to electrical signals from the brain to the muscles to activate the motors italian retiree marco zambelli has been testing the harness hand for the last three years he lost his hand in a work accident as a teenager and has used a variety of perspectives over the years the hardest and allow zambelli to complete tasks that would be unthinkable with most prosthetics regarding the driving for example is no problem but there are other day to day challenges like using a knife what i used to eat with others and they were all using knives i just did without but now i've started using them and i'm quite good at it. the hand was developed by the italian institute of technology and the state workers' compensation prosthetic center it has just one motor to operate all the fingers so it weighs only about as much as a human hand the developers say the simplicity also kept the cost relatively light around five million euros over three and a half years they say the low development cost means they can bring hummus to the market for around thirty percent less than similar press that ticks they hope to be s