Posts Tagged ‘Donna Lu’

By Donna Lu

High-tech shoes are making running more efficient – eventually, they could help us run more than 50 per cent faster.

David Braun and Amanda Sutrisno at Vanderbilt University in the US, modelled the energy used during running and the factors that can affect that – including air resistance, the limited power of a human leg, and the losses that occur each time a foot hits the ground.

They found that the leg only supplies energy about 20 per cent of the time that a person’s foot is on the ground. To improve upon that, they have conceptualised a spring-powered device that would increase the amount of power a person’s legs generate while running.

An exoskeleton connected to each foot that contains a programmable spring would allow the leg to supply energy 96 per cent of that time, according to their analysis.

The device would store energy created as the leg bends in the air, compressing the spring, and release it when the runner takes a step. It would also lessen collisional energy loss. “I would compare this to a catapult that is pulled up in the air and then released on the ground,” says Bruan.

The stiffness of the spring in the envisioned device would need to be changeable. “The faster the running motion is, the stiffer the leg should be,” says Braun. The simplest way to do this would be to build in a way to change the active length of the spring, he says.

The researchers analysed the running style of 100-metre sprint world record holder Usain Bolt, who runs at a top speed of 12.3 metres per second. The device would in theory boost Bolt’s top speed to 20.9 metres per second.

Even if the device increased the proportion of time the legs are generating power to only 60 rather than 96 per cent, it would still enable a theoretical speed of 18 metres per second, says Braun.

The researchers are currently building a prototype. Braun says the device could eventually be used by the military, but also for recreational purposes. “People love things that allow them to move faster,” he says.

Journal reference: Science Advances, DOI: 10.1126/sciadv.aay1950

Read more: https://www.newscientist.com/article/2238609-spring-powered-shoes-could-help-us-run-more-than-50-per-cent-faster/#ixzz6HnsLNJ3H

By Donna Lu

An artificial intelligence has debated the dangers of AI – narrowly convincing audience members that the technology will do more good than harm.

Project Debater, a robot developed by IBM, spoke on both sides of the argument, with two human teammates for each side helping it out. Talking in a female American voice to a crowd at the University of Cambridge Union on Thursday evening, the AI gave each side’s opening statements, using arguments drawn from more than 1100 human submissions made ahead of time.

On the proposition side, arguing that AI will bring more harm than good, Project Debater’s opening remarks were darkly ironic. “AI can cause a lot of harm,” it said. “AI will not be able to make a decision that is the morally correct one, because morality is unique to humans.”

“AI companies still have too little expertise on how to properly assess datasets and filter out bias,” it added. “AI will take human bias and will fixate it for generations.”

The AI used an application known as “speech by crowd” to generate its arguments, analysing submissions people had sent in online. Project Debater then sorted these into key themes, as well as identifying redundancy – submissions making the same point using different words.

The AI argued coherently but had a few slip-ups. Sometimes it repeated itself – while talking about the ability of AI to perform mundane and repetitive tasks, for example – and it didn’t provide detailed examples to support its claims.

While debating on the opposition side, which was advocating for the overall benefits of AI, Project Debater argued that AI would create new jobs in certain sectors and “bring a lot more efficiency to the workplace”.

But then it made a point that was counter to its argument: “AI capabilities caring for patients or robots teaching schoolchildren – there is no longer a demand for humans in those fields either.”

The pro-AI side narrowly won, gaining 51.22 per cent of the audience vote.

Project Debater argued with humans for the first time last year, and in February this year lost in a one-on-one against champion debater Harish Natarajan, who also spoke at Cambridge as the third speaker for the team arguing in favour of AI.

IBM has plans to use the speech-by-crowd AI as a tool for collecting feedback from large numbers of people. For instance, it could be used by governments seeking public opinions about policies or by companies wanting input from employees, said IBM engineer Noam Slonim.

“This technology can help to establish an interesting and effective communication channel between the decision maker and the people that are going to be impacted by the decision,” he said.

Read more: https://www.newscientist.com/article/2224585-robot-debates-humans-about-the-dangers-of-artificial-intelligence/#ixzz66PTD9YuG