By Taylor Kubota, Stanford News Service

Imagine rescuers searching for people in the rubble of a collapsed building. Instead of digging through the debris by hand or having dogs sniff for signs of life, they bring out a small, air-tight cylinder. They place the device at the entrance of the debris and flip a switch. From one end of the cylinder, a tendril extends into the mass of stones and dirt, like a fast-climbing vine. A camera at the tip of the tendril gives rescuers a view of the otherwise unreachable places beneath the rubble.

This is just one possible application of a new type of robot created by mechanical engineers at Stanford University, detailed in a June 19 Science Robotics paper. Inspired by natural organisms that cover distance by growing — such as vines, fungi and nerve cells — the researchers have made a proof of concept of their soft, growing robot and have run it through some challenging tests.

“Essentially, we’re trying to understand the fundamentals of this new approach to getting mobility or movement out of a mechanism,” explained Allison Okamura, professor of mechanical engineering and senior author of the paper. “It’s very, very different from the way that animals or people get around the world.”

To investigate what their robot can do, the group created prototypes that move through various obstacles, travel toward a designated goal, and grow into a free-standing structure. This robot could serve a wide range of purposes, particularly in the realms of search and rescue and medical devices, the researchers said.

A growing robot

The basic idea behind this robot is straightforward. It’s a tube of soft material folded inside itself, like an inside-out sock, that grows in one direction when the material at the front of the tube everts, as the tube becomes right-side-out. In the prototypes, the material was a thin, cheap plastic and the robot body everted when the scientists pumped pressurized air into the stationary end. In other versions, fluid could replace the pressurized air.

What makes this robot design extremely useful is that the design results in movement of the tip without movement of the body.

“The body lengthens as the material extends from the end but the rest of the body doesn’t move,” explained Elliot Hawkes, a visiting assistant professor from the University of California, Santa Barbara and lead author of the paper. “The body can be stuck to the environment or jammed between rocks, but that doesn’t stop the robot because the tip can continue to progress as new material is added to the end.”

Graduate students Joseph Greer, left, and Laura Blumenschein, right, work with Elliot Hawkes, a visiting assistant professor from the University of California, Santa Barbara, on a prototype of the vinebot. (Image credit: L.A. Cicero)

The group tested the benefits of this method for getting the robot from one place to another in several ways. It grew through an obstacle course, where it traveled over flypaper, sticky glue and nails and up an ice wall to deliver a sensor, which could potentially sense carbon dioxide produced by trapped survivors. It successfully completed this course even though it was punctured by the nails because the area that was punctured didn’t continue to move and, as a result, self-sealed by staying on top of the nail.

In other demonstrations, the robot lifted a 100-kilogram crate, grew under a door gap that was 10 percent of its diameter and spiraled on itself to form a free-standing structure that then sent out a radio signal. The robot also maneuvered through the space above a dropped ceiling, which showed how it was able to navigate unknown obstacles as a robot like this might have to do in walls, under roads or inside pipes. Further, it pulled a cable through its body while growing above the dropped ceiling, offering a new method for routing wires in tight spaces.

Difficult environments

“The applications we’re focusing on are those where the robot moves through a difficult environment, where the features are unpredictable and there are unknown spaces,” said Laura Blumenschein, a graduate student in the Okamura lab and co-author of the paper. “If you can put a robot in these environments and it’s unaffected by the obstacles while it’s moving, you don’t need to worry about it getting damaged or stuck as it explores.”

Some iterations of these robots included a control system that differentially inflated the body, which made the robot turn right or left. The researchers developed a software system that based direction decisions on images coming in from a camera at the tip of the robot.

A primary advantage of soft robots is that they can be safer than hard, rigid robots not only because they are soft but also because they are often lightweight. This is especially useful in situations where a robot could be moving in close quarters with a person. Another benefit, in the case of this robot, is that it is flexible and can follow complicated paths. This, however, also poses some challenges.

Joey Greer, a graduate student in the Okamura lab and co-author of the paper, said that controlling a robot requires a precise model of its motion, which is difficult to establish for a soft robot. Rigid robots, by comparison, are much easier to model and control, but are unusable in many situations where flexibility or safety is necessary. “Also, using a camera to guide the robot to a target is a difficult problem because the camera imagery needs to be processed at the rate it is produced. A lot of work went into designing algorithms that both ran fast and produced results that were accurate enough for controlling the soft robot,” Greer said.

Going big—and small

As it exists now, the scientists built the prototype by hand and it is powered through pneumatic air pressure. In the future, the researchers would like to create a version that would be manufactured automatically. Future versions may also grow using liquid, which could help deliver water to people trapped in tight spaces or to put out fires in closed rooms. They are also exploring new, tougher materials, like rip-stop nylon and Kevlar.

