Reading reviews of people who try bionic arms (myoelectric prosthetic arms), they talk about following challenges: - High price - Good myoelectric arms can cost upwards of USD 50k to USD 100k and insurance doesn't cover it generally (so people are not able to afford it) - Precise movements are precontrolled - Like grabbing movement is triggered by a command sent from the muscle and not done like we do normally - This means custom, precise movements cannot be made (and perhaps researching that is the opportunity) - "Our hands are INCREDIBLE tools, one of the most advanced components in the animal kingdom. You might respond with a Shadowhand gif of someone holding an egg or something similar but those are mostly pre-formed poses AND that's based on conscientious movement. That says nothing about reaction time or true manipulability." - "There are typically only two “contact site” sensors inside the socket — this is called a “dual-site” system — so you need to cycle through a series of grip patterns by flexing twice in quick succession inside of the socket to get to the one you want." - Lack of feedback - https://www.youtube.com/watch?v=PLk8Pm_XBJE - Feedback requires some intervention at the time of the surgery - Unlike regular arms/hands, there is no feedback from bionic arms, so precisely controlling finger movements becomes difficult - Well, at this point, accuracy. For instance, grabbing a plastic cup, it's so easy to crush and spill your drink. Other sort of solid containers are perfectly fine. Granted I've only had it about a week now, but I do not foresee that getting any easier, mostly because there is no feedback. - " In fact, more amputees _prefer simple cable driven systems over the electronic prosthesis_." - it doesn't look as cool but the fact is you get near-instantaneous reactions because they are kinematically linked to your own body's motion - Desired: "the performance of a myoelectric without the assistance of sight." - But lack of feedback also helps the user be fearless - "Mostly because it doesn't hurt, so I don't have to brace myself or worry about hurting myself."" - Accuracy - Reasons for declined accuracy - the ability of the user to generate clear muscle signals at the sensor sites; - the unpredictability of the sensors’ ability to detect myoelectric signals, which is heavily affected by the quality of contact between the sensors and the skin; - the electromechanical delay in the bionic hand’s response to detected signals. - 'typical users may attempt 1,200 grasping motions a day with a bionic hand. If the accuracy rate of the myoelectric control system is only 80 %, i.e. an error rate of 20 %, this equates to hundreds of errors per day.' - Charge running out - "It usually lasts me all day, but if I use it a lot, it will be dead by noon and then I'm stuck with a dead hand all day" (that's bulky and inconvenient) - No anticipatory movement - Like we do with normal hands - Weight perhaps? - "it felt heavy as hell. It was only three pounds or so, but three pounds feels like a ton to a limb that typically carries no weight, and the heft of the prosthetic hand pulled hard on the socket and made me sweat." - Doesn't compete well with adapted behaviors without the limb - "Prosthetic arm technology is still so limited that I become _more disabled_ when I wear one." - Limit contact sensors with the body - Some [advocacy groups](https://bionicsforeveryone.com/bionic-hands-finding-the-right-myoelectric-control-system/#) have suggested that the high rates of dissatisfaction with bionic limbs are primarily the result of the inadequacy of “dual-site” myoelectric sensor systems - Lack of adequate personalization - "residual limbs are like fingerprints" **Cool things:** - No extra mental effort for operating it - "Otherwise, when it comes to articulating my fingers and working it in conjunction with the rest of my body, it's getting to be much easier, and almost happens without any concentration," - Being able to type! - "I can type with it, but not nearly as quickly as I've grown to typing without it." - Fast training (within 5 minutes) - I hit the ground running when I got this, about 5 minutes in to it I had almost complete control, - Watrerproof - In theory, better than natural limbs - "Paralympic legacy showed the world that amputees can run a 100 meters faster than most of us can" Stats - 40 million people need prosthetics and only 5% have them Sources: - https://www.reddit.com/r/IAmA/comments/14qoem/iama_bionic_man_ama_ilimb_prosthetic_arm/ - https://www.reddit.com/r/IAmA/comments/4y5jax/i_am_the_engineer_who_developed_the_worlds_most/ - https://www.inputmag.com/culture/cyborg-chic-bionic-prosthetic-arm-sucks - https://bionicsforeveryone.com/bionic-hands-finding-the-right-myoelectric-control-system/# - https://bionicsforeveryone.com/advanced-neural-interfaces-for-bionic-hands/ <iframe class="signup-iframe" src="https://invertedpassion.com/signup-collector" title="Signup collector"></iframe>