Robotics has been introduced in industry to replace humans in arduous and repetitive tasks, to reduce labour costs and to ensure consistent quality control of the process. Nowadays robots are cheaper, can work in hostile and dirty environments and they are able to manipulate products at high speed. High speed and reliability and low robot gripper costs are necessary for a profitable pick and place (P&P) process. However, current grippers are not able to handle these products properly because they have uneven shapes, are flexible and irregular, have different textures and are very sensitive to being damaged. This review brings together the requirements and phases used in the process of manipulation, summarises and analyses of the existing, potential and emerging techniques and their possibilities for the manipulation of fresh horticultural products from a detailed study of their characteristics. It considers the difficulties and the lack of engineers to conceive of and implement solutions. Contact grippers with underactuated mechanism and suction cups could be a promising approach for the manipulation of fresh fruit and vegetables. Ongoing study is still necessary on the characteristics and handling requirements of fresh fruit and vegetables in order to design grippers which are suitable for correct manipulation, at high speed, in profitable P&P processes for industrial applications.Additional key words: food manipulation; horticulture grasp; postharvest science and technology; robotic product handling. ResumenRevisión. Tecnologías en garras robotizadas para operaciones de coger y dejar productos hortofrutícolas frescos La robótica ha sido introducida en la industria para reemplazar a los humanos en tareas arduas y repetitivas, reducir mano de obra y para asegurar una calidad constante de los procesos. Actualmente los robos son más baratos, capaces de manipular productos a alta velocidad y de trabajar en ambientes hostiles. Por tanto, los robots pueden trabajar en operaciones de "coger y dejar" (pick & place, P&P) con frutas y hortalizas frescas. Para un proceso rentable de P&P, son necesarias una alta velocidad y fiabilidad, así como un bajo coste de los sistemas de agarre. Este artículo de revisión recopila las necesidades y fases empleadas en el proceso de manipulación, reuniendo y analizando las técnicas existentes, potenciales y emergentes y sus posibilidades de aplicación para la manipulación de productos hortofrutícolas frescos a partir del estudio detallado de sus características. Considera las dificultades y la falta de ingenieros para concebir e implementar soluciones. Los autores proponen las alternativas más prometedoras para acometer este difícil problema y consideran la necesidad de seguir estudiando las características de frutas y vegetales frescos y las necesidades de manipulación. Las garras de contacto con mecanismos infra-actuados y ventosas o agarrar el producto sin contacto pueden ser las alternativas más prometedoras para manipular frutas y vegetales frescos. Es necesario continuar e...
Conventional pneumatic grippers are widely used in industrial pick and place robot processes for rigid objects. They are simple, robust and fast, but their design, motion and features are limited, and they do not fulfil the final purpose. Food products have a wide variety of shapes and textures and are susceptible to damaged. Robot grippers for food handling should adapt to this wide range of dimensions and must be fast, cheap, reasonably reliable, and with cheap and reasonable maintenance costs. They should not damage the product and must meet hygienic conditions. The additive manufacturing (AM) process is able to manufacture parts without significant restrictions, and is Polyamide approved as food contact material by FDA. This paper presents that, taking the best of plastic flexibility, AM allows the implementation of novel actuators, original compliant mechanisms and practical grippers that are cheap, light, fast, small and easily adaptable to specific food products. However, if they are not carefully designed, the results can present problems, such as permanent deformations, low deformation limits, and low operation speed. We present possible solutions for the use of AM to design proper robot grippers for food handling. Some successful results, such as AM actuators based on deformable air chambers, AM compliant mechanisms, and grippers developed in a single part will be introduced and discussed.
ElsevierBlanes Campos, C.; Ortiz Sánchez, MC.; Mellado Arteche, M.; Beltrán Beltrán, P. (2015). Assessment of eggplant firmness with accelerometers on a pneumatic robot gripper. Computers and Electronics in Agriculture. 113:44-50. doi:10.1016/j.compag.2015 on the same day with the robot gripper, during the pick-and-place operation, and with a destructive firmness tester. The non-destructive parameters extracted from the gripper finger accelerometers were used to build and validate a partial least square model, with a calibration regression coefficient of r = 0.87 and a high prediction performance (r = 0.90). Furthermore, from the results of the paper, it has been seen that the procedure can be simplified by using only two non-destructive impacts and one uniaxial accelerometer to assess eggplant firmness. The non-destructive assessment of firmness while grasping agricultural products in pick-and-place operations could be implemented in many prehensile pneumatic robot grippers. This technique could mean an important advance in the hygienic postharvest handling of fruits and vegetables.
The objective of the study was to evaluate the use of a robot gripper in the assessment of mango (cv. BOsteen^) firmness as well as to establish relationships between the nondestructive robot gripper measurements with embedded accelerometers in the fingers and the ripeness of mango fruit. Intact mango fruit was handled and manipulated by the robot gripper, and the major physicochemical properties related with their ripening index were analyzed. Partial least square regression models (PLS) were developed to explain these properties according to the variables extracted from the accelerometer signals. Correlation coefficients of 0.925, 0.892, 0.893, and 0.937 with a root-mean-square error of prediction of 2.524 N/ mm, 1.579°Brix, 3.187, and 0.517, were obtained for the prediction of fruit mechanical firmness, total soluble solids, flesh luminosity, and ripening index, respectively. This research showed that it is possible to assess mango firmness and ripeness during handling with a robot gripper.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.