Beyond biomimicry: Scientists find better-than-nature run style for six-legged robots

Researchers have found a running style for six-legged robots that significantly improves on the traditional nature-inspired method of movement.

The research, conducted by scientists at the École Polytechnique Fédérale de Lausanne (EPFL) and the University of Lausanne (UNIL) in Switzerland, found that as long as the robots are not equipped with insect-like adhesive pads, it is faster for them to move with only two legs on the ground at any given time.

Robotics has in the past few years made heavy use of biomimicry – the practice of mimicking natural systems – resulting in six-legged robots being designed to move like insects. In nature, insects use what is known as a tripod gait, where they have three legs on the ground at a time, so it had been assumed that this was the most efficient way for similarly legged robots to move.

However, by undertaking a series of computer simulations, tests on robots and experiments on Drosophila melanogaster – better known as the common fruit fly – the scientists found that the two-legged approach, which they have dubbed the bipod gait, results in faster and more efficient movement.

The core goal of the research, which is published today in the journal Nature Communications, was to confirm whether the long-held assumption that a tripod gait was best was indeed correct.

“We wanted to determine why insects use a tripod gait and identify whether it is, indeed, the fastest way for six-legged animals and robots to walk,” said Pavan Ramdya, study co-lead and corresponding author.

Initially, this involved the use of a simulated insect model based on the common fruit fly and an algorithm designed to mimic different evolutionary stages. This algorithm simulated different potential gaits to create a shortlist of those that it deemed to be the fastest.

This, however, shed light on why insects have a tripod gait – and why it may not be the best option for robots. The simulations showed that the traditional tripod gait works in combination with the adhesive pad found on the ends of insects’ legs to make climbing over vertical surfaces such as rocks easier and quicker.

Robots, however, are typically designed to walk along flat surfaces, and so the benefits of such a gait are lost.

“Our findings support the idea that insects use a tripod gait to most effectively walk on surfaces in three dimensions, and because their legs have adhesive properties. This confirms a long-standing biological hypothesis,” said Ramdya. “Ground robots should therefore break free from only using the tripod gait”.

Study co-lead authors Robin Thandiackal (left) and Pavan Ramdya with the six-legged robot used in the research. Images courtesy of EPFL/Alain Herzog

To for always corroborate the simulation’s findings, the researchers built a six-legged robot that could move either with a bipod or tripod gait, and which quickly confirmed the research by being faster when moving with just two legs on the ground at once.

However, they went further by confirming that the adhesive pads were in fact playing a role in the insect’s tripod movement.

They did this by equipping the fruit flies with tiny polymer boots that would cover the adhesive pads, and so remove their role in the way the insects moved. The flies’ responses confirms their theory: they began moving with a bipod-like gate rather than their conventional tripod-style movement.

“This result shows that, unlike most robots, animals can adapt to find new ways of walking under new circumstances,” said study co-lead author Robin Thandiackal.

As bizarre as the research sounds, it provides valuable new insights both for roboticists and biologists, and could lead to a new standard in the way that six legged robots are designed to move.

“There is a natural dialogue between robotics and biology: Many robot designers are inspired by nature and biologists can use robots to better understand the behavior of animal species,” added Thandiackal. “We believe that our work represents an important contribution to the study of animal and robotic locomotion.”

Former US presidential candidate Ralph Nader warns against over-hyping driverless cars

Former presidential candidate Ralph Nader has said that unsubstantiated claims from driverless car enthusiasts are distracting authorities from improving transport links and improving road and rail infrastructure.

In a blog post, Nader argues that the while the many advantages of a possible driverless future have been reported by the media, they have not been properly scrutinised, and the technology is draining much-needed funds that should be made available to mass transit services and the industry’s own vehicle safety upgrades.

“The mass media took the bait and over-reported each company’s sensationalised press releases, announcing breakthroughs without disclosing the underlying data,” said Nader.

“The arrogance of the algorithms, among many other variables, bypassed simple daily realties such as bustling traffic in cities like New York.”

