The 6-DOF Stewart parallel elevation platform serves as the platform for mounting the tea-picking robotic arm, significantly impacting the operational scope, velocity, and harvesting precision of the ...robotic arm. Utilizing the Stewart setup, a parallel elevation platform with automated lifting and leveling capabilities was devised, ensuring precise halts at designated elevations for seamless harvesting operations. The effectiveness of the platform parameter configuration and the reasonableness of the posture changes were verified. Firstly, the planting mode and growth characteristics of Yunnan large-leaf tea trees were analyzed to determine the preset path, posture changes, and mechanism stroke of the Stewart parallel lifting platform, thereby determining the basic design specifications of the platform. Secondly, a 3D model was established using SolidWorks, a robust adaptive PD control model was built using MATLAB for simulation, and dynamic calculations were carried out through data interaction in Simulink and ADAMS. Finally, the rationality of the lifting platform design requirements was determined based on simulation data, a 6-DOF Stewart parallel lifting platform was manufactured, and a motion control system was built for experimental verification according to the design specifications and simulation data. The results showed that the maximum deviation angle around the X, Y, and Z axes was 10°, the maximum lifting distance was 15 cm, the maximum load capacity was 60 kg, the platform response error was within ±0.1 mm, and the stable motion characteristics reached below the millimeter level, which can meet the requirements of automated operation of the auxiliary picking robotic arm.
The article considers the issue of designing at an early stage electromechanical drive of the lifting platform, which is a set of asynchronous frequency-controlled electric motor, two-stage involute ...bevel gear and lever mechanism scissor type. At the preliminary stage of designing the electromechanical drive of the lifting platform, its structure, types of engines and mechanisms included in it, as well as the main technical characteristics of the drive were determined. In particular, we determined the parameters of the linkage (geometric and mass-inertial characteristics), gear reducer (geometrical parameters, modules, numbers of teeth, gear ratio), carried out the choice of motor, calculation is made of kinematical and power characteristics, as well as dynamic study of the drive. The preliminary design was carried out using the Mechanic program, which does not require significant resources of a personal computer. As a result of the pre-design study, a schematic and structural solution of the lifting platform and electromechanical drive was formed, and their main technical characteristics were determined. As a result, it was proved that the use of the Mechanic program can be effectively applied at the initial stages of the design of the lifting platform, as well as various lifting and transport mechanisms and machines.
Makaslı platformlar sahip oldukları basit mekanik yapısı ve üretim kolaylığı sebebiyle endüstride yaygın olarak kullanılmaktadır. Platform için gerek duyulan hidrolik kuvvet ve platformun yükselme ...süresi, tasarımda önemli faktörler arasında yer almaktadır. Bu çalışmada, platformun uzuv boyu, hidrolik silindirin mafsal konumları ve hidrolik hızı değişken parametreler olarak seçilmiştir. Parametreler için öngörülen farklı değerlerin platformun yükselme süresine ve platformda ihtiyaç duyulan hidrolik kuvvetine etkileri incelenmiştir. Ayrıca, parametre seçimlerinde hidrolik silindirin maksimum strok değeri bir tasarım sınırı olarak dikkate alınmıştır. Hidrolik kuvvet ifadesi hem Virtüel İşler Prensibi (VİP) hem de Virtüel Güçler Prensibi (VGP) ile elde edilerek statik ve dinamik hesaplar arasında oluşan farklar belirlenmiştir. Simülasyonlar sonucunda, farklı tasarım ölçüleri ve hidrolik hızları ile elde edilen sonuçlar karşılaştırılarak yükselme süresini ve hidrolik kuvveti minimize etmek için uygun geometri belirlenmiştir.
Scissor lifting platforms are widely used in industry due to their simple mechanical structure and ease of production. The hydraulic force required for the platform and the rise time of the platform are among the important factors in the design. In this study, the length of the scissor arms, the joint positions of the hydraulic cylinder and the hydraulic speed were chosen as variable parameters. The effects of different values assigned to the parameters on the rise time of the platform and the hydraulic force required on the platform were investigated. In addition, the maximum stroke value of the hydraulic cylinder is considered as a design limit in parameter selections. The hydraulic force expression was obtained with both the Virtual Works Principle (VWP) and the Virtual Power Principle (VPP). Differences between static and dynamic calculations have been determined. Thus, by comparing the results obtained with different design dimensions and hydraulic speeds, the appropriate geometry was determined to minimize the rise time and hydraulic force.
The paper analyzes the service process of proposed multi-automated garage with a capacity of approximately 1000 parking spaces. By using specific construction techniques this solution is competitive ...to other solutions implemented in many places of the world. The paper also contains a short review of existing solutions and shows the additional value provided from the proposed garage concept. Queuing theory was used to describe the service process (transport of vehicles) from the points of input into to output from the garage. In this case, the automatic garage was treated as a complex system of mass service (queuing system). The general advantage of the proposed solution is the possibility of parallel service of 10 vehicles by using only one lift (resulting in savings of place and time). At the end of the paper, proposals for further work are also described.
•Operation of garage transport systems•Operation time of receiving, parking and returning cars•Description of the queuing system for a garage story•Queuing theory usage to evaluate the efficiency of the operation of the garage
Elevating work platforms are hoists equipment that are increasingly used in many applications, like in the construction industry and in the maintenance field. The maintenance of the hub of the wind ...turbines, for example, can be done through the use of a working platform; these structures have to reach great heights and obviously they have to satisfy the constraints induced by the highway standards, like the maximum axle load and the maximum overall dimensions. To satisfy these requests the material of the structures changed from the classic structural steel (S235 JR, S275 JR or S355JR) to high strength steel (S700 to S1100 or more), characterized by a significantly higher specific resistance. The idea of this paper is to use a composite material for the construction of the arms of an elevating platform in order to reduce the global weight of the machine. The analyses on the new kind of platform show the technical possibility to change the material of the arms with composite materials and this produces a significant reduction of the weight of the machine components, about 50 %. Being a feasibility study, still remain open some problems such as the mechanical behavior of the used composite materials (fatigue, environment effects, etc.).
The design for ordinary garage aims at its small and its insufficient space of goods storage of the flaws and even only a private car can be parked. We adopted the bold structure innovation and ...designed the Dual Power mechanical simple garage lifting platform. And the device is simple in structure and easy in manufacture with high stability. And goods of storage is convenient which one can take it when wants to use. And two cars can been parked in the auto conditions permitting. Thus it can make the ordinary garage maximize the use of space and improve the utilization of space resources.
This paper put forward a systematic design method based on virtual prototyping technology to simulate lifting platform of jacking system in jack-up offshore platform. After the main parameters of ...lifting platform in jack-up offshore platform were introduced, the 800T offshore platform modeling techniques were put forward, such as rigid body modeling techniques, flexible body modeling techniques, modal analysis techniques and kinematics analysis. The dynamics analysis was present with the simulation results, which demonstrates that this method is obviously helpful to get more accurate simulation results to verify the rationality of lifting platform in jack-up offshore platform.
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