List of birds by flight speed
This is a list of the fastest flying birds in the world. A bird's velocity is necessarily variable; a hunting bird will reach much greater speeds while diving to catch prey than when gliding. The bird with the greatest airspeed velocity is the Peregrine falcon, able to exceed 321.8 km/h (200 mph) in its hunting dives. The greatest self-powered horizontal speed is achieved by Homing Racing Pigeons. They can fly 1100 km (700 miles) in a single day, and they have been recorded flying at 177 km/h (110 miles per hour), making them the birds with the fastest speed ever recorded on a self-powered flight, and the fastest endurance flight.
MABEL (robot)
MABEL (robot) is a robot engineered in 2009 by researchers at the University of Michigan, which is well known for being the world's fastest bipedal (two-legged) robot with knees. MABEL is able to reach speeds of up to 3.6 m/s (6.8 mph). The name MABEL is an acronym for Michigan Anthropomorphic Biped With Electronic Legs. The creators include J.W. Grizzle, Jonathan Hurst, Hae-Won Park, Koushil Sreenath, and Alireza Ramezani. MABEL weighs 143 pounds (65 kilograms) with most of its weight being in the top torso area. The legs contain large springs and are jointed to form knees. The robot is attached to a safety boom for lateral stability.
In order to make MABEL functional for extended periods of time, the researchers focused on ways to optimize powertrain efficiency. Unlike the RABBIT, MABEL was designed to have all four motors in the midsection instead of the legs. This makes the legs lighter and more agile. Secondly, most of MABEL’s power is stored in large springs that act to reduce shock and store energy. MABEL uses a differential so that the spring can be grounded by the torso of the robot instead of directly connected in series with a motor. This allows the compression in the springs to better apply force that pushes up the center of mass. Another innovative aspect of the springs is that they are referred to as “unilateral” because they don’t extend past the rest length, causing undirected force.