Tag Archives: both
#437747 High Performance Ornithopter Drone Is ...
The vast majority of drones are rotary-wing systems (like quadrotors), and for good reason: They’re cheap, they’re easy, they scale up and down well, and we’re getting quite good at controlling them, even in very challenging environments. For most applications, though, drones lose out to birds and their flapping wings in almost every way—flapping wings are very efficient, enable astonishing agility, and are much safer, able to make compliant contact with surfaces rather than shredding them like a rotor system does. But flapping wing have their challenges too: Making flapping-wing robots is so much more difficult than just duct taping spinning motors to a frame that, with a few exceptions, we haven’t seen nearly as much improvement as we have in more conventional drones.
In Science Robotics last week, a group of roboticists from Singapore, Australia, China, and Taiwan described a new design for a flapping-wing robot that offers enough thrust and control authority to make stable transitions between aggressive flight modes—like flipping and diving—while also being able to efficiently glide and gently land. While still more complex than a quadrotor in both hardware and software, this ornithopter’s advantages might make it worthwhile.
One reason that making a flapping-wing robot is difficult is because the wings have to move back and forth at high speed while electric motors spin around and around at high speed. This requires a relatively complex transmission system, which (if you don’t do it carefully), leads to weight penalties and a significant loss of efficiency. One particular challenge is that the reciprocating mass of the wings tends to cause the entire robot to flex back and forth, which alternately binds and disengages elements in the transmission system.
The researchers’ new ornithopter design mitigates the flexing problem using hinges and bearings in pairs. Elastic elements also help improve efficiency, and the ornithopter is in fact more efficient with its flapping wings than it would be with a rotary propeller-based propulsion system. Its thrust exceeds its 26-gram mass by 40 percent, which is where much of the aerobatic capability comes from. And one of the most surprising findings of this paper was that flapping-wing robots can actually be more efficient than propeller-based aircraft.
One of the most surprising findings of this paper was that flapping-wing robots can actually be more efficient than propeller-based aircraft
It’s not just thrust that’s a challenge for ornithopters: Control is much more complex as well. Like birds, ornithopters have tails, but unlike birds, they have to rely almost entirely on tail control authority, not having that bird-level of control over fine wing movements. To make an acrobatic level of control possible, the tail control surfaces on this ornithopter are huge—the tail plane area is 35 percent of the wing area. The wings can also provide some assistance in specific circumstances, as by combining tail control inputs with a deliberate stall of the things to allow the ornithopter to execute rapid flips.
With the ability to take off, hover, glide, land softly, maneuver acrobatically, fly quietly, and interact with its environment in a way that’s not (immediately) catastrophic, flapping-wing drones easily offer enough advantages to keep them interesting. Now that ornithopters been shown to be even more efficient than rotorcraft, the researchers plan to focus on autonomy with the goal of moving their robot toward real-world usefulness.
“Efficient flapping wing drone arrests high-speed flight using post-stall soaring,” by Yao-Wei Chin, Jia Ming Kok, Yong-Qiang Zhu, Woei-Leong Chan, Javaan S. Chahl, Boo Cheong Khoo, and Gih-Keong Lau from from Nanyang Technological University in Singapore, National University of Singapore, Defence Science and Technology Group in Canberra, Australia, Qingdao University of Technology in Shandong, China, University of South Australia in Mawson Lakes, and National Chiao Tung University in Hsinchu, Taiwan, was published in Science Robotics. Continue reading
Posted in Human Robots
#437741 CaseCrawler Adds Tiny Robotic Legs to ...
Most of us have a fairly rational expectation that if we put our cellphone down somewhere, it will stay in that place until we pick it up again. Normally, this is exactly what you’d want, but there are exceptions, like when you put your phone down in not quite the right spot on a wireless charging pad without noticing, or when you’re lying on the couch and your phone is juuust out of reach no matter how much you stretch.
Roboticists from the Biorobotics Laboratory at Seoul National University in South Korea have solved both of these problems, and many more besides, by developing a cellphone case with little robotic legs, endowing your phone with the ability to skitter around autonomously. And unlike most of the phone-robot hybrids we’ve seen in the past, this one actually does look like a legit case for your phone.
CaseCrawler is much chunkier than a form-fitting case, but it’s not offensively bigger than one of those chunky battery cases. It’s only 24 millimeters thick (excluding the motor housing), and the total weight is just under 82 grams. Keep in mind that this case is in fact an entire robot, and also not at all optimized for being an actual phone case, so it’s easy to imagine how it could get a lot more svelte—for example, it currently includes a small battery that would be unnecessary if it instead tapped into the phone for power.
