RHex: The ‘Parkour Robot’ Can Flip, Jump, and Do Pull-Ups
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RHex: The ‘Parkour Robot’ Can Flip, Jump, and Do Pull-Ups |
The original design for the robot was developed around 10 years ago, but this lighter version — X-RHex Lite (RXL) — was developed by UPenn professor Daniel Koditschek and his graduate student Aaron Johnson. They are teaching it freerunning, or Parkour, with the intent that it will one day be used for applications like searching the jagged rubble of a collapsed building for survivors, or traversing the shifting sands and rocky obstacles of the desert while taking environmental readings.
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X-RHex Lite (RXL) was developed by UPenn professor Daniel Koditschek and his graduate student Aaron Johnson |
"What we want is a robot that can go anywhere, even over terrain that might be broken and uneven," Johnson says. "These latest jumps greatly expand the range of what this machine is capable of, as it can now jump onto or across obstacles that are bigger than it is."
XRL differs from its earlier relatives by using lighter materials and simpler fabrication methods. A complete shell of carbon fiber panels surrounds the XRL frame, and it has only a single battery compartment. The XRL is 51 cm (20 in) long, 40.5 cm (16 in) wide, and the body alone is 10 cm (four inches) in thickness. The diameter of the six flexible rotating legs is 17.5 cm (6.9 in), giving the XRL ground clearance of 11 cm (4.3 in) regardless of which end is up at the moment. It's weight including battery pack is 6.7 kg (14.7 lb).
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The XRL is 51 cm (20 in) long, 40.5 cm (16 in) wide, and the body alone is 10 cm (four inches) in thickness,weighs 6.7 kg (14.7 lb) including battery pack |
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For motive power, the XRL depends on two 50 watt brushless pancake electric motors with peak power of about 380 watts, or about half a horsepower |
The XRL legs are equipped with force and power sensors, which allow the work of maneuvering to be analyzed in detail. Among other benefits, the research team found that the response of the legs can be used to give an indication of on what sort of surface the XRL is walking. For example, the XRL responds to vinyl and asphalt surfaces in very much the same manner, but responds very differently to pebbles or grass surfaces (which are in turn similar to each other).
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XEL leg response to being driven over different landscape textures |