Model-based Physical System Deployment on Embedded Targets with Contract-based Design

摘要

Designing model-based physical systems has growing demand in consequence of increasing system complexity. In particular, observers/estimators are extensively used for the applications requiring state or disturbance estimation. Designing and deploying such numerically intensive physical systems onto embedded targets is a challenging task that requires co-design among various stakeholders from different technical backgrounds. The most important challenge is to obtain a numeric behavior of the estimator from an embedded target, that is able to represent the physical system states/disturbance with an acceptable error margin. Moreover, this error margin needs to be decided by the stakeholders, which makes the overall embedded deployment a co-design problem. The main contribution of this paper is to investigate the cause of the estimation error of an estimator that is deployed to embedded targets. This error is studied in the form of precision loss in addition to the error originating in the decreasing estimator measurement frequency for the embedded targets. We propose Assume-Guarantee (A/G) contracts to reconcile the viewpoints of the stakeholders, who reside at different abstraction levels. The feasibility of the proposed physical system deployment method is presented by utilizing a model-based virtual sensor estimator deployment for embedded targets as a case study.