PUMA’s digitigrade soccer cyborgsWednesday, 20 February, 2008
PUMA Football has a new advertising campaign showing soccer players that resemble cyborg satyrs or fauns (but with sleek metal replacing dark goat hair on the legs). PUMA sets the advert in the year 2178, which may be a very conservative estimate as far as the technology goes. But it may be a realistic date for the time when FIFA finally allows the rules on performance enhancing modifications to be relaxed in international competition (because, realistically, who wants to watch a traditional football game when the cyborg teenagers at the local park play a faster and more interesting game).
But, considering how distant this sort of development is, there isn’t much to talk about in terms of rules and regulation in sports on prosthetics, because currently a prosthetic limb is a hindrance in most sports.
So, instead, I will talk about the tech of these bionic legs, called the v1.178 Speed Legs. That is an accurate name, because as far as bipedal life goes, one of the fastest is the ostrich (the fastest, I think, is the kangaroo, but it doesn’t run with alternating legs, so I am ignoring it). The ostrich can run at speeds of up to 65km/h, in comparison to the current human record of 37km/h by Michael Johnson.
Humans have a plantigrade gait, meaning that we touch the ground with our full sole of the foot (the plantar surface)- from the heels to our toes. Birds, like the speedy ostrich, are digitigrade, so touch the ground only with their toes – the digits of their feet. The v1.178 Speed Legs are built in a way similar to the ostrich (with the toes lengthened just enough to fit into a typical 21st century PUMA sneaker). This should give a great advantage in running speed to any player who has them. Hence, the name ‘Speed Legs’ would be very accurate.
The power of the kicks may be a concern: much of the power of the kick comes from the extension of the knee with the quadriceps femoris muscles, but a significant amount comes too from the swinging flexion of the thigh at the hip. These bionic limbs do not appear to mechanically interface with the body in any way, as they simply replace the pelvis and limbs that attach to it (what this does to sexual function, I can only guess). Therefore, one of the greatest hip flexors, the psoas major muscle, which runs from the lumbar region of the vertebral column to lesser trochanter of the femur. With a complete amputation and replacement at the pelvic level, this muscle’s action would be absent, leaving only the weaker illiacus and other adductors of the inner thigh that can also act in hip flexion. Perhaps the free swinging causes by movement of the knee in combination with the bionic equivalents of these other hip flexors will be enough to form a powerful kick, but I would have thought by 2178 that the interface between bionic limbs and the human body would encompass a smooth musculoskeletal interface, allowing for optimum function.
But, perhaps I am being overly critical of something that was probably not designed by a biomechanical engineer. So, I’ll just shut up and watch the ad again.