Robots have already become an indispensable part of our lives. However currently, most robots are relatively rigid machines which make unnatural movements. Inspired by living organisms, soft material robotics hold great promise for areas where robots need to contact and interact with humans, such as manufacturing and healthcare. Unlike rigid robots, soft robots can replicate natural motion – grasping and manipulation – to provide medical and other types of assistance, perform delicate tasks, or pick up soft objects
Soft robotics differ from traditional counterparts in some important ways: Soft robots have little or no hard internal structures. Instead they use a combination of muscularity and deformation to grasp things and move about. Rather than using motors, cables or gears, soft robots are often animated by pressurized air or liquids. In many cases soft robotics designs mimic natural, evolved biological forms hence also called bio-inspired robots. This, combined with their soft exteriors, can make soft robots more suitable for interaction with living things or even for use as human exoskeletons.
The emerging field of soft robotics aims to improve robot/human interactivity promising to bring robots into all aspects our daily lives, including wearable robotics, surgical robots, micromanipulation, search and rescue, and others. Soft robots can become aides for the disabled or the elderly if they can be trusted not to hurt the people they come into contact with. Miniature soft robots could even serve as surgical tools inside the body. Robots with greater flexibility could also help in military operations, where level terrain and unobstructed areas are rare, whether as a fully intact robot or as, say, a strap-on arm with a pneumatically controlled hand that could extend the reach, strength or capability of what a person could do.
Soft Robotics arms can come in handy when carrying these soldiers without causing injury. “We have lost medics throughout the years because they have the courage to go forward and rescue their comrades under fire. With the newer technology, with the robotic vehicles we are using even today to examine and to detonate IEDs [improvised explosive devices], those same vehicles can go forward and retrieve casualties,” Major General Steve Jones, commander of the Army Medical Department Center, said. Evacuating casualties was only one of the roles for robots in battlefield medicine that Jones discussed. Another option is delivering medical supplies to dangerous areas, supporting troops operating behind enemy lines.
Soft Robotics is the specific subfield of robotics dealing with constructing robots from highly compliant materials, similar to those found in living organisms. Soft robotics draws heavily from the way in which living organisms move and adapt to their surroundings. In contrast to robots built from rigid materials, soft robots allow for increased flexibility and adaptability for accomplishing tasks, as well as improved safety when working around humans.
Potential applications for these robots include patient rehabilitation, handling fragile objects, biomimetic systems and home care. They are crucial in the systems that deal with uncertain and dynamic task-environments, e.g. grasping and manipulation of unknown objects, locomotion in rough terrains such as ocean floor, and physical contacts with living cells and human bodies. These robots must move over rough terrain without getting stuck and need manipulators that can grab whatever strangely shaped Soft and deformable structures objects they encounter.
Many industries are searching for new ways to use robots, including developing machines that can work alongside humans and those that are more versatile than the single-task assembly line bots of years past. Company Soft Robotics has developed fingerlike grippers are made of flexible material, such as silicone, and powered by compressed air especially useful in warehouse and assembly line markets — particularly in the food industry, where robots aren’t typically trusted to handle delicate items like fresh produce.
“There is a great need in the health care system for lightweight, lower-cost wearable exoskeleton designs to support stroke patients, individuals diagnosed with multiple sclerosis and senior citizens who require mechanical mobility assistance,” said Larry Jasinski, CEO of ReWalk. Currently in the United States, there are an estimated 3 million stroke patients and 400,000 MS patients who are suffering from limited mobility due to lower limb disabilities.
Soft robots can become aides for the disabled or the elderly if they can be trusted not to hurt the people they come into contact with. Miniature soft robots could even serve as surgical tools inside the body.