The vinebot is a tube of soft material that grows in one direction. (Image credit: L.A. Cicero)

The researchers also hope to scale the robot much larger and much smaller to see how it performs. They’ve already created a 1.8 mm version and believe small growing robots could advance medical procedures. In place of a tube that is pushed through the body, this type of soft robot would grow without dragging along delicate structures.

Okamura is a member of Stanford Bio-X and the Stanford Neurosciences Institute.

This research was funded by the National Science Foundation.

ALCOR laboratory’s BlueBotics Absolem in the field.

ALCOR Lab members describe their experience.

From September 23rd to October 2nd the first TRADR Joint Exercise (TJEx) took place at the Tremora hospital (ex American hospital of Calambrone) near Pisa, Italy, in cooperation with the TRADR partners and the firefighters from the Firebrigade of Pisa. Using a proven-in-practice user-centric design methodology, TRADR develops novel science and technology for human-robot teams to assist in disaster response efforts over multiple missions.Various kinds of robots collaborate with human team members to explore the environment, and gather physical samples. As part of the user-centric development process adopted by the TRADR project, the Joint Exercise plays an important role in establishing and maintaining close contact with the end-users. TRADR is an integrated research project funded by the EU FP7 Programme, ICT: Cognitive systems, interaction, robotics.

A firefighter wearing the Gaze Machine.

ALCOR Lab is one of the project partners and participated at the exercise with its own UGV and the Gaze Machine, which is a head mounted device that allows estimation at each instant as the wearer looks around the 3D environment. One of the main goals was to test the system components, and to run the system at the hospital site with the participation of end-users. We also collected various useful data and ran component-level experiments.

The first week was dedicated to the appropriate set-up and test of the integrated system. At the same time, various discussion groups examined specific issues such as planning, reasoning and robot behavior, user interfaces, database technology and architecture. During the first two days, we tested the functionality of the UAVs and the UGVs in terms of autonomous navigation, mapping in 3D and high-level planning. The third day, the firefighters from the Firebrigade of Pisa offered a demonstration of the canine search team. By the end of the first week, everything was perfectly planned and ready for the second phase, when the integrated system was run in the Tremora hospital together with the end-users.

Exercise of the Pisa USAR team.

The following days, we successfully performed missions with the complete system in simulated disaster scenario. In parallel, we worked with the firefighters to do a series of experiments using the Gaze Machine. Each firefighter wore the Gaze Machine and entered a partially collapsed building, examining the environment and communicating useful information to their colleagues outside the site. During the experiments we collected data about the areas that they visually inspected, together with the information they communicated to their colleagues.

Responsible for the multi-robot planning and of course the Gaze Machine, we are pleased that our lab has contributed to the successful outcome of the first TRADR Joint Exercise.

The TRADR team captured by the UAV.

Exercise of the Pisa USAR team.

Exercise of the Pisa USAR team.

The working environment outside the hospital.

Four researchers from Davide Scaramuzza’s Robotics and Perception Group at the University of Zurich, Switzerland, have won the prestigious KUKA Innovation Award (20.000 EUR) for their project “Collaboration of Flying and Ground Robots for Search-And-Rescue Missions” at the AUTOMATICA trade fair in Munich.

The ongoing project is part of the “Rescue Scenario” of NCCR Robotics, where researchers across Switzerland work together to develop robots that can be used to make disaster relief efforts safer and more efficient. This specific element of the Rescue Scenario involves teams of flying robots working together with ground robots. The idea behind the project is that, in a cluttered environment after a disaster, it may be too dangerous for human rescuers to enter a building, and so robots may be utilized. However, in such environments both flying and ground robots suffer from limitations: by working together, the flying robots can be used as the eye for the ground robot.

For the competition last week, the team presented the collaboration of a quadrotor and a KUKA youBot in a mock-up disaster scenario. The quadrotor is first sent to make a map of the scene, i.e., detecting obstacles and people who need help. Then, it commands the youBot to these people to deliver a first-aid package. From the air, it can tell the youBot where to go and which obstacles to remove on the way.

Have a look at the demo showed at AUTOMATICA!

The search and rescue team involved in the recent South Korean ferry tragedy has deployed a remotely-operated underwater robot to help in the investigation and hopeful search for possible survivors in what has been called the country’s worst maritime disaster in forty years. The Sewol ferry sunk off the coast of South Korea on April 14, 2014 carrying 476 passengers and crew on board; of these, 339 were high school students and teachers on a field trip. While 174 people have been rescued, divers’ efforts to locate the remaining victims have been hampered by strong currents, cold water and floating debris. An underwater ROV by Deep Trekker has been deployed to help rescuers assess the wreckage and the surrounding sea floor before sending divers into the ferry’s interior.

Hwang Dae-Sik, a diver at the scene, explained to Reuters the immense difficulty of his task: “We are trained for hostile environments, but it’s hard to be brave when we meet bodies in dark water … This is the most gruelling and heartbreaking job of my career.” According to the Reuters report, divers have been navigating the dark corridors of the ferry while carrying tethered oxygen tanks and communication lines that can snag on the sharp corners of the wreckage’s interior. Divers can only stay underwater for about an hour at a time.

