With large-scale wearable props, power and weight are directly linked. You can calculate the wattage required to lift a load, but it all boils down to this: the heavier it is, the harder it is to move. Imagine holding your arm out straight, and now imagine doing it while holding a weight. That extra effort? That’s what I’m trying to reduce in the wing design.

I also wanted the wings to look and move more anatomically correct. A lot of wing props hinge at a single point near the top of the shoulder. That works fine for static photos, but it creates problems when the wings are folded down. They tend to stick out weirdly or bump into things, which isn’t great when you're navigating a crowded con floor. Worse, they often hinge from the wrong point, which makes them move in ways real wings never would. That leads to feathers bunching oddly, weird geometry, and general jankiness.

The power needed to lift the wings is essentially just the energy required to overcome gravity. In broad terms, three things control that: the shape of the system, the weight (or inertia), and how fast you want the wings to move. Most wing builds solve this by using slow but powerful linear actuators. That trades speed for torque, which is fine, but I wanted a more elegant solution.

For my version, I used a **constant force spring**. These are coiled springs that apply the same force across their entire stroke (unlike normal springs, which get harder to pull the further you stretch them). This lets the wings “float” under tension, dramatically reducing the power needed to move them.

The best way I can describe it is like tying a balloon to your arm that offsets its weight. You’re still moving it, but the spring is helping enough that it feels easy. The motor still has to overcome inertia, but it no longer has to fight gravity the whole time. That means nearly all the available power goes into moving the wings, not just holding them up.

For the wing geometry, I didn’t overthink it. I wanted them to look like bird wings, so I looked at bird wings. Nature’s had millions of years to optimize joint placement—I’m not too proud to steal those insights and move on.

To keep the build lightweight, I used aluminum pipe for the structure. It’s strong, cheap, and easy to cut to size. I’ve used it on a bunch of other projects and it’s always a go-to when strength-to-weight matters.