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arXiv · 2112.01204

Formal verification of a controller implementation in fixed-point arithmetic

Lars Flessing·Grigory Devadze·Stefan Streif
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Abstract

For the implementations of controllers on digital processors, certain limitations, e.g. in the instruction set and register length, need to be taken into account, especially for safety-critical applications. This work aims to provide a computer-certified inductive definition for the control functions that are implemented on such processors accompanied with the fixed-point data type in a proof assistant. Using these inductive definitions we formally ensure correct realization of the controllers on a digital processor. Our results guarantee overflow-free computations of the implemented control algorithm. The method presented in this paper currently supports functions that are defined as polynomials within an arbitrary fixed-point structure. We demonstrate the verification process in the case study on an example with different scenarios of fixed-point type implementations.

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Lars Flessing, Grigory Devadze, Stefan Streif. 2021-12-02. Formal verification of a controller implementation in fixed-point arithmetic. https://arxiv.org/abs/2112.01204

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