Dismantling, loading, transporting, unloading and reassembling shelf [bimanual, activity] {illustration, a peek into the life of a person with a handicap}

This is a post to give you news about things in the life of a person with a handicap (i.e., me). If you are researcher or with a modern prosthetic component company, you would never have thought that (in all likelihood) we, your clients, actually haul ass. But then, if one is to inspect your prosthetic component catalogs or research programs, then one will come also to the conclusion that you primarily lean towards Thorsten Veblen.

And so I will allow you to peek behind the curtain of well hidden activities!

This, her, is about a shelf. A cheap Ikea shelf, with many parts and screws, boards and little metal pieces to hold it all together.

In the approximate temporal sequence, the shelf was

  • emptied
  • disassembled
  • parts carried across building and parking
  • loaded into car (all fitted neatly into my admittedly large station wagon)
  • transported with car
  • unloaded from car
  • parts carried to new room in new building
  • assembled
  • filled with items

I know that you are not building prosthetic parts to assist in such activities. Because nobody really is! With a few notable exceptions, this type of activity is totally unheard of! Even though I do have the feeling a few other people do a lot harder stuff with their prosthetic arms they are likely not going to post about it anywhere.

This is to supplement earlier posts about more extensive prosthetic loads such as here [link].

Shelf  parts loaded:


Nothing wiggled or slid there. No part dared. I had stacked these parts there for loading the car all by myself. How to load wooden parts for safe car transport also with an upper extremity difference, that may be a subject at one point. But I digress.

Shelf parts stacked up in hallway:

WP_20140608_20_47_08_Pro WP_20140608_20_47_20_Pro

Finished shelf with reassembled parts:


Most people doing research in academic jobs with the subject of prosthetic arms or hands will ignore realities such as the ones I continously write about. Instead they write something like the following type of texts (arbitrarily selected research papers from Google Scholar, last few months):

  • "Myoelectric control of prosthetic upper limbs is an established technology. While cosmetic features, weight savings, battery life, and components have significantly improved over time, the fundamental control strategies in the clinical setting have not changed. Amputees still control prostheses by using one muscle group to open the hand, and another to close the hand, with some advanced devices allowing movements at the wrist or specific grip patterns. The early strategies of on/off and proportional control have been shown over a number of decades to perform well, with consistent reliability. However, this is far from the capability of the natural human hand, which can frustrate prosthetic users, especially in an era of relentless technological innovations."
    [1] -- This works entirely omits the aspects of higher weights and object volumes, rather than similarly omitted single occurrences, of repetitive bimanual lifts, shifts and, basically, hard manual work.
  • Cipriani et al. [2] propose that "The restoration, following amputation, of dexterous control equivalent to that of the human hand is one of the major goals in applied neuroscience and bioengineering [1]-[5]." Is that now a major goal in applied neuroscience and bioengineering? In his stated research premises, Cipriani so elegantly ignores hard bi-manual tasks that amputees need to perform, that by the sheer size of that particular error or mistake, he simply must be overlooking other important aspects as well! Because, you see, amputees working hard manually is a real fact, and prosthetic arms under-performing is another real fact. Do you understand how my type of reasoning works? It is not just "neuroscience and bioengineering" as Cipriania wants to make us believe - no. His cited source [1] required a neurosurgeon to do the real work - first author of that paper actually! - to actually dig up some stumps of six human amputees and rewire them somehow. Cited source [2] also was written by an orthopedic surgeon supported by authors of a range of fields, including neurology, so surgery once more is forgotten to be mentioned; totally important though, as here as well, electrodes were invasively placed into stump nerves. Cited source [3] totally ignores the mention of author list contained surgeons and neurologists as well, with this being another invasive research. Source [4] references Todd Kuiken, a surgeon himself, who is known to not just implant tiny electrodes but majorly surgically rearrange and rewire amputee's stump and chest regions, so we are looking at major rehabilitative surgery here. Only [5] exclusively deals with bioengineering. In other words, Cipriani totally downplays the fact that he bases on stumps being routinely cut up surgically for the exclusive benefit of his research installations. Dextrous control equivalent restoration after amputation is also, if not first and foremost, a surgical aim and goal [cf. Krukenberg; Sauerbruch; Kuiken].
  • Aziziaghdam and Samur [3] opine that "Somatic senses (sense of touch, proprioception, pain and temperature) are lost after an amputation". Really, it is not that my hand and wrist remain while only somatic senses are lost. Along a similar argumentation, no one would say that "vascular systems (arteries, veins) are lost after an amputation". Much rather, with my hand, wrist and forearm, all things with it - skin, bone, hair, nerves, vessels - were taken (not lost, taken). My remaining arm, the stump, contains as much sensory function as a forearm has. So not more was lost. Worse, my prosthetic arm - a body powered tight ultra light ultra hard performance rig - conveys as much feedback to the stump as much as that stump usually handles well. The total amount of sensory feedback that my stump can discriminate well, given the low density of nerve endings on my stump compared to the density on my original hand, really is not all that much. But somatic senses, as such, are not lost. With an apparent further lack of logic, the writers continue saying that "sense of touch plays an important role in understanding physical properties of objects in contact and also let us accurately manipulate these objects". No! Sense 0f touch never manipulated anything. It is motor precision and - if objects are heavy - loads of power and grip mechanics, all properties along the motor output axis, that are aspects of a prosthetic hand that "lets us accurately manipulate" objects. I do not need one single force feedback to accurately move objects. To play integrated loop circuit, yes, to play force feedback eyes closed games, yes., for that I would need some feedback, be it by touch, or other senses such as vision or sound. But to precisely control just as such...? For that, I mainly and primarily need a lot of power and control over that power, to a degree that allows for actually precise movement while under significant load.

