PIAUÍ, June Issue, volume 93, 2014:

O Voo de Nicolelis, O Pioneirismo do Exoesqueleto Que Será Apresentado na Abertura da Abertura da Copa Está em Questão.

By Stefano Pupe

A Translation from Portuguese to English:

In 1906, Alberto Santos-Dumont was already a renowned inventor, having built some of the best airships of his era. But he, like many others, felt that the future lay in ‘heavier than air’ machines, able to fly without relying on hydrogen. And the highlight of his career was derived precisely from his famous prototype, the 14-bis, which incorporated many of the characteristics of what would later be known as airplanes. The flight of the 14-bis, performed as a spectacle in front of a large audience, temporarily established him in France, and permanently in Brazil, as the Father of Aviation. Santos-Dumont was a great visionary. But as is clear now, he was not the inventor of the airplane.

In the case of aviation, the definition of who developed the first ‘heavier than air’ was initially difficult due to the extreme secrecy with which the Wright brothers, Orville and Wilbur, conducted their experiments. The two were working as bicycle builders and mechanics, but their true passion was to build flying machines. They developed several models of gliders, and were dedicated especially to gain maximum control over their flights. To do so, they built tools like the wind tunnel, an advanced technology for the time, and a control system for lateral wing movement of their gliders that was an extremely innovative accomplishment. These tools allowed the Wrights to establish impressive feats when they applied this technology in motorized flight. In 1903, they were the first to achieve effective control of a motorized airplane, traveling a distance of about 40 meters. Constant improvements led them to reach, in 1905, a thousand times longer flights, almost 40 kilometers long. More importantly, they could fly in circles and control the direction of flight without difficulties, a feat equaled only many years later. Their machine, called the Wright Flyer I, was undoubtedly the most advanced so far.

It is difficult to say whether Santos-Dumont knew about the Wright brothers, but he certainly had no details about their inventions. Due to the secrecy that the Wright brothers maintained in relation to their plane, there was some mistrust in Europe that their deeds were exaggerated or did not exist. Therefore, in 1906, the International Federation of Aviation, located in France, still held open a reward for the person who could demonstrate that a ‘heavier than air’, motorized machine could fly. And that is what Santos-Dumont set out to achieve successfully with the 14-bis. The rules of this award contained a clause saying that the machine should also be able to take flight ‘on its own’. This is the point that still gives rise to numerous discussions, because the plane of the Wright brothers, for more advanced it was, usually depended on a kind of catapult to reach the necessary propulsion to fly. The 14-bis, which used a more powerful engine, was able to take off on its own, after some distance on land. Many argue that this clause gives priority to the Brazilian, who would be so entitled the Father of Aviation, since modern aircraft do not depend on a catapult. But a careful analysis leaves little credence to this position.

The first obstacle is that Santos-Dumont was also not the first to take off on his own. The Wright brothers did it on their first flights in 1903, before adopting the catapult. There are reports that at least three other aviation pioneers, Hiram Maxim, Karl Jatho, and Clément Ader were able to accomplish this feat and go over some tens of meters (the same distance traveled by the first 14-bis) several years before 1903. As with the 14-bis, the ability to control these aircrafts was extremely limited and their flights were little more than small hops. Furthermore, it is possible to imagine that modern airports could offer a ‘push’ to aircraft, if necessary—in fact, this is what happens on aircraft carriers, where the track size is limited—but it is difficult to imagine an airplane unable to set its own course. And on the topic of controllability, the prototypes of the Wright brothers were unbeatable. While the 14-bis ran 220 meters into a straight line in its longer flight (in 21 seconds), the prototype of the Wrights had already conducted flight by tens of kilometers across. Contrary to what one thinks of the Brazilian aviator, their flights were properly documented and attended by dozens of independent witnesses and researchers such as Ian MacKersey and Richard Halion, as described.

Tragically, Santos-Dumont did not know that when he flew in 1906 the glory and fame that followed lasted little in Europe, and in his final years he demonstrated sorrow at the speed with which he was forgotten. But perhaps the most important role played by Santos-Dumont has been as a disseminator of aviation. His flight with the 14-bis, coupled with his previous fame with his airships, put aviation on the covers of newspapers around the world, and proved that a fixed-wing aircraft, heavier than air could fly. French airmen such as Louis Bleriot, the first man to cross the English Channel in an airplane in 1909 and one of the most influential inventors of the early period of aviation was present on the day he flew the 14-bis. In short, Santos-Dumont was one of the first inventors involved with aviation, and certainly the most prominent. But assigning to him the role of the Father of Aviation is historically incorrect.

The current relevance of this historical discussion is by the direct comparison of Santos-Dumont with the contemporary Brazilian neuroscientist, Miguel Nicolelis, who has an energetic patriotism. And his idol gives its name to its largest enterprises. The non-governmental organization of Nicolelis is called the Alberto Santos Dumont Association for Research Support, and the exoskeleton he intends to inaugurate on the opening of the World Cup has the name BRA—Santos Dumont I. In a way, the trajectories of Nicolelis and Dumont are comparable. Both were born into wealthy families. Dumont was heir to one of the largest coffee farms in Brazil, at the time when coffee was the main commodity of the country. Nicolelis is the son of Giselda Laporta Nicolelis, celebrated author of children's books, and the son of a judge. Both Nicolelis and Santos-Dumont emigrated from the country relatively early in their careers, and they developed their professional lives outside of Brazil. And both have a taste for fame and challenges.

