ASAM CPX is an extension of the ISO OTX standard (ISO 13209), which defines functions to describe test procedures for the calibration of ECUs, i.e. to determine and validate the parameters of ECU software. This task is traditionally carried out by technical experts, who use their expert-knowledge in test runs on simulation models, test benches or with prototype vehicles. This expert-knowledge is business-critical IP of each company. However, without a standard, the knowledge is either not documented at all, or it is documented in formats chosen by the experts, e.g. verbal descriptions, Excel sheets or in a scripting language. Knowledge transfer among experts within the company, test automation, data exchange between tools and reproducibility of tests are inhibited and depend on the personal capabilities of a few experts.
ASAM CPX shall solve this problem by providing a formal description method, based upon ISO OTX, which provides the necessary functions to specify ECU calibration tests. ASAM CPX extends ISO OTX with a programmatic access API to calibration and measurement data on the ECU, access to meta information about this data (from A2L files), functions for controlling the execution of measurement tests and simulation models, and specific mathematical functions. Further extensions of OTX even allow to use flow charts and state machines to describe the calibration process.
With the help of ASAM CPX, a company can now create comprehensive libraries of test sequences for all typical ECU calibration tasks, transfer this knowledge easily to new staff members, share the knowledge with their customers or suppliers, and increase the degree of automation step-by-step as better automation tools become available. In conjunction with ISO OTX part 1 to 3 and ASAM OTX part 4 and 5, a comprehensive language and exchange format is available for the automotive industry, which allows to specify the ECU calibration processes in detail and to freely exchange this knowledge.