1 Introduction

Trigonometric functions are commonly used in real-time control applications, particularly within the inner loops of control algorithms, where speed and accuracy is essential. The performance of trigonometric functions is a key careabout for designers of these systems as it can have a significant impact on the overall performance of the system. Until recently, trignometric functions based on lookup tables were considered faster than the polynomial-based methods; however, with the inclusion of floating-point units (FPUs) and faster CPU clock speeds, polynomial-based approximations are gaining favor.