The current big ambition of Nicolelis is to make a paralytic Brazilian perform the opening kick of the World Cup 2014. Therefore, the strategy he will adopt is to build an exoskeleton, a kind of armor that envelops the lower limbs of the patient. This exoskeleton must be able to support the patient and move his legs on a walk, and eventually on a kick. Nicolelis believes that this project is the Brazilian moonshot, comparable to the arrival of the man on the moon. But like his idol, he may find some flags now stuck there when he finishes the trip. Various exoskeletons are being developed by dozens of independent groups worldwide. Some are in advanced stage: one paraplegic British patient was able to complete a full marathon (of 42 km) using the exoskeleton of an Israeli company (ReWalk), though it took several days. There are at least eleven groups that already have a prototype tested in humans with results published in international journals, and four of these are already commercially available. The challenge therefore is to develop the best exoskeleton—not the first.

The most audacious trump card Nicolelis has to achieve this comes from the attempt to control the exoskeleton via the brain of the patient. In a sense, any movement made by a person is derived directly from his or her nervous system activity, but what Nicolelis really wants is the ability to capture the signature produced by the brain activity, and turn that into an input to their exoskeleton. Brain cells, called neurons, have a form of communication that causes a small change in their electrical potential when they are activated, a change that can be measured in volts. Although the voltage produced by each cell individually is microscopic, the billions of cells of the human brain produce such a voltage together such that a potential can be measured with sensors placed on the outside of the head. The German, Hans Berger, was the first to discover this phenomenon in 1921, and today it is called electroencephalography (EEG).

Nicolelis has always defended another technique, the simultaneous recording of neurons through brain implants, as being more efficient than the EEG. So, his option for using the EEG for his exoskeleton caused some surprise. Although Nicolelis is limited to say that he considers it enough for lower limb prostheses, the explanation probably lies on the limited time that he has to make the demonstration at the World Cup, and the difficulties (ethical and practical) which have to be faced if the option were to use a more invasive method that he developed throughout his career. The French scientist, Guy Cheron, too developed an exoskeleton powered by EEG and sensory feedback called Mindwalker, whose ability he has shown in published articles. "With minor adaptations," he says, "[our] exoskeleton would also be able to take a few steps and kick a ball." This is also the opinion of Jose Luis Contreras-Vidal of the University of Houston. His exoskeleton, called NeuroRex, is powered by EEG and was tested on a patient with paraplegia. The results were published this year in a specialized journal. Contreras-Vidal says, confidently, that his NeuroRex would also be able to do the demonstration and he "would be willing to show it in the World Cup, along with Nicolelis’ prototype."

Originality is not the only problem. Although the concept of a paraplegic patient moving his legs again with his thinking is worthy of science fiction movies, from a practical standpoint the reality is not that spectacular. In clinical studies on humans, it is clear that the EEG distinguishes reliably between just 2 or 3 different commands. The precise movement of the legs requires a lot more complexity than those few command signals, and so what you can do nowadays is to leave most of the movement in charge by the exoskeleton, and leave to the user only rudimentary control with the brain. As Nicolelis has admitted, the type of command to the exoskeleton will be simple, something like ‘forward’, ‘kick’, and ‘stop’, and the machine will see that the details of this movement, as the balance and speed, will be established independently of the brain. And with the range of commands so limited, it is unclear how the exoskeleton will be able to make small adjustments, necessary for any movement. Andrew Schwartz (who unlike Nicolelis) has published articles reporting on experiments with artificial limbs in humans; he has stated emphatically in an interview with MIT Technology Review magazine: 'what would happen if a gust of wind moved the ball three centimeters to the right seconds before the beginning of the demonstration? All you will see is a demonstration of robotics, not brain control, and everything will probably be pre-programmed.'"

There is nothing wrong in performing experiments, and even an imperfect implementation may be needed for more to come later. The problem is that, by opting for a demonstration at the opening of the World Cup (well before publishing any article or relevant technical explanation of his project), Nicolelis stands above his peers and outside the scientific process to get into a media universe. And this is a universe in which clinical expectations are easily built, but expectations that are also easily disappointed later. Given the current state of the field of bran-machine interfaces, the clinical promise of the exoskeleton is dangerously exaggerated. The exoskeleton of Nicolelis is an analogy to the 14-bis by focusing on a more public display than on its practical applicability and on the degree of controllability provided to the user. Perhaps, as with Santos-Dumont, the reputation of Miguel Nicolelis in Brazil will stay sealed forever as the ‘Father of the Exoskeleton.’ It may be that it will work as the 14-bis, to give impetus to more funding and support for research in this area, due to the high visibility of the opening of the World Cup. But, unlike his idol who had good reason to believe that he was a pioneer, Nicolelis departs knowing that others are publicly ahead of him in this race.