“Despite its importance and considerable demands, the field of Soft Robotics faces a number of fundamental scientific challenges: the studies of unconventional materials are still in their exploration phase, and it has not been fully clarified what materials are available and useful for robotic applications; tools and methods for fabrication and assembly are not established; we do not have broadly agreed methods of modeling and simulation of soft continuum bodies; it is not fully understood how to achieve sensing, actuation and control in soft bodied robots; and we are still exploring what are the good ways to test, evaluate, and communicate the soft robotics technologies,” says IEEE Robotics and Automation Society.
Carnegie Mellon researchers are working to make a robot’s movements more human-like, incorporating technologies such as artificial muscles, touch sensors, stretchable films, flexible electronics and pressure-sensitive skins. DARPA supports Carnegie Mellon’s research—as well as research by iRobot and Otherlab—through its Maximum Mobility Manipulation, or M3, program. M3’s research into soft robotics aims to increase the mobility of robots while creating a framework for fast prototyping and production, including fabricating robotics with 3D printing.
Scientists are also studying how soft robots could lead to major breakthroughs in the development of self-repairing, growing and self-replicating robots, according to the IEEE Robotics and Automation Society. Borgatti explained how soft robots can react to their environments – a major factor for future government use. For example, soft robots can be designed to navigate difficult terrain like shifting sand and fall without being damaged – picking themselves up and correcting their course.
US Army exoskeleton to reduce Soldier injuries
According to the U.S. Army Public Health Center, Back pain is widespread in the Army and has a significant impact on operations. Lower back injuries result in more than 1 million lost, or limited, service days for soldiers each year, according to the U.S. Army Public Health Center. Roughly 460 soldiers are diagnosed with back overuse injuries every day, U.S. Army data shows
Working with Soldiers in the 101st Airborne Division, researchers at Vanderbilt designed SABER as a wearable device that is soft, lightweight and form fitting. This unmotorized device can be selectively engaged by the Soldier to assist lifting capabilities.
“[The Army] initially tried to create Iron Man,” Karl Zelik, a lead designer for SABER and associate professor of mechanical engineering at Vanderbilt University, said. “They had these full-body robotic systems that hoped to do everything but ultimately effectively did nothing because they [were] too bulky and heavy and complex and costly … This exosuit is about as far away from Iron Man as you can get.”
The exosuit design addresses needs identified by the Soldiers, such as aiding strenuous lifting tasks like ammunition resupply and reducing injury and fatigue, critical to readiness over sustained periods. Biomechanical evaluations revealed that the three-pound suit reduced stress on Soldiers’ backs by more than 100 pounds while lifting. Additionally, most Soldiers increased their endurance by over 60 percent while wearing SABER.
It is developed by the U.S. Army and Vanderbilt University, and slated to be deployed in the field in 2023.
The new suit, which weighs just three pounds, is a soft harness that soldiers strap around their shoulders and legs. Soldiers can press a button on the suit by their left shoulder, which activates the straps running along their back to help ease the burden when lifting heavy objects like artillery rounds, boxes or guns.
If military robot falls, it can get itself up
Scientists at the U.S. Army Research Laboratory and the Johns Hopkins University Applied Physics Laboratory have developed software to ensure that if a robot falls, it can get itself back up, meaning future military robots will be less reliant on their Soldier handlers.Based on feedback from Soldiers at an Army training course, ARL researcher Dr. Chad Kessens began to develop software to analyze whether any given robot could get itself “back on its feet” from any overturned orientation.
“One Soldier told me that he valued his robot so much, he got out of his vehicle to rescue the robot when he couldn’t get it turned back over,” Kessens said. “That is a story I never want to hear again.” Researchers from Navy PMS-408 (Expeditionary Missions) and its technical arm, the Indian Head Explosive Ordnance Disposal Technology Division, agree. They teamed up with JHU/APL and the prime contractor, Northrop Grumman Remotec, to develop the Advanced Explosive Ordnance Disposal Robotic System, or AEODRS, a new family of EOD robotic systems featuring a modular opens systems architecture.
