Accessibility, as the most important qualitative index of maintainability, is the first element of maintainability design analysis. Virtual maintenance technology provides a technical approach for automatic quantitative evaluation of accessibility because of its advantages such as simulating physical environment and effectively obtaining spatial data. However, the development of accessibility analysis and evaluation technology is not mature, the current accessibility analysis and evaluation methods are still qualitative, relying on the subjective observation and experience of the evaluators, there are some problems, such as the evaluation work is time-consuming and laborious, and the evaluation results lack objective data support. This paper proposes a method for quantitative analysis of accessibility based on path planning. In this paper, arm comfort is used as an index to evaluate the accessibility path, and the accessibility evaluation results are obtained. Firstly, comfort is introduced as a constraint to optimize FABRIK algorithm to automatically obtain the final grasp posture and comfort score of the virtual arm with the best comfort, and the quantitative evaluation results are obtained.