Flying geckos are able to use their tails to stabilise their landings after crashing into trees at speeds of up to 13 miles per hour, a new study has revealed.
A drone based on the remarkable crash landing capabilities of the small lizard opens the door to future airborne robots that can land on walls or upside down, according to the developers at the Max Planck Institute for Intelligent Systems in Stuttgart.
They discovered that the colourful creatures use their tail to stabilise themselves after gliding head first into a tree trunk, stopping them falling to the ground.
Corresponding author Dr Ardian Jusufi said structures similar to gecko tails could stabilise drones during a landing on a vertical surface.
This could lead to robots that can land in inaccessible places, helping search and rescue after a landslide or building collapse, or during military operations, they said.
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Flying geckos are able to use their tails to stabilise their landings after crashing into trees at speeds of up to 13 miles per hour, a new study has revealed
A drone based on the remarkable crash landing capabilities of the small lizard opens the door to future airborne robots that can land on walls or upside down, according to the developers at the Max Planck Institute for Intelligent Systems in Stuttgart
THE MULTI-TALENTED GECKO: FROM WALKING ON WATER TO GLIDING
Geckos’ climbing abilities give them agility rarely surpassed in nature.
With adhesive lamellae on their feet, geckos can climb up smooth vertical surfaces with ease.
These amazing creatures can even move on a ceiling hanging upside down thanks to their sticky feet.
Their ability to run on water is another superpower for these small lizards.
Now another can be added – the ability to crash into a tree at high speed without getting hurt.
Recent studies revealed they can use their tail like a fifth leg to stabilise themselves after gliding from one tree to another at speed.
Geckos are ‘multi-talented superheroes’ according to the German researchers, who said they can climb up smooth vertical surfaces, walk upside down on a ceiling, run on water and now land on a vertical surface after a 13 mile per hour glide.
Co-author Dr Robert Siddall said nature has many unexpected, elegant solutions to engineering problems.
‘This is wonderfully illustrated by the way geckos can use their tails to turn a head-first collision into a successful perching manoeuvre.
‘Landing from flight is difficult. We hope our findings will lead to new techniques for robot mobility – sometimes crashes are helpful.’
Two soft-gecko like machines were built by the team – one with a tail and the other without to see how important the tail was to its stability.
During trials, the former landed on a Velcro-covered vertical surface 55 per cent of the time – a success rate four times better than the latter.
The researchers first compiled video footage showing geckos are capable gliders – despite having no specialisations for flight.
It adds another string to their bow of incredible superpowers. They have legendary agility rarely surpassed in nature.
Highly adhesive foot pads, called lamellae, enable them to scale smooth vertical surfaces with ease – or move on a ceiling hanging upside down.
They discovered that the colourful creatures use their tail to stabilise themselves after gliding head first into a tree trunk, stopping them falling them to the ground
An image sequence of the fall arresting response. Corresponding author Dr Ardian Jusufi said structures similar to gecko tails could stabilise drones during a landing on a vertical surface
The high-speed cameras recorded wild geckos jumping off a platform 25 feet off the ground and gliding towards a nearby tree.
Close-range analysis revealed they landed at 13 mph by crashing head-first and swinging their torsos and tails down against the trunk.
A car travelling at the same speed would be heavily dented – but they didn’t suffer a scratch, and never lost grip with their forefeet as their torso and head swung back.
Close-range analysis revealed they landed at 13 mph by crashing head-first and swinging their torsos and tails down against the trunk
Ardian Jusufi with a soft gecko-inspired robot. Two soft-gecko like machines were built by the team – one with a tail and the other without to see how important the tail was to its stability
CREATING A ‘DIGITAL GECKO’ TO STUDY THE SMALL LIZARDS
The scientists created a physical model of a gecko to better understand the forces the animal experiences.
Their gecko-inspired robot features a soft torso, where the tail can be taken off and put back on.
When the front foot hits a surface, the robot is programmed to bend its tail just like the reflex seen when the gecko crashes into a trail.
The information is processed via a microcontroller on the shoulder.
