Springfree Trampoline

Springfree Trampoline is a company that manufactures recreational trampoline products and accessories. The design was created by Keith Vivian Alexander, a professor in the Mechanical Engineering Department at the University of Canterbury in Christchurch, New Zealand.

History
After analysing trampoline data in 1992, Alexander noted three impact zones affecting jumper safety in the George Nissen trampoline design. These were:
 * 1) The springs – on the jumping surface.
 * 2) The steel frame – on the jumping surface/ jumpers may fall and injure themselves.
 * 3) The ground or obstructions on the ground – jumpers would hit as a result of falling off.

Alexander's goal was to increase the trampoline's safety by re-engineering the spring technology. In 1999, Alexander released his first prototype utilising glass-reinforced plastic rods, and the first commercial versions began selling in late 2004. In 2009, Springfree Trampoline won an Australian Design Award.

Design
The Springfree trampoline's design includes the use of glass-reinforced plastic rods articulating below the jumping surface, as opposed to the radiating steel spring coils of a Nissen trampoline. The jumping surface is lowered around 450mm below the jumping surface of a traditional trampoline, and the base's rigidity is derived from a tubular steel assembly with angled supports.