A lightweight backpackable platform, which is increment one of the program, is expected to move into production later this year. One critical requirement of the program is that the robots must be capable of self-righting. “These robots exist to keep Soldiers out of harm’s way,” said Reed Young, Robotics and Autonomy Program Manager at JHU/APL. “Self-righting is a critical capability that will only further that purpose.”
To evaluate the AEODRS system’s ability to self-right, JHU/APL teamed up with ARL to leverage the software Kessens developed. The team was able to extend its ability to robots with a greater number of joints (or degrees of freedom) due to JHU/APL researcher Galen Mullins’ expertise in adaptive sampling techniques.
“The analysis I’ve been working on looks at all possible geometries and orientations that the robot could find itself in,” Kessens said. “The problem is that each additional joint adds a dimension to the search space—so it is important to look in the right places for stable states and transitions. Otherwise, the search could take too long.”
Kessens said Mullins’ work is what allowed the analysis to work efficiently for analyzing higher degree of freedom systems. While Kessens’ work determines what to look for and how, Mullins figures out where to look.” “This analysis was made possible by our newly developed range adversarial planning tool, or RAPT, a software framework for testing autonomous and robotic systems,” Mullins said. “We originally developed the software for underwater vehicles, but when Chad explained his approach to the self-righting problem, I immediately saw how these technologies could work together.”
He said the key to this software is an adaptive sampling algorithm that looks for transitions. “For this work, we were looking for states where the robot could transition from a stable configuration to an unstable one, thus causing the robot to tip over,” Mullins explained. “My techniques were able to effectively predict where those transitions might be so that we could search the space efficiently.”
Ultimately, the team was able to evaluate the AEODRS systems’ eight degrees of freedom and determined it can right itself on level ground no matter what initial state it finds itself in. The analysis also generates motion plans showing how the robot can reorient itself. The team’s findings can be found in “Evaluating Robot Self-Righting Capabilities using Adaptive Sampling,” published in IEEE’s Robotics and Automation Letters in August.
Beyond the evaluation of any one specific robot, Kessens sees the analysis framework as important to the military’s ability to compare robots from different vendors and select the best one for purchasing. “The Army and Navy want robots that can self-right, but we are still working to understand and evaluate what that means,” Kessens said. “Self-right under what conditions? We have developed a metric analysis for evaluating a robot’s ability to self-right on sloped planar ground, and we could even use it as a tool for improving robot design. Our next step is to determine what a robot is capable of on uneven terrain.”
Harvard University’s Wyss Institute
Army researchers have evaluated prototype devices developed for the Defense Advanced Research Projects Agency at Maryland’s Aberdeen Proving Ground. The prototype was developed by researchers from Harvard University’s Wyss Institute under DARPA Warrior Web program.
The lightweight Soft Exosuit is designed to overcome the challenges of traditional heavier exoskeleton systems, such as power-hungry battery packs and rigid components that can interfere with natural joint movement. The exosuit is made of soft, functional textiles interwoven into a piece of smart clothing that is pulled on like a pair of pants. It mimics the actions of leg muscles and tendons when a user walks and provides periodic assistance at the joints.
It is intended to be worn comfortably under clothing and could enable soldiers to walk longer distances, keep fatigue at bay, and minimize the risk of injury when carrying heavy loads. Alternative versions of the suit could eventually assist those with limited mobility as well
Instead of shielding the wearer, its purpose is to propel them forward and conserve their energy, explains Conor Walsh, lead researcher from Harvard’s Wyss Institute for Biologically Inspired Engineering. “We are intrigued by this challenge because we are so inspired by how our muscles and nervous systems work,” Walsh explains. Using a system of battery-powered sensors, motors, gears, cables and pulleys sandwiched between the fabric layers, the suit senses the wearer’s motion and responds to assist. So far, tests have shown energy savings of seven per cent, and in 2017 Walsh will share the final prototype “with more efficient actuators, sensors and cables,” he says
A series of webbing straps contain a microprocessor and a network of strain sensors— continuously monitoring various data signals, including the suit tension, the position of the wearer (e.g., walking, running, crouched), and more. Batteries and motors are mounted at the waist and cables transmit forces to the joints.
