In this paper, properties of mixed discrete and continuous systems are clarified for computer scientists, to help them to have a good grasp of corresponding control theory concepts. This authoritatively well-written paper is based on the author’s doctoral thesis, and benefits from the results of nine hybrid system studies.

A formal specification and an intuitive description of a simple example system to control the height of the chassis of a car are presented. The intuitive description is also expressed as a HySChart, a variant of Statechart. Two variables are monitored: the height of the chassis, and whether the car is on a curve. When the car is on a curve, no control is performed. If the car is not on a curve, and if the height is within acceptable boundary values, no control is performed. If the height is below a threshold, a compressor actuator becomes active to increase the height; if the height is above a threshold, another actuator, an escape valve, is activated to lower the chassis.

Robustness, optimization, stability, and attraction, as well as universal and existential properties, are explained in detail. Afterward, classification of properties, some proof concepts, the contribution of the study, and related work are presented.

The empirical aspect of dynamic system studies, namely, simulation, is not even mentioned. A bend (or a curve) is important in the example; however, no characteristic of the curvature of the road is mentioned. It would be interesting to know how adding just speed control would complicate the theoretical study.