March 8, 2007 The logging of forests is a very expensive affair, and when there’s a lot of money involved, you can always count on some very special machinery. Two perfect illustrations of this are Plustech/TimberJack/John Deere’s walking tractor prototype (videos here, here and here) and Triton Logging's Sawfish Underwater Harvester. The value of underwater forests in Canada was deemed so large that Triton has developed the Sawfish, a 3-tonne, 3.5-metre-long, yellow submersible with high-resolution cameras so an operator can direct it from the surface. The Sawfish then grasps the base of the tree with its powerful pincers, attaches an inflatable flotation bag to the tree, fills the bag with compressed air and then it cuts the tree with its 1.5-metre chainsaw and the flotation bag carries it to the surface – it can actually handle larger trees than any land-based mechanical harvester due to water buoyancy. As the world’s only deep-water logging machine, it’s a mash-up of remote control, timber-harvesting and submarine technology that can cut down a dozen trees in an hour, at depths of up to 300 metres. The machines are now available to other logging companies at a price around US$750,000 and with no new roads to build and no fires to control, logging underwater suddenly makes economic sense.
Read the full article: Innovative machines invade the forest – the Sawfish Underwater Harvester