rapid manner under field conditions. Keywords: 3D Reconstruction, Animal Pose Estimation, Deep Learning, Equine Kinematic Gait Analysis, Stereo Matching.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"44 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90721627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Applicability and Sensitivity of Field Hydrology Modeling by the Soil Plant Air Water (SPAW) Model Under Changes in Soil Properties","authors":"A. Saha, John McMaine","doi":"10.13031/ja.15306","DOIUrl":"https://doi.org/10.13031/ja.15306","url":null,"abstract":"Highlights Changes to soil properties and precipitation scenarios significantly affect the water balance in agro-hydrology. SPAW model is sensitive to simulated runoff and infiltration, but it has limitations in responding to soil compaction and organic matter change. Increasing organic matter (1% to 5%) did not significantly affect runoff or infiltration in silty and sandy loam soil. Low precipitation generates significantly lower runoff (%) and higher infiltration. Abstract. Agricultural practices can change soil properties and the amount of runoff generated from a landscape. Modeling results could be significantly different than expected if the web soil survey or other commonly used remote sensing applications are used as model inputs without site verification. This study assessed the applicability and sensitivity of the Soil-Plant-Air-Water (SPAW) Model for simulating the runoff (%) and infiltration (%) components of the water balance for various soil physical properties, cover crop, and weather variables. Soil profiles in 135 combinations were developed with three soil classes (sandy loam, silt loam, and clay), five organic matter levels (1%, 2%, 3%, 4%, and 5%), three levels of compaction (low, medium, and high), and three topsoil layer thicknesses (7.6 cm, 11.4 cm, and 15 cm). Also, three cover crop treatments were simulated by modifying surface cover and evapotranspiration during the non-growing season. Finally, two precipitation regimes were considered (Iowa City, IA, as high precipitation and Brookings, SD, as low precipitation) to simulate runoff and infiltration. In total, 810 scenarios were run, resulting in over 300 million data points. This study confirmed that soil texture, bulk density, and topsoil thickness significantly (p<0.01) influence runoff generation and infiltration percentage based on the water balance criterion. Interestingly, the SPAW model had no significant response on runoff (%) and infiltration (%) to organic matter levels changing from 1% to 5%. This simulation demonstrates that runoff estimations can be significantly influenced by soil properties that can change due to agricultural conservation practices (ACPs) or, conversely, by compaction events. Inputs to models must account for these changes rather than relying only on historical or remote sensing inputs. Keywords: Agricultural conservation practices, Conservation agriculture, Field hydrology, Infiltration, Runoff, SPAW.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"22 6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85057717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Co-Harvest and Anaerobic Co-Storage of Corn Grain and Stover as Biomass Feedstocks","authors":"","doi":"10.13031/ja.15299","DOIUrl":"https://doi.org/10.13031/ja.15299","url":null,"abstract":"Highlights Cutting height and harvest date were used to alter stover moisture content, yield, and composition. Anaerobic co-storage of grain and stover limited losses to less than 6% of dry matter. Extent of fermentation was greater for higher moisture stover than grain, but total acids were less than 5 g kg-1. Reducing the harvester cutter head rotational speed resulted in a greater fraction of whole corn kernels. Abstract. This research investigated the utility of co-harvesting and anaerobic co-storage of corn grain and stover to positively influence their physical and chemical characteristics as a biomass feedstock. Corn grain and stover were harvested in 2019 and 2020 with a self-propelled forage harvester. Stover yield, moisture content, and composition were altered by the harvest date, stubble height, and header configuration. Harvest date had the utility of varying the stover moisture content (p < 0.001) from 42.3% to 53.5% (w.b.) and 43.1% to 53.9% (w.b.) for the 2019 and 2020 harvest years, respectively. Stubble height was also utilized to vary stover moisture content. A negative linear relationship was established between stubble height and stover moisture content for the early (R2 = 0.76) and late harvest (R2 = 0.91) dates for both years. Stover yield also showed a negative linear relationship (R2 = 0.76) with stubble height over both years. Regardless of the stubble height, the row-crop header collected more stover (p < 0.001) than the ear-snapper header. In 2020, harvested stover ranged from 5.0 to 10.5 Mg ha-1, with ha-1 representing 41% to 85% of the total available stover. In both years, stover ash content was less than 64 g kg-1. Material stored in pilot-scale silos (19 L) was well conserved during anaerobic storage, with average DM losses of 4.8% and 3.4% in 2019 and 2020, respectively. Grain moisture content averaged 23.6% (w.b.) at harvest, and 31.0% (w.b.) after storage as moisture migrated from the moist stover to the drier grain. Harvesting whole-plant corn with a forage harvester had the unwanted effect of reducing the particle size of the grain fraction, which would complicate downstream utilization. However, reducing the harvester cutterhead speed increased the fraction of intact kernels from 47% to 85% by mass. The studied system was a viable alternative to conventional corn grain and stover systems for producing feedstocks for biochemical conversion. Keywords: Ash, Ensiling, Ethanol, Maize.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"144 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82927818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stereo Vision Controlled Variable Rate Sprayer for Specialty Crops: Part II. Sprayer Development and Performance Evaluation","authors":"Carla Román, H. Jeon, Heping Zhu, Javier Campos, E. Ozkan","doi":"10.13031/ja.15578","DOIUrl":"https://doi.org/10.13031/ja.15578","url":null,"abstract":"Highlights A real time stereo vision controlled variable rate sprayer for specialty crops was developed. The stereo vision system of the sprayer detected outdoor trees with similar canopy profiles under travel speeds ranging from 3.2 to 8 km h-1. Canopy volume measurements of the sprayer were impacted by lateral distances between the sprayer and the tree center and travel speeds. The sprayer required less than 200 ms from tree canopy detection to spray decisions. The sprayer achieved spray volume reductions from 72.6% to 80.5% compared to constant rate spray application. Abstract. A real time variable rate sprayer controlled by a stereo vision system was developed to increase the accuracy of spray applications and reduce the use of crop protection products. The sprayer was designed to detect tree canopies and calculate its volume using depth images from the stereo vision system, and discharge corresponding spray volumes every 200 ms through the embedded software in the graphical user interface. The sprayer was evaluated in an apple orchard at different travel speeds (3.2 to 8.0 km h-1) for its performance in detecting canopy and measuring its volume. In addition, spray volume, deposition, and coverage of the variable rate application of the sprayer were evaluated against a constant rate application. Test results showed that the sprayer detected visually similar tree canopies during the evaluations, although its canopy volume measurements deviated from manually measured canopy volume from 0.11 to 0.83 m3 due to lateral position changes of the sprayer. The sprayer adjusted duty cycles of pulse width modulated valves to accurately spray the intended volume for detected canopies (0.073 to 0.083 L m-3) and only used spray volumes of 19.5% to 26.7% compared to a constant rate spray application (338 L ha-1). The constant rate spray application generally had more spray deposition and coverage in tree canopies than the variable rate sprayer, as expected since its spray volume was approximately 3.7 times higher. However, the mean spray depositions from the constant rate spray application were significantly varied (p=0.05) by tree sizes, while the variable rate spray application achieved statistically equivalent mean spray depositions regardless of tree sizes. The stereo vision controlled sprayer offers a cost-effective real-time variable rate spray option for growers with the potential to perform other tasks by using image processing algorithms while applying crop protection products. Keywords: Automation, Canopy volume, Crop protection, Depth image, Orchard, Precision agriculture, Real-time application.","PeriodicalId":29714,"journal":{"name":"Journal of the ASABE","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81362888","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}