Scientists at the University of California, Berkeley, designed a small robot capable of performing multiple vertical jumps in a row and jumping off walls—making it the most vertically agile robot yet.
The researchers defined agility as the height that something can reach with a single jump in Earth gravity, multiplied by the frequency at which that jump can be made.
A small, nocturnal primate called the galago inspired the robot’s design.
With the ability to jump five times in four seconds to a combined height of 8.5 meters, the galago is the most agile animal in nature. It can store energy in its tendons when in a crouched position, and therefore can jump to heights not achievable by muscle strength alone.
The UC Berkeley team’s robot—called Salto for saltatorial locomotion on terrain obstacles—mimics the energy-storing capabilities of the galago. Inside the robot is a spring, which loads using a leg mechanism to imitate the crouch position and store energy in the same way the galago does. By using this technique, the robot doesn’t need to “wind up” before a jump; as soon as it jumps, Salto is ready to jump again.
Ultimately, the researchers hope that one day, vertically agile robots can be used to jump around in rubble in search-and-rescue missions.
“By combining biologically inspired design principles with improved engineering technology, matching the agile performance of animals may not be that far off,” said Ronald Fearing, a professor of electrical engineering and computer sciences at UC Berkeley and a co-author of a paper outlining the discovery.
While the Salto robot achieved 78% of the vertical jumping ability of the galago, it’s important to note that other robots, such as the TAUB, a locust-inspired jumping robot, can jump higher in a single leap.
The research was published in the debut issue of the journal Science Robotics in December. The research was supported by the US Army Research Laboratory under the Micro Autonomous Systems and Technology Collaborative Technology Alliance, as well as by the National Science Foundation.
Explosives detector gets help from dog-like nose
One team of researchers discovered that to improve chemical detection devices, it doesn’t hurt to look at one of nature’s best chemical detectors for inspiration: the dog.
Researchers from National Institute of Standards and Technology (NIST), MIT’s Lincoln Laboratory and the US FDA found that affixing a 3D-printed dog nose to the end of a commercially available explosives detector improved odorant detection significantly.
Current chemical-detection technologies use continuous suction. The dog’s nose, however, detects scents by sniffing five times a second. The “active sniffing” of the dog can pull in aromas from further away than constant inhalation.
“The dog is an active aerodynamic sampling system that literally reaches out and grabs odorants,” said Matthew Staymates, a mechanical engineer and fluid dynamicist at NIST.
“It uses fluid dynamics and entrainment to increase its aerodynamic reach to sample vapors at increasingly large distances. Applying this bio-inspired design principle could lead to significantly improved vapor samplers for detecting explosives, narcotics, pathogens—even cancer.”
Using a 3D printer, Staymates and his colleagues created a replica of a female Labrador’s nose, including the shape, direction and spacing of the nostrils. Using schlieren imaging and high-speed video, the team confirmed that moving air through the artificial nose accurately represented sniffing from a real dog.
The group’s first set of experiments compared the artificial nose with detection devices that used continuous suction and found that the nose was four times better 10 centimeters away from the vapor source and 18 times better 20 centimeters away.
Based on that result, the team outfitted a commercially available vapor detector with a device that would enable it to recreate the sniffing. The result? The sniffer was 16 times more effective at a distance of four centimeters.
“Their incredible air-sampling efficiency is one reason why the dog is such an amazing chemical sampler,” Staymates said. “It’s just a piece of the puzzle. There’s lots more to be learned and to emulate as we work to improve the sensitivity, accuracy and speed of trace-detection technology.”
The group’s research was published in the journal Scientific Reports.
Metallic glass gears make for more precise robots
NASA’s Jet Propulsion Laboratory in Pasadena, CA, is working to develop a better gear using bulk metallic glass, a specially crafted alloy ideal for precision robotics. Technologist Douglas Hofmann of the JPL is the lead author of two recent papers examining the use of bulk metallic glasses (BMGs) in robotic gears.
Bulk metallic glasses have a unique atomic structure that has qualities of both metal and glass. BMGs start off with the organized, crystalline atomic structure of a metal. The material is then heated up into a liquid, creating a randomized atomic structure. Cool them rapidly, and this non-crystalline, “liquid” form is trapped in place—making it, technically, a glass.
Although BMGs were originally developed in California in 1960s and have been used to make everything from cellphones to golf clubs, “understanding how to design and implement them into structural hardware has proven elusive,” Hofmann said.
“Our team of researchers and engineers at JPL, in collaboration with groups at Caltech and UC San Diego, have finally put BMGs through the necessary testing to demonstrate their potential benefits for NASA spacecraft. These materials may be able to offer us solutions for mobility in harsh environments, like on Jupiter’s moon Europa.”
Bulk metallic glass has a low melting temperature and doesn’t get brittle in extreme cold, and gears made from BMG run “cold and dry.” Testing demonstrated strong torque and smooth turning without lubricant even at –200 degrees Celsius, making it perfect for robots that are sent to icy planets. The Mars Curiosity Rover expends energy heating up lubricant every time it needs to move.
