Spiral Complete Coverage Path Planning Based on Conformal Slit Mapping in Multi-connected Domains

Generating a smooth and shorter spiral complete coverage path in a multi-connected domain is an important research area in robotic cavity machining. Traditional spiral path planning methods in multi-connected domains involve a subregion division procedure; a deformed spiral path is incorporated within each subregion, and these paths within the subregions are interconnected with bridges. In intricate domains with abundant voids and irregular boundaries, the added subregion boundaries increase the path avoidance requirements. This results in excessive bridging and necessitates longer uneven-density spirals to achieve complete subregion coverage. Considering that conformal slit mapping can transform multi-connected regions into regular disks or annuluses without subregion division, this paper presents a novel spiral complete coverage path planning method by conformal slit mapping. Firstly, a slit mapping calculation technique is proposed for segmented cubic spline boundaries with corners. Then, a spiral path spacing control method is developed based on the maximum inscribed circle radius between adjacent conformal slit mapping iso-parameters. Lastly, the spiral path is derived by offsetting iso-parameters. The complexity and applicability of the proposed method are comprehensively analyzed across various boundary scenarios. Meanwhile, two cavities milling experiments are conducted to compare the new method with conventional spiral complete coverage path methods. The comparation indicate that the new path meets the requirement for complete coverage in cavity machining while reducing path length and machining time by 12.70% and 12.34%, respectively.Comment: This article has not been formally published yet and may undergo minor content change

Presence of CP4-EPSPS Component in Roundup Ready Soybean-Derived Food Products

With the widespread use of Roundup Ready soya (event 40-3-2) (RRS), the traceability of transgenic components, especially protein residues, in different soya-related foodstuffs has become an important issue. In this report, transgenic components in commercial soya (including RRS) protein concentrates were firstly detected by using polymerase chain reaction (PCR) and western blot. The results illustrated the different degradation patterns of the cp4-epsps gene and corresponding protein in RRS-derived protein concentrates. Furthermore, western blot was applied to investigate the single factor of food processing and the matrix on the disintegration of CP4-EPSPS protein in RRS powder and soya-derived foodstuffs, and trace the degradation patterns during the food production chain. Our results suggested that the exogenous full length of CP4-EPSPS protein in RRS powder was distinctively sensitive to various heat treatments, including heat, microwave and autoclave (especially), and only one degradation fragment (23.4 kD) of CP4-EPSPS protein was apparently observed when autoclaving was applied. By tracing the protein degradation during RRS-related products, including tofu, tou-kan, and bean curd sheets, however, four degradation fragments (42.9, 38.2, 32.2 and 23.4 kD) were displayed, suggesting that both boiling and bittern adding procedures might have extensive effects on CP4-EPSPS protein degradation. Our results thus confirmed that the distinctive residues of the CP4-EPSPS component could be traced in RRS-related foodstuffs