Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk
A method combining experimental and simulation optimization was used to calibrate parameters to enhance the accuracy of discrete element model parameters during kiwifruit stem separation. First, physical experiments were conducted to determine the intrinsic and contact parameters of kiwifruit stalk...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
PAGEPress Publications
2024-12-01
|
| Series: | Journal of Agricultural Engineering |
| Subjects: | |
| Online Access: | https://www.agroengineering.org/jae/article/view/1640 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850057120339197952 |
|---|---|
| author | Zhi He Xinting Ding Wei Hao Kai Li Weixin Gong Zixu Li Yongjie Cui |
| author_facet | Zhi He Xinting Ding Wei Hao Kai Li Weixin Gong Zixu Li Yongjie Cui |
| author_sort | Zhi He |
| collection | DOAJ |
| description |
A method combining experimental and simulation optimization was used to calibrate parameters to enhance the accuracy of discrete element model parameters during kiwifruit stem separation. First, physical experiments were conducted to determine the intrinsic and contact parameters of kiwifruit stalk. Second, the mechanical parameters of the kiwifruit stalks were determined using three-point bending and shear tests. On this basis, simulation tests were conducted on kiwifruit stalks by combining the Hertz-Mindlin model with a bonding model, and the optimal combination of bonding parameters was confirmed using the bending strength and maximum shear force. Finally, a discrete element model of the kiwifruit was built with the determined bonding parameters and simulated, and the reliability of the model was verified through mechanical tests. The results showed that the density was 867.5 kg/m3, Poisson's ratio was 0.26, the modulus of elasticity was 3.25 × 108 Pa, the recovery coefficient between the fruit stalks and steel parts was 0.365, and the average values of the static and dynamic friction coefficients between the kiwifruit stalks and steel parts were 0.268 and 0.152, respectively. The kiwifruit stem bonding parameters were normal stiffness per unit area kn=7.201×1011 N/m3, shear stiffness per unit area kt=2.379×1011 N/m3, critical normal stress σmax=5.937×108 Pa, critical shear stress tmax = 2.354×109 Pa, and bonded disc radius Rj=0.164 mm. Compared with the results of the mechanical tests, the relative errors of the bending strength and maximum shear of the discrete element model were 2.13% and 2.84%, respectively. The results showed that the discrete element model improves the simulation of the bending and shearing processes of kiwifruit stalks and is capable of characterizing the physical properties of kiwifruit stalks. The results of this study provide a theoretical foundation for the optimal design of end effectors.
|
| format | Article |
| id | doaj-art-d3128f3d84114dd58488633dbe9dc6c4 |
| institution | DOAJ |
| issn | 1974-7071 2239-6268 |
| language | English |
| publishDate | 2024-12-01 |
| publisher | PAGEPress Publications |
| record_format | Article |
| series | Journal of Agricultural Engineering |
| spelling | doaj-art-d3128f3d84114dd58488633dbe9dc6c42025-08-20T02:51:31ZengPAGEPress PublicationsJournal of Agricultural Engineering1974-70712239-62682024-12-0155410.4081/jae.2024.1640Calibration and experiments of discrete element flexible model parameters for kiwifruit stalkZhi He0Xinting Ding1Wei Hao2Kai Li3Weixin Gong4Zixu Li5Yongjie Cui6College of Mechanical and Electronic Engineering, Northwest A&F University, YanglingCollege of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; Key Laboratory of Agricultural Internet of Things, Ministry of Agriculture and Rural Affairs, Yangling, ShaanxiCollege of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service, Yangling, ShaanxiCollege of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service, Yangling, ShaanxiCollege of Mechanical and Electronic Engineering, Northwest A&F University, YanglingCollege of Mechanical and Electronic Engineering, Northwest A&F University, YanglingCollege of Mechanical and Electronic Engineering, Northwest A&F University, Yangling;Shaanxi Key Laboratory of Agricultural Information Perception and Intelligent Service, Yangling, Shaanxi A method combining experimental and simulation optimization was used to calibrate parameters to enhance the accuracy of discrete element model parameters during kiwifruit stem separation. First, physical experiments were conducted to determine the intrinsic and contact parameters of kiwifruit stalk. Second, the mechanical parameters of the kiwifruit stalks were determined using three-point bending and shear tests. On this basis, simulation tests were conducted on kiwifruit stalks by combining the Hertz-Mindlin model with a bonding model, and the optimal combination of bonding parameters was confirmed using the bending strength and maximum shear force. Finally, a discrete element model of the kiwifruit was built with the determined bonding parameters and simulated, and the reliability of the model was verified through mechanical tests. The results showed that the density was 867.5 kg/m3, Poisson's ratio was 0.26, the modulus of elasticity was 3.25 × 108 Pa, the recovery coefficient between the fruit stalks and steel parts was 0.365, and the average values of the static and dynamic friction coefficients between the kiwifruit stalks and steel parts were 0.268 and 0.152, respectively. The kiwifruit stem bonding parameters were normal stiffness per unit area kn=7.201×1011 N/m3, shear stiffness per unit area kt=2.379×1011 N/m3, critical normal stress σmax=5.937×108 Pa, critical shear stress tmax = 2.354×109 Pa, and bonded disc radius Rj=0.164 mm. Compared with the results of the mechanical tests, the relative errors of the bending strength and maximum shear of the discrete element model were 2.13% and 2.84%, respectively. The results showed that the discrete element model improves the simulation of the bending and shearing processes of kiwifruit stalks and is capable of characterizing the physical properties of kiwifruit stalks. The results of this study provide a theoretical foundation for the optimal design of end effectors. https://www.agroengineering.org/jae/article/view/1640Kiwifruit stalksdiscrete elementbonding modelparameter calibration |
| spellingShingle | Zhi He Xinting Ding Wei Hao Kai Li Weixin Gong Zixu Li Yongjie Cui Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk Journal of Agricultural Engineering Kiwifruit stalks discrete element bonding model parameter calibration |
| title | Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk |
| title_full | Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk |
| title_fullStr | Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk |
| title_full_unstemmed | Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk |
| title_short | Calibration and experiments of discrete element flexible model parameters for kiwifruit stalk |
| title_sort | calibration and experiments of discrete element flexible model parameters for kiwifruit stalk |
| topic | Kiwifruit stalks discrete element bonding model parameter calibration |
| url | https://www.agroengineering.org/jae/article/view/1640 |
| work_keys_str_mv | AT zhihe calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk AT xintingding calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk AT weihao calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk AT kaili calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk AT weixingong calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk AT zixuli calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk AT yongjiecui calibrationandexperimentsofdiscreteelementflexiblemodelparametersforkiwifruitstalk |