Automated Test Approach Based on All Paths Covered Optimal Algorithm and Sequence Priority Selected Algorithm

A timely and complete test is an important factor to assure the functionality and safety of a railway signal system before it is put into service. With the development of rail transportation in China, the traditional semiautomatic test methods cannot satisfy the timely and complete test requirements any longer. This paper proposes an automated model-based test method. First, colored Petri nets are used as a formal language to describe the system specification. Second, the all paths covered optimal algorithm and the sequence priority selected algorithm are proposed to generate the test cases and sequences automatically. Third, taking a typical radio block center (RBC) handover scenario as an example, the generated test cases and sequences are applied into the RBC functionality test platform. The testing result validated the feasibility and efficiency of the proposed automated test method. Compared with the random-walk-based test sequence generation algorithm, the repeatability rate of the generated test sequences is reduced by 46%. The test sequences can cover all the generated test cases, and the cases can cover all the related criteria in the function requirements specification of the Chinese Train Control System Level 3.