Tech Radar | What caught our attention outside the world of oil and gas this month

By air and by sea

US start-up Natilus intends to use large aerial drones to speed up cargo deliveries across oceans.

The company is currently evaluating a prototype design for an unmanned seaplane drone, which could eventually carry over 100 tonnes of cargo across ocean delivery routes, beating cargo ships by weeks but up to 17 times cheaper than a 747 jet.

Founded in 2014, the company closed a new round of seed funding in November 2017. 

In December the company planned to test a craft with a 9-metre wingspan in San Francisco, to prove its capabilities for water take-off, cruising at around 200 feet and landing. Further testing overseen by the Federal Aviation Administration is slated for 2018.

By 2020 it hopes to be flying small versions of the craft which could carry 2 tonnes of cargo between regional airports. Its goal is to sell the craft to major logistics firms like UPS and DHL, who are keen to offer faster delivery times for premium services. The autonomous nature of the craft could also enable longer flight times, while its simplicity is aimed at making it cheaper to maintain.

Small drones are already cost-effective ways of delivering goods to remote infrastructure, but craft such as these could pave the way for larger supplies – industry logistics firms should keep a lookout.

A sucker every minute

Octopi are known for their dextrous tentacles, which offer a level of mobility and suction that most robotic systems have yet to master. However, a diverse team from UK and Italian universities, and led by Dr Sina Sareh at the Royal College of Art, has sought to design a synthetic system that could mimic these actions. 

In a paper published in Royal Society journal Interface last year, they describe the design and production of a “robotic anchoring module” containing sensors, which could be integrated into robots to enable greater mobility, station-keeping or even to manipulate objects.

After studying the grooved suckers of octopi the team used CAD and 3D printing to produce a silicon module, which could be activated via a vacuum pump. A light-sensitive sensor and fibre-optic link was also included in the model, allowing the sucker to sense tactile and proximity information such as the firmness of an object, the distance from the sucker and physical loads.

When not activated, the sucker module will also collapse, making it ideal for applications where robots must handle particularly sensitive or fragile objects. In their paper, the team suggested it could be used as “a soft sensory–physical grasper in robotic pick and place applications.”

Following work on this prototype, Sareh and his team said that future work would further develop the concept using computational models and prototypes of the proposed anchoring system for use in multi-anchor robotic systems, suitable for medical and industrial applications.

http://rsif.royalsocietypublishing.org/content/14/135/20170395 

Light after shark

A new quantum material being tested by Purdue University is able to detect minute changes in electric fields in water. The technology, which mimics a shark’s ability to sense prey, has been successfully lab-tested in cold and saltwater conditions, and could be used in marine biology and maritime applications. 

Led by Purdue postdoctoral research associate Zhen Zhang and graduate student Derek Schwanz, the study was inspired by the “ampullae of Lorenzini” – an ion-conducting, jelly-filled organ in sharks which allows a membrane to detect bioelectric fields. 

The team’s material, samarium nitrate, enables quantum interactions and is an ideal conductor of photons. This allows it to undergo a phase change, moving from a conductor to an insulator – enabling its use as a detector – and to send photons back and forth into the surrounding water.

“We show that these sensors can detect electrical potentials well below one volt, on the order of millivolts, which is comparable to electric potentials emanated by marine organisms. The material is very sensitive. We calculated the detection distance of our device and [have found] a similar length scale to what has been reported for electroreceptors in sharks,” commented Purdue professor of materials engineering and co-author Shriram Ramanathan.

Moreover, because the material is already oxidised, it will not corrode in a seawater environment.

The material’s optical properties also enable additional sensing. As it becomes more insulating, it also becomes more transparent, and as Ramanathan explains: “If the material transmits light differently, then you can use light as a probe to study the property of the material and that is very powerful. Now you have multiple ways to study a material, electrically and optically.”

Having tested the device in the lab, the group now intends to study the material in real ocean conditions and to work with biologists to investigate further applications.

[Caption: Optical image of nickelate material after treatment in water. The optical transparency is
sensitive to the water environmental conditions. Marshall Farthing/Purdue University]

Hygropower

Researchers from South Korea have designed moving micro-robots powered only by water. 

The tiny craft use a bilayer structure inspired by plants and seeds which are capable of motion. In this case, a series of ratchets attached to a water-sensitive material enable hygroscopic actuation, and this propels the robot along. Requiring no additional power, they could be used in a wide variety of military and industrial applications, particularly in hazardous environments where batteries may be unsuitable. 

Dubbed “hygrobots” by the team, the creations use nanofibres produced by directional electrospinning, which swell and shrink in response to changes in humidity. In practical terms, one layer of the robot will change swell and change shape when in contact with moisture, but return to its original shape when the moisture evaporates. 
The team managed to produce robots which mimicked the motions of worms, snakes and snails.

“The ability of the hygrobot to propel itself on a moist surface without an artificial supply of energy opens a wide window of practical applications. In particular, a rich variety of biomedical functions can be performed by the hygrobot on moist human skin,” the authors from Seoul National University reported in their paper. In one demonstration, a hygrobot was used to administer antibiotics across a petri dish, all under its own propulsion.

They also believe that if these materials were fabricated to respond to gases rather than water, they could also be used to build sensors with mechanical responses according to the concentration of specific gas molecules (or indeed other chemicals).