“Being able to operate gears at the low temperature of icy moons, like Europa, is a potential game-changer for scientists,” said R. Peter Dillon, a technologist and program manager in JPL’s Materials Development and Manufacturing Technology Group. “Power no longer needs to be siphoned away from the science instruments for heating gearbox lubricant, which preserves precious battery power.”
The benefits of using bulk metallic glass in robots aren’t only seen in outer space. BMGs could be game-changing for reducing the cost of robots here on Earth, too.
Hofmann’s second paper looked at using BMGs to manufacture strain wave gears, a type of gear that includes a metal ring that flexes as the gear spins. These gears are tricky to mass produce, but they’re necessary for advanced robots, especially humanoid ones—and they’re often the robot’s most expensive part.
The research group found that BMGs not only allow these gears to perform at low temperatures but also can be produced at a fraction of the cost of their steel counterparts.
“Mass producing strain wave gears using BMGs may have a major impact on the consumer robotics market,” Hofmann said. “The performance at low temperatures for JPL spacecraft and rovers seems to be a happy added benefit.”
Industrial exoskeleton reduces injury risk
SuitX, a California-based robotics company that designs and makes medical and industrial exoskeletons, introduced its MAX industrial exoskeleton at the end of last year.
The MAX exoskeleton consists of three separate modules: the backX, shoulderX and legX. All three modules can be worn together or separately, depending on need. The backX reduces forces on the wearer’s lower back, the shoulder reduces forces at the shoulder, allowing the wearer to perform lifting tasks for longer periods of time and with less effort, and the legX reduces strain on the knees and quadriceps, allowing the wearer to squat repeatedly or for long period of time.
“The MAX solution is designed for unstructured workplaces where no robot can work as efficiently as a human worker. Our goal is to augment and support workers who perform demanding and repetitive tasks in unstructured workplaces in order to prevent and reduce injuries,” suitX CEO Homayoon Kazerooni said.
Kazerooni is also a professor of mechanical engineering at the University of California, Berkeley. SuitX was founded based on research rooted in the Robotics and Human Engineering Lab, where he is the director, at the university.
“We have created responsive and affordable technologies to augment workers’ strength while leaving the worker in control of the operation,” he said. “MAX is designed to support workers during the repetitive tasks that most frequently cause injury. It’s not only lifting 75 pounds that can hurt your back; it is also lifting 20 pounds repeatedly throughout the day that will lead to injury.”
Initial research to develop MAX was provided by various sources, including a grand from the National Science Foundation under a National Robotics Initiative program the White House put forth in 2011.
Printable electronics at a bargain price
What if you could slap a sticker onto your daily latte and get an instant read on its temperature? What if your produce had packaging that indicated exactly when it was about to go bad? Imagine this same technology on a window inside your home, displaying the day’s forecast by measuring the conditions outside.
Such technology has been a pipedream of scientists for some time. Coming up with a practical, inexpensive yet precise solution has been the challenge. Attempts to print these electronic surfaces using inkjet printing or stamping techniques have produced mixed results since these methods are difficult to control at a small scale. Ink spills over the borders or prints are uneven.
Researchers at MIT invented a fast, precise process that could make these printable electronic stamps inexpensive
to make. The key lies in forests of carbon nanotubes, which can accurately print electronic inks onto rigid and flexible surfaces.
The MIT group, led by A John Hart, has been working with carbon nanotubes for some time.
“It’s somewhat serendipitous that the solution to high-resolution printing of electronics leverages our background in making carbon nanotubes for many years,” Hart said. “The forests of carbon nanotubes can transfer ink onto a surface like massive numbers of tiny pen quills.”
The team designed a “nanoporous” stamp—more spongy than rubber and the size of a pinky fingernail, with features smaller than the width of a human hair—that lets the ink flow through the stamp and onto the surface to be printed.
To make the stamps, Hart’s group used its previously developed techniques to grow carbon nanotubes on the surface of silicon in various patterns, and then coated the nanotubes with a polymer layer in order to make sure the nanotubes would not shrink after the ink was stamped. They then infused the stamp with electronic ink containing nanoparticles like silver, zinc oxide or semiconductor quantum dots.
The group created a printing machine with a motorized roller and attached it to various flexible substrates. The researchers fixed each stamp onto a platform attached to a spring, which helped control the force used to press the stamp against the substrate—essential for printing tiny yet precise patterns.
“We found, limited by the motor we used in the printing system, we could print at 200 millimeters per second, continuously, which is already competitive with the rates of industrial printing technologies,” Hart said. “This, combined with a tenfold improvement in the printing resolution that we demonstrated, is encouraging.”
The ink patterns proved highly-conductive, and going forward, the team plans to investigate the possibility of fully printed electronics.
The research was published in the journal Science Advances. It was supported in part by the National Science Foundation and the MIT Energy Initiative.