The Defense Advanced Research Projects Agency (DARPA) recently embarked on a new initiative to develop robotic autonomous manipulators that mimic human arms, wrists, hands and fingers. The goal of the program is to surpass the performance of tasks currently performed by remote manipulation systems that are controlled directly by a human operator.
“In the areas of manipulation, there is a great need to advance the state of the art in robots’ abilities to perceive their environment, understand the objects that they’re trying to manipulate, be able to pick those objects up and manipulate them,” says Dr. Robert Mandelbaum, program manager for the Information Processing Technique Office at DARPA, the group that focuses on robotics and autonomous systems.
According to Mandelbaum, current technology requires “burdensome human operation, and high-precision arms and hands, yet a two-year-old child manipulates better.” The ARM program will enable military applications that should revolutionize the battlefield by making robots just as dexterous, resilient and flexible as humans.
Mandelbaum envisions mobile manipulators with a high degree of autonomy, requiring only high-level supervision by an operator, thus simplifying human control and improving the execution of military tasks. Potential applications include search and rescue; weapons support; checkpoint and access control; explosive ordnance disposal; and casualty care, including battlefield extraction and treatment.
To develop autonomous capabilities for mobile manipulators that “improve task performance and remove direct human control,” Mandelbaum and his colleagues have embarked on a hardware track and a software track, each with three development phases.
One of the key goals of the program is to lower manufacturing costs by “at least one order of magnitude less than multi-fingered hands on the market today. Among other methods, the low cost should be achieved by dispensing with high-precision engineered parts, and recovering precision by way of perception-based feedback control; utilizing techniques such as ‘minimalist’ design that reduces complexity and part count; and use of economies of scale or production volume.”
To help address that challenge, DARPA has partnered with two leading-edge robotic companies: Barrett Technology Inc. and RE2 Inc. They will provide the hardware, software, integration services and manipulation expertise for the multi-year research program.
Barrett Technology will provide the ARM effort's manipulation hardware, including the Barrett WAM Arm and BarrettHand. RE2 will provide manipulator integration services, applying its manipulation expertise to integrate the Barrett technology with various sensing technologies and a mobile platform.
For the ARM program, DARPA will select a set of teams that will be given identical government-furnished hardware and will be tasked to create algorithms to maximize the manipulation capability. Engineers will develop the best autonomous software for performing complex manipulation tasks.
“DARPA’s overall technical objective for the ARM program is to enable high-level control of ‘hands on’ contact tasks, with the mobile manipulation system following a high-level script and performing low-level subtasks on its own,” says William Townsend, CEO of Barrett Technology. “Autonomously controlled, high-degree-of-freedom robotic arms, wrists and hands to grasp and manipulate objects [will] perform tasks, including mobile navigation, as necessary.”
The ARM program will consist of a series of real-world tasks that become progressively more difficult. It will involve grasping a wide variety of different objects, some known and some partially known.
Phase 1 of the grasping test will require the manipulator to pick up objects such as flashlights, pistols, knives, screwdrivers, telephone handsets, mines, radio handsets, circuit boards, grenades, rocks, pipes, fins and branches.
Phase 1 of the manipulation test will include performing tasks such as writing with a pen; sorting objects by pushing them on a tabletop; stapling together papers already placed in a stapler; drilling a hole using a power tool; throwing a ball; sliding a sheet of paper along a tabletop; inserting a key into a lock and turning the key to unlock it; and turning wheels, knobs and levers on an instrument panel.
Phase 2 of the grasping challenge will require the manipulator to pick up a pair of pliers; a key and lock set; a cell phone that slides open; a cell phone that flips open; a meal ready to eat; a boot; a utility pouch with a belt loop; a shirt; a duffle bag; a mortar round; a shovel; a brick; and a log.
Phase 2 of the manipulation challenge will involve performing actions such as holding an inert grenade with one hand and pulling the pin with the other hand; holding a jar with one hand and unscrewing the lid with the other hand; assembling an object from a kit of parts; inserting a battery into an electronic device; pouring a glass of water; fitting a connector into a mating receptacle; putting the cap on a pen; applying duct tape; removing duct tape; zipping open a duffle bag; cutting a wire; tying a knot in rope; and removing a card from a wallet.
Phase 3 of the grasping test will require the manipulator to hold bolt cutters, a mortar, a rifle, a backpack, a flexible toolkit, a full trash bag, rope, an ammunition box, rubble, a partially buried mine and a cinder block.
Phase 3 of the manipulation test will involve performing tasks such as loading a mortar round into a mortar tube; opening a gym bag; and picking up and removing rubble.