Makes you wonder what world these people actually live in themselves. Roboticists themselves, generally, do not appear to be totally incapable of actual honesty, of acknowledging the real issues and their failure when facing these.

Read this rare beauty that exposes relevant aspects of robotics [4]:

"Machines cannot feel and express empathy. However, it is possible to build robots that appear to show empathy."

So, it must be possible to get roboticists that are lost within the amputee and prosthetic arm subject to say this sentence, that I project:

"Prosthetic arms just cannot feel and express gestures just as a human arm does. However, it is possible to build prosthetic arms that can manipulate with precision, and that can help lift heavy items" (projected quote, by a still to be found but so far unknown roboticist) {Wolf Schweitzer, 2014}.

And for these so far mostly unknown but hoped to be there researchers, what a revelation really, this here must come as the total and utter surprise to these people! I am always glad to help them out with what must be for them: totally, new, insights. And hope! Possible acceptance by a wider community of prosthetic arm users!

The main parts of my prosthetic arm that are put under strain here are these:

  • Cable control - I will use a maximum amount of rubbers on the hook so as to make it grip as hard as possible, which will put a lot of strain on the cable control setup, so: note to researchers: build better cable housings that allow for friction fee grips of up to 50kg;
  • Socket - carrying and manipulating these items does abrade and bang the socket from its outside; so: note to researchers: sockets need to be both soft and bang resistant!;
  • Socket fit - carrying and manipulating these items requires the arm to well handle a lot of pulling force, hence, a perfect socket fit is one of the requirements, free and unrestricted elbow movement another; note to researchers: never dodge the suspension subject, ever; make it your top priority, always;
  • Wrist unit - no wiggle or coming apart allowed, ever; note to researchers: consider that one done [link];
  • Handling tools with prosthetic limb - obviously many screws, and accordingly, drills, wrenchs, screws, little metal bits and pieces are also all part of what is to be managed and installed here; note to researchers: keep it simple, since a simple gripper can be more lightweight and that, if you go ballistic with a prosthetic arm, for a whole day or so, is what ultimately spells out as overuse and pain;
  • Gripper - I use a Hosmer aluminum hook, but you may use whatever you see fit - even though I do wonder how a glove of an iLimb Ultra Revolution would look like, after 5 minutes, 10 minutes, 30 minutes, 2 hours and 4 hours of working in context of this (it took a total of around 5 hours to get it all done), and also, how the process would have gone, and, how your stump would look like. Note to researchers: build hooks that can be equipped with up to 50 kg grip force

I mean, really. Any halfways tech savy geek kid like me will want to go towards mechanical ultra high tech, rather than the overmarketed hype Dead Horse tech, that is inflicted by current "bionic" phantasies that really do not play out at all. Just saying.

[1] A. D. Roche, H. Rehbaum, D. Farina, and O. C. Aszmann, "Prosthetic Myoelectric Control Strategies: A Clinical Perspective," Current Surgery Reports, vol. 2, iss. 3, pp. 1-11, 2014.
  title={Prosthetic Myoelectric Control Strategies: A Clinical Perspective},
  author={Roche, Aidan D and Rehbaum, Hubertus and Farina, Dario and Aszmann, Oskar C},
  journal={Current Surgery Reports},
[2] C. Cipriani, J. Segil, J. Birdwell, and R. Weir, "Dexterous control of a prosthetic hand using fine-wire intramuscular electrodes in targeted extrinsic muscles.," IEEE transactions on neural systems and rehabilitation engineering: a publication of the IEEE Engineering in Medicine and Biology Society, 2014.
  title={Dexterous control of a prosthetic hand using fine-wire intramuscular electrodes in targeted extrinsic muscles.},
  author={Cipriani, Christian and Segil, J and Birdwell, J and Weir, R},
  journal={IEEE transactions on neural systems and rehabilitation engineering: a publication of the IEEE Engineering in Medicine and Biology Society},
[3] M. Aziziaghdam and E. Samur, "Providing contact sensory feedback for upper limb robotic prosthesis," in Haptics Symposium (HAPTICS), 2014 IEEE, 2014, pp. 575-579.
  title={Providing contact sensory feedback for upper limb robotic prosthesis},
  author={Aziziaghdam, Mohammad and Samur, Evren},
  booktitle={Haptics Symposium (HAPTICS), 2014 IEEE},
[4] A. Tapus and M. J. Mataric, "Emulating Empathy in Socially Assistive Robotics.," in AAAI Spring Symposium: Multidisciplinary Collaboration for Socially Assistive Robotics, 2007, pp. 93-96.
  title={Emulating Empathy in Socially Assistive Robotics.},
  author={Tapus, Adriana and Mataric, Maja J},
  booktitle={AAAI Spring Symposium: Multidisciplinary Collaboration for Socially Assistive Robotics},

Cite this article:
Wolf Schweitzer: Technical Below Elbow Amputee Issues - Dismantling, loading, transporting, unloading and reassembling shelf [bimanual, activity] {illustration, a peek into the life of a person with a handicap}; published June 11, 2014, 18:30; URL: https://www.swisswuff.ch/tech/?p=3216.

BibTeX: @MISC{schweitzer_wolf_1582724786, author = {Wolf Schweitzer}, title = {{Technical Below Elbow Amputee Issues - Dismantling, loading, transporting, unloading and reassembling shelf [bimanual, activity] {illustration, a peek into the life of a person with a handicap}}}, month = {June},year = {2014}, url = {https://www.swisswuff.ch/tech/?p=3216}}