The technology inside is pretty amazing, since it involves legs that can retract all the way flat while also supporting a significant amount of weight. The legs work sort of like your legs do, in that there’s a knee joint that can only bend one way. To move the robot forward, a linkage (attached to a motor through a gearbox) pushes the leg back against the ground, as the knee joint keeps the leg straight. On the return stroke, the joint allows the leg to fold, making it compliant so that it doesn’t exert force on the ground. The transmission that sends power from the gearbox to the legs is just 1.5-millimeter thick, but this incredibly thin and lightweight mechanical structure is quite powerful. A non-phone case version of the robot, weighing about 23 g, is able to crawl at 21 centimeters per second while carrying a payload of just over 300 g. That’s more than 13 times its body weight.
The researchers plan on exploring how robots like these could make other objects movable that would otherwise not be. They’d also like to add some autonomy, which (at least for the phone case version) could be as straightforward as leveraging the existing sensors on the phone. And as to when you might be able to buy one of these—we’ll keep you updated, but the good news is that it seems to be fundamentally inexpensive enough that it may actually crawl out of the lab one day.
“CaseCrawler: A Lightweight and Low-Profile Crawling Phone Case Robot,” by Jongeun Lee, Gwang-Pil Jung, Sang-Min Baek, Soo-Hwan Chae, Sojung Yim, Woongbae Kim, and Kyu-Jin Cho from Seoul National University, appears in the October issue of IEEE Robotics and Automation Letters.
< Back to IEEE Journal Watch Continue reading
Posted in Human Robots
#437735 Robotic Chameleon Tongue Snatches Nearby ...
Chameleons may be slow-moving lizards, but their tongues can accelerate at astounding speeds, snatching insects before they have any chance of fleeing. Inspired by this remarkable skill, researchers in South Korea have developed a robotic tongue that springs forth quickly to snatch up nearby items.
They envision the tool, called Snatcher, being used by drones and robots that need to collect items without getting too close to them. “For example, a quadrotor with this manipulator will be able to snatch distant targets, instead of hovering and picking up,” explains Gwang-Pil Jung, a researcher at Seoul National University of Science and Technology (SeoulTech) who co-designed the new device.
There has been other research into robotic chameleon tongues, but what’s unique about Snatcher is that it packs chameleon-tongue fast snatching performance into a form factor that’s portable—the total size is 12 x 8.5 x 8.5 centimeters and it weighs under 120 grams. Still, it’s able to fast snatch up to 30 grams from 80 centimeters away in under 600 milliseconds.
Image: SeoulTech
The fast snatching deployable arm is powered by a wind-up spring attached to a motor (a series elastic actuator) combined with an active clutch. The clutch is what allows the single spring to drive both the shooting and the retracting.
To create Snatcher, Jung and a colleague at SeoulTech, Dong-Jun Lee, set about developing a spring-like device that’s controlled by an active clutch combined with a single series elastic actuator. Powered by a wind-up spring, a steel tapeline—analogous to a chameleon’s tongue—passes through two geared feeders. The clutch is what allows the single spring unwinding in one direction to drive both the shooting and the retracting, by switching a geared wheel between driving the forward feeder or the backward feeder.
The end result is a lightweight snatching device that can retrieve an object 0.8 meters away within 600 milliseconds. Jung notes that some other, existing devices designed for retrieval are capable of accomplishing the task quicker, at about 300 milliseconds, but these designs tend to be bulky. A more detailed description of Snatcher was published July 21 in IEEE Robotics and Automation Letters.
Photo: Dong-Jun Lee and Gwang-Pil Jung/SeoulTech
Snatcher’s relative small size means that it can be installed on a DJI Phantom drone. The researchers want to find out if their system can help make package delivery or retrieval faster and safer.
“Our final goal is to install the Snatcher to a commercial drone and achieve meaningful work, such as grasping packages,” says Jung. One of the challenges they still need to address is how to power the actuation system more efficiently. “To solve this issue, we are finding materials having high energy density.” Another improvement is designing a chameleon tongue-like gripper, replacing the simple hook that’s currently used to pick up objects. “We are planning to make a bi-stable gripper to passively grasp a target object as soon as the gripper contacts the object,” says Jung.
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Posted in Human Robots
#437733 Video Friday: MIT Media Lab Developing ...
Video Friday is your weekly selection of awesome robotics videos, collected by your Automaton bloggers. We’ll also be posting a weekly calendar of upcoming robotics events for the next few months; here’s what we have so far (send us your events!):
AWS Cloud Robotics Summit – August 18-19, 2020 – [Online Conference]
CLAWAR 2020 – August 24-26, 2020 – [Online Conference]
ICUAS 2020 – September 1-4, 2020 – Athens, Greece
ICRES 2020 – September 28-29, 2020 – Taipei, Taiwan
AUVSI EXPONENTIAL 2020 – October 5-8, 2020 – [Online Conference]
IROS 2020 – October 25-29, 2020 – Las Vegas, Nev., USA
ICSR 2020 – November 14-16, 2020 – Golden, Colo., USA
Let us know if you have suggestions for next week, and enjoy today’s videos.
