Effects of electromagnetic interference on controller-computer upsets and system stability

Electromagnetic interference (EMI) causes controller upsets manifested as e rrors in control-law computation on a controller computer, or as disturbanc es in data transmission between sensors/actuators and the controller comput er, which may be critical to system stability. In this paper, we compute th e probability of these EMI-induced upsets in terms of the parameters govern ing EMI behaviors and the conditional probabilities of upsets in the presen ce of EMI, which is useful for the design and verification of the integrity of reliable controllers. The results are used to modify a system dynamic e quation to examine asymptotical stability with probability one for the rand om sequences of the system states evolving according to the resultant dynam ic equation, which are validated via a simple EMI experiment in a reverbera tion chamber.