Design and Experiment of Symmetrical Shape Deployable Arc Profiling Mechanism Based on Composite Multi-Cam Structure

Abstract

At present, there are few reports on the profiling mechanism that can achieve surface envelope profiling along the surface of a shaft whose radius is constantly changing. Existing profiling mechanisms cannot achieve this function. To this end, a novel deployable arc profiling mechanism is presented in this paper. The mechanism can realize centering deployment along the shaft with a changing radius. The radius of the deployable arc can be adapted to the continuous change of shaft radius, and its surface can always maintain the arc shape for surface envelope profiling. The mechanism is mainly composed of compound cams. Each cam contains multiple grooves, and each groove connects to an arc support linkage. The arc support linkage is controlled by the compound motion of cams in different layers. The pitch curve of each groove is designed by applying the method of relative motion and inverse solution and obtained various parameter equations of the mechanism. The feasibility of this mechanism is verified by analysis, experiment, and application test. The results show that the proposed deployable arc profiling mechanism can achieve the design purpose and the profiling accuracy is kept above 96.425%.

Design and Experiment of Banana De-Handing Device Based on Symmetrical Shape Deployable Mechanism

“…Similarly, using such deployable units to manufacture a circular cutter with the same enveloped circular surface can effectively reduce the number of basic units. The surface coverage area of the deployed ring mechanism is similar to a circle, and the diameter D of the deployed round surface can be calculated by Equation (3). The folded height h and deployed height H are consistent, which is about three times of the length c of the short connecting rod, and named h = 3c.…”

“…The folded height h and deployed height H are consistent, which is about three times of the length c of the short connecting rod, and named h = 3c. Assuming that, when folded, the vertical rods are parallelly arranged in a circular manner, the diameter of the vertical rod is d', and each basic unit contains an average of six rods; hence, the maximum value of the ring diameter d can be approximately calculated as follows, The surface coverage area of the deployed ring mechanism is similar to a circle, and the diameter D of the deployed round surface can be calculated by Equation (3). The folded height h and deployed height H are consistent, which is about three times of the length c of the short connecting rod, and named h = 3c.…”

“…In order to solve the key technical problems such as the poor profiling ability and the low self-adaptive performance of the banana de-handing device in banana mechanical de-handing, and further to manufacture practical mechanical de-handing devices, Yang Zhou and Xu Zeyu explored two types of mechanical de-handing mechanisms for single banana hand de-handing based on the manual de-handing method. One of them is an impact insert-type banana de-handing mechanism with ring cutters [2], and the other is a vibration-cutting mechanism with arc cutters [3]. In the mechanical banana de-handing procedure, the whole banana bunch needs to be fixed vertically for convenience of de-handing.…”

Mechanized Technology Research and Equipment Application of Banana Post-Harvesting: A Review

“…The cutting mechanism of banana crown fiber during de-handing procedure was obtained, and the combined method of discrete element and finite element was used to numerically simulate the cutting procedure of banana crown fibers. After that, a profiling de-handing method based on the vibrated cutting mechanism was proposed, and a banana vibrated de-handing device based on the deployable mechanism was manufactured [77], as shown in Figure 8. The coupling movement formed by three flat sliders in the device can realize the arc mechanism deploying.…”

Research on the Physical Characteristic Parameters of Banana Bunches for the Design and Development of Postharvesting Machinery and Equipment

“…The dehanding operation generally relies on manual work, and the high-intensity and repetitive work brings huge health risks to the workers [6]. At present, the research on key technology and the design and manufacture of mechanical banana dehanding equipment are in the embryonic stage, and there is still a lot of room for improvement in the working performance of the mechanical mechanism [7][8][9]. The banana bunch stalk is not only rich in high-quality natural plant fibers but also a valuable biomass resource.…”