Our Eddy Current Braking Technology

The technology inside many of our devices is our patented eddy current magnetic braking, which is explained in the video below.

What are eddy currents?

Eddy currents happen when you move non-magnetic metals through a magnetic field.

What is eddy current braking?

Eddy current braking uses a phenomenon called electromagnetic induction, where motion between a magnet and non-magnetic metal causes a force opposing the motion between the two objects. As a result, kinetic energy (which is movement) is converted to thermal energy (which is heat).This braking happens entirely without contact. When the conductive material in the magnetic field is still, no reaction occurs. When the conductor moves while in the magnetic field, a magnetic field and eddy currents are generated within the conductor that opposes the direction of the current of the magnetic field of the permanent magnet to create the braking effect. This is called an “eddy current” because the current doesn't travel in a straight line. The induced current swirls within the conductor, like eddy currents in a river.

How is eddy current braking used in our devices?

In our devices, a retraction spring winds the webbing into the device. When force pulls the webbing out of the device, aluminum rotor arms are sent spinning into a magnetic field. This creates the eddy currents which control the braking force and the speed at which the spinning occurs, which then controls the speed at which the webbing comes out. Our eddy current braking system is self-regulating. This means that the braking resistance automatically adjusts itself to provide consistent braking across a wide range of participant weights – a huge advantage over other auto belays used for climbing or fall protection.

What are the benefits of eddy current braking in these devices?

There are many benefits of incorporating eddy current braking into our devices. Our devices are:

  • Low maintenance – Because the braking is magnetic, there are not any contacting parts in the braking system and there are no components, such as brake pads, to wear out or fail; as a result, there is less maintenance and a low ownership cost for our devices
  • Self-regulating – Because the braking system is self regulating, our devices can accommodate a wide range of weights, so children and adults alike have a consistent experience
  • Smooth and comfortable – Whether jumping, descending or approaching a platform, the experience is smooth and comfortable


The advanced technology inside many of our devices is is covered by
U.S. Pat No’s. 8,490,751; 8,851,235; 9,016,435 and D654,412 and corresponding patents in other countries worldwide.