“My heart goes out to the friends and families of these victims,” said President of Deep Trekker Sam Macdonald. “We hope our ROV can help keep divers from being put at further risk and that the families will get some closure.”

Websolus Co., Deep Trekker’s South Korean distributor, had a demo of the DTG2 ROV on hand and was able to quickly deploy the device and their expertise to the search and rescue team at the site of the accident. “We were fortunate that our dealers, who are also expert operators of the DTG2, were there to help,” said Amanda Coulas, Project Manager at Deep Trekker.

The DTG2 is a lightweight (8.5 kg) and portable remotely operated vehicle (ROV) designed for underwater exploration. It uses a patented internal pitching system that allows the ROV to move horizontally and vertically using only two thrusters. The independently mounted camera allows the operator to either set the camera to hold steady as the body rotates, or set the camera to move with the body as it pitches, making it possible to do detailed inspections. The DTG2’s power is contained within the submersible, and its low-drag tether has a diameter of just 4mm, allowing it to maneuver with minimal impact from the surface. Its die-cast aluminum casing is anodized and powder coated, making it suitable for both fresh and salt water use.

Until recently, most underwater ROVs have been too expensive and complicated to be easily deployed by rescue crew – many costing in the range of $25K – $50K and requiring skilled engineers to operate. But according to Macdonald, the search and rescue market is starting to realize that it can have an ROV solution within their budget. The Deep Trekker unit operating at the wreckage site in South Korea runs under $5000 USD and their DTG2 Worker model, which is equipped with a two-function grabber and allows operators to retrieve objects under water, is priced just under $8000 USD. Deep Trekker has ROVs working in 34 countries at present.

“In general, it only takes a few minutes to understand the controls, an hour or so to be good at them and maybe a weekend of practice to be an expert operator,” said Coulas. “Other ROVs require topside power – a generator – to send power down the tether to operate the ROV. This makes it much harder to transport the ROV in a zodiac or small rescue boat. Our ROV can operate 5-8 hours on one 3-hour charge.”

A Waterloo-based company, Deep Trekker got its start in the Great Lakes region of Ontario, Canada. “My partner and the engineering brains behind Deep Trekker Inc., Jeff Lotz, had developed an ROV for a college project about 14 years ago after he capsized his canoe and lost a lot of gear,” said Macdonald via email. “I had a similar situation in 2009 when I dropped a flashlight off of my boat, and began thinking about all the exploration that could be done in the Great Lakes if we had an ROV. Through a series of connections, the three partners in Deep Trekker Inc. got together and began exploring the possibility of an affordable, portable ROV that would be accessible to everyone. After meeting, conceptualizing and building for about 18 months, the first Deep Trekker voyage was made in Lake Huron.” The trio’s website was later discovered by an aquaculture equipment dealer in Norway, whose initial purchase of several of units helped to launched the company.

Search and rescue is a relatively new market for Deep Trekker, which in the past has concentrated on the aquaculture, commercial diving, recreation, and energy sectors. A Research and Markets report released in March estimates the global ROV market to be $1.2 billion in 2014, primarily driven by offshore drilling.

In applications such as exploration, search-and-rescue, or environmental monitoring, robots must be able to deal with very complex terrains, such as semi-collapsed buildings, deep caverns, or forests with heavy vegetation. Autonomous robots that can operate both in the air and on the ground are ideal for navigating these kinds of locations — for example, a robot may be needed to fly over a large forest, and then explore areas below the tree canopy. While many dual-locomotion systems already exist, most of these simply add specialized hardware for each locomotion method used (such as wings and wheels), adding both infrastructure and weight to the overall system, and hindering flight performance. Instead, DALER uses just one structure — the wing — to both walk and fly. This design approach is an example of “adaptive morphology”, where one part of a robot’s structure is adaptable and shared between different modes of operation.

The DALER is currently optimized for ground speed. The prototype shown in the video above can move forward at 0.2 m/s (0.7 BL/s), can rotate on spot at 25°/s, and is capable of walking with different gaits. Future iterations of the robot will focus on increasing the adaptability of the wings to improve forward flight, hover flight and displacement on the ground. For example, wings could be fully deployed for flying outdoors and reduced for hover flight and ground modes.

The DALER was developed at the Laboratory of Intelligent Systems at EPFL in Lausanne, Switzerland, where researchers investigate bio-inspired artificial intelligence, develop autonomous robotic systems, and address biological questions using computational and robotic models.

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NERVE, the New England Robotics Validation and Experimentation Center at UMass Lowell, when it opens tomorrow, will be one of three such facilities in the United States. Incorporating elements of NIST’s Standard Test Methods for Response Robots, the facility will present candidates for validation with a wide range of challenges to be overcome.

Via Robotics Business Review