Very impressive local obstacle avoidance at a fairly high speed on a small drone, both indoors and outdoors.
[ FAST Lab ]
Matt Carney writes:
My PhD at MIT Media Lab has been the design and build of a next generation powered prosthesis. The bionic ankle, named TF8, was designed to provide biologically equivalent power and range of motion for plantarflexion-dorsiflexion. This video shows the process of going from a blank sheet of paper to people walking on it. Shown are three different people wearing the robot. About a dozen people have since been able to test the hardware.
[ MIT ]
Thanks Matt!
Exciting changes are coming to the iRobot® Home App. Get ready for new personalized experiences, improved features, and an easy-to-use interface. The update is rolling out over the next few weeks!
[ iRobot ]
MOFLIN is an AI Pet created from a totally new concept. It possesses emotional capabilities that evolve like living animals. With its warm soft fur, cute sounds, and adorable movement, you’d want to love it forever. We took a nature inspired approach and developed a unique algorithm that allows MOFLIN to learn and grow by constantly using its interactions to determine patterns and evaluate its surroundings from its sensors. MOFLIN will choose from an infinite number of mobile and sound pattern combinations to respond and express its feelings. To put it in simple terms, it’s like you’re interacting with a living pet.
You lost me at “it’s like you’re interacting with a living pet.”
[ Kickstarter ] via [ Gizmodo ]
This video is only robotics-adjacent, but it has applications for robotic insects. With a high-speed tracking system, we can now follow insects as they jump and fly, and watch how clumsy (but effective) they are at it.
[ Paper ]
Thanks Sawyer!
Suzumori Endo Lab, Tokyo Tech has developed self-excited pneumatic actuators that can be integrally molded by a 3D printer. These actuators use the “automatic flow path switching mechanism” we have devised.
[ Suzimori Endo Lab ]
Quadrupeds are getting so much better at deciding where to step rather than just stepping where they like and trying not to fall over.
[ RSL ]
Omnidirectional micro aerial vehicles are a growing field of research, with demonstrated advantages for aerial interaction and uninhibited observation. While systems with complete pose omnidirectionality and high hover efficiency have been developed independently, a robust system that combines the two has not been demonstrated to date. This paper presents the design and optimal control of a novel omnidirectional vehicle that can exert a wrench in any orientation while maintaining efficient flight configurations.
[ ASL ]
The latest in smooth humanoid walking from Dr. Guero.
[ YouTube ]
Will robots replace humans one day? When it comes to space exploration, robots are our precursors, gathering data to prepare humans for deep space. ESA robotics engineer Martin Azkarate discusses some of the upcoming missions involving robots and the unique science they will perform in this episode of Meet the Experts.
[ ESA ]
The Multi-robot Systems Group at FEE-CTU in Prague is working on an autonomous drone that detects fires and the shoots an extinguisher capsule at them.
[ MRS ]
This experiment with HEAP (Hydraulic Excavator for Autonomous Purposes) demonstrates our latest research in on-site and mobile digital fabrication with found materials. The embankment prototype in natural granular material was achieved using state of the art design and construction processes in mapping, modelling, planning and control. The entire process of building the embankment was fully autonomous. An operator was only present in the cabin for safety purposes.
[ RSL ]
The Simulation, Systems Optimization and Robotics Group (SIM) of Technische Universität Darmstadt’s Department of Computer Science conducts research on cooperating autonomous mobile robots, biologically inspired robots and numerical optimization and control methods.
[ SIM ]
Starting January 1, 2021, your drone platform of choice may be severely limited by the European Union’s new drone regulations. In this short video, senseFly’s Brock Ryder explains what that means for drone programs and operators and where senseFly drones fit in the EU’s new regulatory framework.
[ SenseFly ]
Nearly every company across every industry is looking for new ways to minimize human contact, cut costs and address the labor crunch in repetitive and dangerous jobs. WSJ explores why many are looking to robots as the solution for all three.
[ WSJ ]
You’ll need to prepare yourself emotionally for this video on “Examining Users’ Attitude Towards Robot Punishment.”
[ ACM ]
In this episode of the AI Podcast, Lex interviews Russ Tedrake (MIT and TRI) about biped locomotion, the DRC, home robots, and more.
[ AI Podcast ] Continue reading
Posted in Human Robots