Tool Path Planning with Confined Scallop Height Error Using Optimal Connected Fermat Spirals

Abstract

In CNC machining, the tool path planning of the cutter plays an important role. In this paper, we generate a space-filling and continuous tool path for free-form surface represented by the triangular mesh with a confined scallop height. The tool path is constructed from connected Fermat spirals (CFS) but with fewer inflection points. Comparing with the newly developed CFS method, only about half of the number of inflection points are involved. Moreover, the kinematic constraints are simultaneously taken into account to increase the feedrates in machining. Finally, we use a micro-line trajectory technique to smooth the tool path. Experimental results and physical cutting tests are provided to illustrate and clarify our method.

Keywords

Tool path planning / Connected Fermat spirals / Scallop height / Kinematic constraints

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Funding

Natural Science Foundation of Beijing Municipality(Z190004); Key Technologies Research and Development Program(2020YFA0713703); National Natural Science Foundation of China(11688101); Fundamental Research Funds for Central Universities of the Central South University