“The suit mimics the action of leg muscles and tendons so a Soldier’s muscles expend less energy,” said Dr. Ignacio Galiana, a robotics engineer working on the project. Galiana said the team looked to nature for inspiration in developing cables and pulleys that interact with small motors to provide carefully timed assistance without restricting movement.
Inspired by a deep understanding of the biomechanics of human walking, the Soft Exosuit technology is spawning the development of entirely new forms of functional textiles, flexible power systems, soft sensors, and control strategies that enable intuitive and seamless human-machine interaction.
lead Researchers at Harvard’s Wyss Institute and the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) at Harvard University have demonstrated that a tethered soft exosuit can reduce the metabolic cost of running on a treadmill by 5.4% compared to not wearing the exosuit. What it can do is running the 26.2 miles of a marathon while feeling like running 24.9 miles, or if you could improve your average running pace from 9:14 minutes/mile to 8:49 minutes/mile without weeks of training.
“Homo sapiens has evolved to become very good at distance running, but our results show that further improvements to this already extremely efficient system are possible,” says corresponding author Philippe Malcolm, Ph.D., former Postdoctoral Research Fellow at the Wyss Institute and SEAS.
The team hopes to continue this research to reduce the metabolic cost of running even more. “We only tested two actuation profiles in this study, so it will be interesting to see how much more the cost of running can be reduced with further optimization of the system,” says Malcolm. “Our goal is to develop a portable system with a high power-to-weight ratio so that the benefit of using the suit greatly offsets the cost of wearing it. We believe this technology could augment the performance of recreational athletes and/or help with recovery after injury,” adds Lee. The days of a battery-powered exosuit for high-performance runners are still beyond the horizon, as the actuator unit (including motors, electronics, and power supply) in this study was off-board, but the authors say technology is moving toward making an untethered assistive exosuit possible in the near future.
The Defense Advanced Research Projects Agency awarded a $2.9 million grant to Harvard University’s Wyss Institute for Biologically Inspired Engineering to continue its work on the Soft Exosuit, an exoskeleton made of soft, comfortable fabric. The suit includes sensors that are fitted on the knee, hip and ankle, to sense a person’s gait and gives them an extra push at just the right time. During the suit’s development, research has led to new kinds of textiles, flexible power systems and soft sensors, along with new methods of human-machine interaction, according to the lab.
Walsh team, at the Wyss Institute for Biologically Inspired Engineering, is also designing a fluid-powered glove for hand rehabilitation. The researchers designed silicon-based inflatable tubes to mimic the motion of fingers. By wrapping the hollow elastic in thin fibers, they could control how the material stretched and curved when air or water was pumped into the tubes. That way, the material itself assumes the correct shape when pressurized, eliminating the need for complex mechanisms and control systems to recapitulate hand movements. “One of the advantages of these types of soft robots,” says Walsh, “is that you can design complexity into the structure to simplify the control requirements.” He imagines that the robotic glove could supplement physical-therapy exercises, aiding patients who have difficulties with motor control.
Developers from Harvard’s School of Engineering and Applied Sciences and the Wyss Institute for Biologically Inspired Engineering have produced the first untethered soft robot — a quadruped that can not only stand up and walk away from its designers, but walk through snow, fire and even walk away after being run over by a car. “The soft robot is safe to interact with during operation, and its silicone body is innately resilient to a variety of adverse environmental conditions including snow, puddles of water, direct (albeit limited) exposure to flames, and the crushing force of being run over by an automobile.”, according to researchers.
Breeze Automation is building soft robots for the Navy and NASA
Developed as part of San Francisco R&D facility Otherlab, Breeze leverages the concept of highly adaptable soft robotics. The company’s robotic arms are air-filled fabric structures.
