The last time we wrote something about a multi-legged robot—the Plustech Walking Forest Machine—the post went viral. Maybe because the thing looked like it was straight out of the movie Avatar.
Well, maybe the world is getting a little more like James Cameron’s future every day … because some interesting news just surfaced about the use of hydraulics in Mantis, the largest operational all-terrain hexapod robot. Mantis is making an appearance at a forestry expo in Sweden this month. The 9-ft robot, which can be driven remotely or piloted from the machine’s cockpit, took four years to develop and features Bosch Rexroth fluid power components.
The company says that 18 Rexroth 4WREE6 valves provide the integral function of controlling the hydraulic cylinders that operate Mantis’ six legs. Each leg features three independent closed-loop axes—one at the knee and two at the hip—with feedback provided by sensors installed on the outside of the leg.
Mantis is the brainchild of chief designer Matt Denton, managing director of Micromagic Systems, who created the computer controls that give the machine its high functionality. These include the ability to move omni-directionally (forwards/backwards, crab left/right, turn left/right), climb over uneven ground and raise and lower on command.
“I’d been making smaller hexapod robots for a number of years for use in the film and TV industries as well as for private collectors,” Denton said. “I felt that if I could scale up the machine to the point where it could carry a person that, as well as demonstrating what is possible with current technologies and British engineering, there could be further applications both in the film industry and other sectors, such as unmanned subsea exploration, and work in environments that are sensitive to terrain damage.”
“I was aware of Bosch Rexroth valves from their use in special effects on films I’d worked on in the past. … [sector manager Nigel Hart] provided assistance and advice on the hydraulic design of circuits, safety considerations, reducing the reservoir size and cooling. What impressed me most about the Bosch Rexroth valves, and proved essential to the functionality of the machine, was the smooth and accurate control they provide.”
Mantis also features a Rexroth A10VO63DFR pump, typically used in booms and cranes that supplies the robot’s hydraulic power. Fitted with load sensing, the pump ensures only the right flow and pressure is delivered, reducing overall power consumption.
“Mantis is a fantastic demonstration of what can be achieved with today’s technology. It is also indicative of the significant changes that have happened throughout the industry over the past 10-15 years,” said Nigel Hart, sector manager for Marine and Offshore at Bosch Rexroth U.K. “Now even the most simple of components come with intelligence that allows it to perform a variety of functions and adapt to a number of applications.”