Remember that submission about the math for SEP? Well, here are some of the numbers I need for it! (hoary) This drawing includes the dimensions from the opening of the cabling sheath to the center of the controlling servo's horn. Using this, and the previous page of math, I can write a controller to completely linearize the movements.

The animation rack for SEP does not use a pulley system to draw the cables in at a constant rate, instead it just uses a lever arm. This means that the relation of horn angle to cable drawn in is very non-linear. However, the benefit is that the ears will be able to "lock over center", so certain poses will require no power to maintain. The batteries will last longer and the ears wont just fall limp when power is turned off.

And yes, I do obsessively CAD everything I work on. I had this design long before I started posting here, it is just good practice.

What is Secret Ear Project? It my personal project, aimed at creating animatronic ears, compact enough to wear the entire device on a hat. Watch my gallery for updates as I move along.