“The concept Otherlab has been developing for around seven years has been this idea of Fluidic Robots, hydraulic and Pneumatic Robots that are very cheap,” Cavalcanti told TechCrunch in a conversation ahead of today’s event. “Very robust to the environment and made with very lightweight materials. The original concept was, what is the simplest possible robot you can make, and what is the lightest robot you can make? What that idea turned into was these robots made of fabric and air.”
Breeze separates from much of the competition in the soft robotics space by applying these principles to the entire structure, instead of just a, say, gripper on the end of a more traditional robotic arm. “All of that breaks down the second you get out of those large factories, and the question of how do robots interact to the real world becomes a lot more pressing,” Cavalcanti says. “What we’re trying to do is take a lot more of the research around soft robotics and the advantages of being fully sealed systems that are moved with really compliant sources of actuation like air. It turns out that when you’re trying to interact with an environment that’s unpredictable or unstructured, and you’re going to bump into things and you’re going to not get it right because you don’t have full sensing of the state of the world. There’s a lot of advantages to having entire manipulators and arms be soft instead of just the end effector.”
Breeze showcased several works in progress, including a system developed for the Navy that uses an HTC Vive headset for remote operation. The company’s work with NASA, meanwhile, involves the creation of a robotic system that doesn’t require a central drive shaft, marking a departure from more traditional robotic systems.
“You’re now looking at robot joints that can handle significant loads, that could be entirely injection molded,” explains Cavalcanti. “You don’t need a metal shaft, you don’t need a set of bearings or whatever. You can just have a bunch of injection mold, or plastic pieces that’s put together and there’s your robot.”
US Navy’s requirement of soft robotics for underwater explosive ordnance disposal
US Navy had released a SBIR, to develop and demonstrate technologies to fabricate cost-effective rapidly deployable lightweight actuated inflatable single or dual arm manipulation systems for integration onto underwater unmanned platforms.
Nature provides many examples of animals that have developed superior strategies for manipulation of their surroundings through the use of soft, robust and fast mechanisms. These abilities have proven difficult to emulate with traditional engineering approaches, but new developments in inflatable technology using pressurized membranes made of compliant (elastomeric) materials create new opportunities for affordable manipulation systems for a range of naval underwater missions. Such manipulation systems would avoid costly motors by replacing them with pump driven fluid-filled fabric membranes.
These materials can be used in the fabrication of lightweight actuated inflatable manipulation systems which are resilient to impact, can be compactly stowed and are safe to operate near humans. The technical challenges include the design of integrated actuation and fabric, distributed actuation to mimic effective bio-inspired energy efficiency, and dexterity to perform an array of underwater tasks.
The manipulation system should be able to perform elementary tasks such as precise positioning of objects or tools, removal or emplacement of objects (lifting at least 25 pounds), and pull or twist manipulations (eg. unscrewing a cap from a pipe), which are common tasks performed in explosive ordnance disposal. Ideally, these arms would be capable of operating on land or underwater, to depths of 200 feet.
DARPA’s Maximum Mobility and Manipulation (M3)
Robots hold great promise for amplifying human effectiveness in Defense operations. Compared to human beings and animals, however, the mobility and manipulation capability of present day robots is poor. In addition, design and manufacturing of current robotic systems are time consuming, and fabrication costs remain high. If these limitations were overcome, robots could assist in the execution of military operations far more effectively across a far greater range of missions.
The Maximum Mobility and Manipulation (M3) program is striving to create and demonstrate significant scientific and engineering advances in robotics that will:
- Create a significantly improved scientific framework for the rapid design and fabrication of robot systems and greatly enhance robot mobility and manipulation in natural environments.
- Significantly improve robot capabilities through fundamentally new approaches to the engineering of better design tools, fabrication methods, and control algorithms. The M3 program covers scientific advancement across four tracks: design tools, fabrication methodologies, control methods, and technology demonstration prototypes.
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