New Mars rover may swim by means of sand like a desert lizard

To successfully journey on Mars, rovers must cope with lots of sand. German engineers have created a brand new form of floor rover that makes use of swimming motions to push by means of sand that will in any other case trigger the  wheels to get caught. Its inspiration: the African sandfish (Scincus scincus), a lizard identified for burrowing into the Sahara Desert and actually swimming by means of its sand like a fish. It’s one of many animal kingdom’s strangest strategies of propulsion, however it could assist form the way forward for Mars exploration.

A video of the rover, released this week by the University of Würzburg, reveals a mini-fridge-sized, silver rover making its method by means of a sandy, Martian-mimicking check flooring. Rather than rolling ahead, every of its 4 wheels cuts by means of the sand in what appears to be like like a figure-eight movement. The rover pushes on a number of yards after which cuts a nook and returns to the place it began.

Sandfish-inspired rover

“The wheels mimic the animal’s [sandfish’s]characteristic interaction with the ground, generating both longitudinal and lateral forces,” University of Würzburg researcher Amenosis Lopez said in a statement. “The rover leaves sinusoidal tracks in the sand.” 

The sandfish: nature’s cute resolution to slippery sand 

Though most individuals seemingly affiliate house rovers with spherical wheels or tracks harking back to these on WALL-E, neither design is right for coping with Mars’s uniquely harsh and sandy setting. Sand is exclusive as a result of it’s a cloth with each stable and liquid-like qualities. On prime of sand’s blended texture, rovers roaming on the Red Planet need to cope with steep slopes and uneven terrain, the place various ranges of slipperiness could cause imbalance. Patches of softer sand are additionally a nightmare for wheels, making the prospect of a rover getting caught by no means removed from thoughts

But nature found out an answer to this difficulty hundreds of thousands of years in the past, and it’s referred to as the sandfish. Contrary to its identify, the Sahara Desert native is a lizard within the skink household. Above floor, the sandfish makes use of its tiny legs to scrabble round a lot the identical as any lizard. Things get extra fascinating when it burrows down into the sand. X-ray imaging reveals  the sandfish propelling itself ahead underneath the sand, utilizing a robust waving movement to generate thrust and overcome drag. The end result appears to be like like an animal swimming by means of the sand, remarkably equally to how a fish would oscillate its physique to maneuver by means of water

Sandfish

Engineers at Georgia Tech took these observations and used them to create their own sandfish robot in 2011. Testing with their robots confirmed that the little lizard’s oddly wedged formed head can also assist it generate carry forces and extra simply swim by means of sand. 

Georgia Tech Sandfish Robot

Sink or swim: new rover did each 

Researchers engaged on the sandfish-inspired robotic stated it outperformed a wheeled model when navigating by means of a sandy check monitor. Where the spherical wheels would wobble and weave, the oscillating wheels stayed comparatively secure. That’s to not say the brand new strategy labored proper out of the gate. Early fashions of the design have been reportedly so heavy that the  rover actually sank into the sand. The group went again to the drafting board and made a second model, this time growing every wheel’s width and decreasing general mass

It’s unlikely these oddball new wheels will turn into the primary chassis system for NASA rovers, a minimum of not within the instant future. More work nonetheless must be executed to extend their general controllability and account for slippage that may happen in sophisticated, real-world environments. There are additionally the added variables of accounting for scientific devices and different cargo a rover might need to hold. 

More than something, the wheel design is a testomony to the sandfish’s innate ingenuity and evolutionary presents. Many scientists solely not too long ago started to actually respect these traits and what different expertise they might encourage. 

 

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