Sine-Cosine Approximations

A microcontroller-based design used sine and cosine functions to control circular positioning. We needed

We needed to compute sine and cosine functions for a control application. We decided to write a white paper on how we did it.

A microprocessor-based design needed to create a circular motion by using the cosine and sine functions to drive X and Y positioners. The exact equations for these functions are infinitely long polynomial, so approximation were needed. We studied three, each with tradeoffs between accuracy and calculation speed.

Our real-time application needed fairly quick calculations but not high accuracy, so we chose the simplest of the three.

Here’s the link: White Paper – Simple Sine Approximations.