Control performance improvements due to fluctuations in dynamics of stochastic control systems

Human motor control mechanisms are distinguished by two remarkable properties: time delays and random fluctuations. In this work, we focus on these two properties and investigate the effects of fluctuations on the stability and behavior of a stochastic linear time-delay system. The control performance improvements due to fluctuation are presented using numerical simulations as well as its theoretical analyses. In conventional controller design, a random component such as fluctuation is targeted for removal from the system as a factor causing performance reduction. However, the results presented in this paper suggest that an appropriate fluctuation component in control systems can help to achieve better control performances.