Like a teenager going off to college, DARPA's Atlas robot has cut the tether and is walking on its own without a safety line. The centerpiece of this year's DARPA Robotics Challenge (DRC), the upgraded Atlas robot was unveiled to the competing teams in Waltham, Massachusetts last week during a technical shakeout.

Developed for DARPA by Boston Dynamics, the 6 ft 2 in (1.88 m), 345 lb (156.5 kg) bipedal, humanoid Atlas robot is designed for exploring ways to use robots in disaster situations – especially where navigating debris and using tools or found objects is necessary. According to DARPA, the upgrades to the Atlas increase its efficiency, dexterity, and resilience, with 75 percent of it replaced with new components and only the lower legs and feet remaining from the original design.

The new Atlas uses lighter materials than the previous version. This allowed the engineers to add an onboard 3.7 kWh lithium-ion battery pack and a new variable-pressure pump system. This is not only quieter than the old one, but DARPA says that it provides one hour of "mixed mission" operation with different power requirements for different tasks.

"The introduction of a battery and variable-pressure pump into Atlas poses a strategic challenge for teams," says Gill Pratt, program manager for the DRC. "The operator will be able to run the robot on a mid-pressure setting for most operations to save power, and then apply bursts of maximum pressure when additional force is needed. The teams are going to have to game out the right balance of force and battery life to complete the course."

The Atlas robot will be capable of operating without a tether (Image: DARPA)

The arms and shoulders have been repositioned to provide more space inside the torso and to allow the robot to use its hands in front of its body, so the operator can see what's happening through the robot's eyes. In addition, the lower arms are now electrically powered, and the Atlas can turn its wrist, so it can work a doorknob.

Other improvements are the actuators in the the hip, knee, and back, which are larger for greater strength, the three onboard perception computers for perception and task planning, and in the head there's a wireless router for remote control and to serve as a kill switch so the operator can shut down the robot remotely.

The upgrades reflect the raising of the bar for this year's finals of the DARPA Robotics Challenge that require the competitors to drastically improve their robots and software. One class of contestants will be issued with Atlas robots, which they must design software and control systems for. Unlike the previous rounds, robots competing in the Finals cannot have safety tethers, wire control, or external power.

In addition, the robots must run the course without physical help, so the robot must be able to stand up if it falls and free itself if it gets stuck. DARPA also says that at one point on the course it will deliberately degrade the wireless communications for greater realism and to test the machine's ability to act autonomously.

About 20 teams are expected to compete on June 5 and 6 at Fairplex in Pomona, California. DARPA says that the Challenge now offers US $3.5 million in prizes: US$2 million grand prize, US$1 million runner-up, and US$500,000 third-place.

The seven DRC teams using Atlas will receive their upgraded robots by the end of this month. These will include a battery emulator, which will help the teams to simulate how a real battery will perform in the competition and how to switch between constant and metered voltage.

DARPA is still accepting new competitors until February 2 and will announce the qualifiers in March.

The video below outlines the Atlas upgrades.

Source: DARPA