This signal activates the motor to pull on a tendon and hence pushes the tail into the wall to slow the head over heels pitchback.
They tested it by catapulting a soft robotic lizard onto a wall with an embedded force-sensitive scale.
To simulate a tree trunk, they lined the wall with felt and the velcro-lined feet of the robot latched on.
The robot hit the force plate as abruptly as the geckos hitting the tree, tilting back its torso at a right angle to the surface.
The roboticists then measured the force the front and back feet of the robot endured upon impact.
The longer the tail, they discovered, the lower the force pulling the back feet away from the surface.
The lower that force, the easier it is for the robot to hold on.
Without a tail, however, the forces on the back feet become too high – the robot loses grip, bounces off, and falls.
Falling was prevented by pushing their tail against the tree ‘like a fifth leg’ – and then stabilising their footing.
The robots were then launched from a catapult to mimic the high-speed landing from a glide and only the one with a tail worked consistently.
Dr Jusufi said: ‘The results from field observations, as well as computer models, indicate the tail increases landing stability and success by reducing the foot forces required to keep the robot attached to the vertical surface.’
The Asian flat-tailed gecko lives in the jungle and can jump or glide many feet from one tree to the next to avoid predators.
It is still accelerating when it lands – so everything happens in the blink of an eye.
The team, which included biologists in the US, hope the discovery will lead to a new generation of super drones.
Dr Jusufi said: ‘This field discovery on the perching behaviour of geckos has important implications for our understanding of tails as multi-functional appendages that animals can rely on.
‘Ranging from inertial to contact tails, they facilitate the most extreme transitions, such as from gliding flight to collision with a wall.
‘One of the most dramatic transitions we can think of in multi-modal locomotion is to alight on a vertical surface from high-speed gliding flight to a standstill.’
It is the first time the amazing animal’s gliding behaviour has been quantified, as filming the small, camouflaged lizard int he rainforest is tough.
‘Previously contact tails were thought to be used to maintain grip during rapid wall-running,’ said Dr Jusufi.
‘The findings presented here suggest that geckos exhibit exaptation of the behaviour to improve the success of landing in the wake of their directed aerial descent.’
He added: ‘With the robot, we were able to measure something we could not with geckos in the field.
‘The wall reaction forces at the impact upon landing confirmed that the tail is an essential part facilitating the landing in subcritical glides.
‘Our soft robotic lander not only helps to make an impact in another field, but it can also help improve robot locomotion by increasing robustness and simplifying control.’
The study is published in the journal Communications Biology.
BOSTON DYNAMICS’ SPOT
Boston Dynamics first showed off SpotMini, the most advanced robot dog ever created, in a video posted in November 2017.
The firm, best known for Atlas, its 5 foot 9 (1.7 metre) humanoid robot, has revealed a new ‘lightweight’ version of its robot Spot Mini.
The robotic canine was shown trotting around a yard, with the promise that more information from the notoriously secretive firm is ‘coming soon’.
‘SpotMini is a small four-legged robot that comfortably fits in an office or home’ the firm says on its website.
It weighs 25 kg (55 lb), or 30 kg (66 lb) when you include the robotic arm.
SpotMini is all-electric and can go for about 90 minutes on a charge, depending on what it is doing, the firm says, boasting ‘SpotMini is the quietest robot we have built.’
SpotMini was first unveiled in 2016, and a previous version of the mini version of spot with a strange extendable neck has been shown off helping around the house.
In the firm’s previous video, the robot is shown walking out of the firm’s HQ and into what appears to be a home.
There, it helps load a dishwasher and carries a can to the trash.
It also at one point encounters a dropped banana skin and falls dramatically – but uses its extendable neck to push itself back up.
‘SpotMini is one of the quietest robots we have ever built, the firm says, due to its electric motors.
‘It has a variety of sensors, including depth cameras, a solid state gyro (IMU) and proprioception sensors in the limbs.
‘These sensors help with navigation and mobile manipulation.
‘SpotMini performs some tasks autonomously, but often uses a human for high-level guidance.’