Image courtesy of Don LaVange

Nader makes the claim that the predicted decline in car sales has led car companies to promote their high-ticket, driverless cars, which as Nader points out are already being marketed as “computers on wheels”.

However, Nader argues no explanation has been given for how autonomous vehicles would be implanted into normal people’s daily lives, and the problems of cars being hacked or requiring humans to take over haven’t been resolved.

“The industry, from Silicon Valley to Detroit, argues safety. Robotic systems do not get drunk, fall asleep at the wheel or develop poor driving skills. But computers fail often; they are often susceptible to hacking, whether by the manufacturers, dealers or deadly actors,” said Nader.

“Already, Level Three—an autonomous vehicle needing emergency replacement by the surrogate human driver—is being viewed as unworkable by specialists at MIT and elsewhere. The human driver, lulled and preoccupied, can’t take back control in time.”

Nader also makes the point in his blog post that driverless cars are diverting funding away from making cars we already have safer, more efficient and less polluting.

It is Nader’s opinion that we shouldn’t wait for what he terms a “technological will-o’-the-wisp”, and we should instead make changes to the cars we already have, as well as improving public transportation and infrastructure.

“The driverless car is bursting forth without a legal, ethical and priorities framework. Already asking for public subsidies, companies can drain much-needed funds for available mass transit services and the industry’s own vehicle safety upgrades,” said Nader.

“Why won’t we concentrate on what can be improved and expanded to get safer, efficient, less polluting mobility?”

Self-driving shopping: Autonomous grocery delivery trialled in London

The first trials of a self-driving grocery delivery service have started in Greenwich, London, as part of a wider project looking into the use of autonomous vehicles for ‘last mile’ deliveries.

An initiative between UK government and industry funded smart mobility lab the GATEway project and Ocado Technology, a part of the world’s largest online-online supermarket, the trail uses a cargo-carrying self-driving vehicle known as CargoPod. Developed by Oxbotica, the vehicle can carry 128kg of groceries at a time, as is designed to drive in areas populated by pedestrians thanks to its software system Selenium.

“Last mile delivery is a growing challenge as our cities become denser and more congested,” said Graeme Smith, CEO of Oxbotica. “In this new project we are working closely with Ocado Technology to deploy our Selenium autonomy system into a novel last-mile delivery application in Greenwich as a part of the GATEway project.”

Running over ten days, the trail will see groceries delivered to over 100 residents across the Royal Riverside Arsenal development in the borough of Greenwich. The project is the latest in a series of trials of self-driving vehicles in the borough, which have been primarily focused on their operation in areas also used by pedestrians.

“The Royal Borough of Greenwich is one of the UK’s leaders in smart city innovation and we are proud to be working alongside our partners to be at the forefront in this new age of driverless technology,” Councillor Sizwe James, cabinet member for transport, economy and smart cities at the Royal Borough of Greenwich.

“With Digital Greenwich spearheading this work forwards, we are gaining new insights into how connected and autonomous vehicles, including automated light delivery vehicles, will impact on the city and what cities need to do to capture the opportunities they can bring.”

Images courtesy of the GATEway project

The eventual goal of the project is to bring self-driving vehicles into general use in the UK.

“The GATEway project takes us another step closer to seeing self-driving vehicles on UK roads, and has the potential to reduce congestion in urban areas while reducing emissions,” said UK Business Minister Claire Perry. “Backed by government, this project firmly establishes the UK as a global centre for developing self-driving innovation.”

As part of this, there has been a strong focus on the commercial opportunities of self-driving vehicles, as evidenced by the involvement of Ocado.

“Ocado Technology is delighted to have worked in partnership with the GATEway Project to a complete a very successful grocery delivery trial using driverless vehicles. We are always looking to come up with unique, innovative solutions to the real-world challenge of delivering groceries in densely-populated urban environments,” said David Sharp, Head of 10x Technology at Ocado.

“This project is part of the on-going journey to be at the edge of what is practical and offer our Ocado Smart Platform customers new and exciting solutions for last mile deliveries.”