Discrete Event Control Previous:

Discrete Event Control

Introduction

Reverse engineering is essentially the problem of constructing a model from sensed information. To do so within the tolerances needed in most manufacturing applications requires sophisticated sensing such as with a coordinate measuring machine (CMM). A CMM uses a robot arm to move a relatively delicate sensor in contact with the object to be sensed. To navigate this sensor efficiently and without collision requires some information about the object to be sensed. In an inspection situation, this information is typically the CAD model from which the part was manufactured. In a reverse engineering situation, the CAD model is not available, and this information must come from some other form of non-contact sensing such as intensity or range sensors. This information will typically be less accurate than the original CAD model unless considerable time and expense is spent on non-contact sensing. A robust control system can be used to make up for this.

Unifying the control of hybrid systems can pose a difficult problem. We feel that discrete event dynamic systems (DEDS) are very appropriate for the control of such systems. We have implemented such a strategy and introduce the dynamic recursive context for finite state machines (DRFSM) as a new DEDS tool for utilizing the recursive nature of the mechanical parts under consideration.