A US company has launched a fund-raising campaign to build a prototype "slingatron" that could be used to propel a 100 g object to a speed of one kilometre per second. HyperV Technologies, based in Virginia in the US, is now attempting to raise $250,000 via the crowd-funding website Kickstarter to build the device, which it says will pave the way for a full scaled-up version that can launch much heavier cargo into space.
A slingatron is based upon an old-fashioned weapon known as a "sling" – it involves a heavy mass on the end of a rope, which a person whirls around their head with increasing frequency before letting go, sending the object flying. However, with the slingatron the rope is replaced by a spiral track spinning at a constant frequency. When an object is released from the middle, it follows the track round with an increasing radius, getting faster and faster as it does so. The larger the final radius – and the greater the spin frequency – the faster the object travels when it leaves.
The idea for this sort of mechanical propulsion is not new. In 2006 it was revealed that the US Defense Advanced Research Projects Agency spent around $5m a year to explore whether a slingatron could accelerate masses to extremely high speeds without using rockets, before claiming that the approach was unpromising.To read more, click here.