Even though I'm still in the calibration troubleshooting stage, I wanted to start this thread to ask the Chordata Team about suit materials, and for myself and others to post about materials they have used that have worked well.

Right now I'm wondering about the foam used in current versions of the suit. Should be we using a certain kind of foam? I know some foams have a tendency to build up static electricity, so I want to make sure I'm buying something that won't break my sensors.

Also, while I know the 3D printed K-Ceptor socket didn't work out, have you tried small plastic project boxes at all? Or perhaps project boxes in combination with screws and foam?

If not, I'd be willing to try that out. I finally found an electronic components retail store in my area that has some reasonably priced boxes.

As for the straps, I'm not sure what I'm going to do about that yet, but I'm currently looking into velcro cable ties and smart phone arm bands for jogging.

We didn't have any problems with static electricity coming from the foam on the KCs. The real problem with static electricity comes when the performer has to move over a carpet.

You're right to be worried about this. One little static discharge might blow exposed electronic components. So using little boxes might be a good idea.
That said, we used the suit on several occasions (and for several hours) over a carpet and we never got a blown sensor.

I updated the wiki with photos and comments about the current velcro solution we are using. Still not really happy with it, but that's what we have for the moment.
https://wiki.chordata.cc/wiki/User_Manual/1.Chordata_parts/1.3.Sensor_Fixings#New_version_of_velco-based_fixing

And I also uploaded the 3D printable plastic socket in case you want to take a look, or perhaps use it as a base for further development.

25 days later

So I did some window shopping yesterday and I think between some athletic gear, a modular small photography bag, and ordering some velcro straps online, I'll be able to put together the suit. However, I'm unclear on how the base K-Ceptor is secured on the suit.

From the videos I've seen, it looks like the Hub is usually mounted on the bottom of a back brace and the base K-Ceptor is positioned on the sacrum, but how is it held in place? Does it just hang down from the back brace? It seems like doing that would result in some unwanted sensor movement. Did you attach an additional strap that runs through the legs so it attaches to the front and back of the brace, thus providing a stable strip of fabric where you could mount the K-Ceptor?

    AxonSpark base K-Ceptor is positioned on the sacrum, but how is it held in place?

    For situations when the performer is not doing any abrupt movements we use a belt with a piece of velcro stitched to it.

    When we are capturing something more dynamic like dance, it is a good idea to stitch the velcro to a body, elastic pants or other tight clothing.

      13 days later

      Just dropping a note here for other testers: all brass screws are working as a non-ferrous solution for securing the K-Ceptors. I've gathered most of the suit materials (currently waiting on a shipment of project boxes), and will do a video on my build once I have everything.

      I've been experimenting with a 3D printable k-ceptor case. Nearly have the top working. For the bottom I was thinking of creating a press-stud like system for easy removal of units without having to take the straps off a performer. I work with high school students so toughness is needed. I foresee a future with a conventional suit where a student stands on a kceptor. This way the straps/suit goes on then these click into place. When I get a good fit, I'll put up an stl. Thinking of a click system to do away with screws entirely and a nice cut out of the logo lit up by the internal blue LED when connected
      My first design had the connector ports open but I think a little plastic over them will help with durability. I also think an arrow cutout is important to show which way the units sit. Students had a tendency to wire it up wrong putting ins into outs and outs into ins. Maybe the production suit could have different in/out connectors so that couldn't happen?

        tommasters I foresee a future with a conventional suit where a student stands on a kceptor. This way the straps/suit goes on then these click into place. When I get a good fit, I'll put up an stl.

        That would be a great contribution! Admittedly the current support (or even advice) in terms of the physical fixings leaves much to be desired

        tommasters Students had a tendency to wire it up wrong putting ins into outs and outs into ins

        Everyone does 😅
        The connectors should be changed on future revisions, thanks for pointing that out on the dedicated thread

            tommasters Something else you might want to do is make some shallow extrusions into the 3D model to emboss the numbering and lettering of the calibration box on the sides of the case, so you don't have to remove the K-Ceptor if you need to re-calibrate.

              7 days later
              3 months later

              Hey Developers & Testers!

              So I realized I never really posted on my approach to putting the suit together, so here are some notes on what I did.

              K-Ceptors

              For the enclosure, I used this project box. If you want to get it from another vendor, this is a Hammond Manufacturing translucent blue plastic enclosure, Item#: 1593KTBU. This box fits the K-Ceptors perfectly, and if you want you can remove the sides covering the input/output. I opted to cut holes in each side instead, so I could put the calibration markings on all sides so I don't have to remove the K-Ceptor when I calibrate it. To keep the K-Ceptor securely mounted, but also avoid possible interference from ferrous metals, I've used all brass screws. The case is held together by 2 - 4-40 3/4 inch flat top screws with pointed tips.


              Inside, the K-Ceptor is mounted using 4 - 4-40 3/8 inch screws and 4 - 4-40 hex nuts.



              Also, to keep the K-Ceptors more or less level, I used 2 - #6 nylon flat washers.


              To prevent the hex nuts from coming loose, I used a sanding bit on a dremel to make 4 depressions in the foam (this was cut from 9x12 inch, 6mm thick foam sheet from Jo-Ann Frabrics under the Little Makers brand), and added hot glue to the depressions and the surface to affix the bottom part of the K-Ceptor box. Then I added velcro with adhesive backing the foam in order to attach them to the straps.

              The Hub & Raspberry Pi

              These parts have been a little problematic, in that I can't find a project box that fits both of them, but also fits into the belt pouch I purchased (Really, I just need Hub box to be just a little higher, but I haven't found such a box yet. So for now I just stack them like this when I put them in the pouch:

              To mount the Hub to the box, I used 4 - 1-72 1/4-inch screws each with 1-72 hex nut, as you can see here:

              I might have a bit more to post on this later, but for now it's time to put together the new spine test rig and figure out what I'm doing wrong.

                Hello AxonSpark ! I'm Flavia, the manager of Chordata's social networks. I love what you have done with the hardware, thanks for sharing this! We'll make a post of it in our social media (meanly in Instagram, Facebook, and Twitter) in the next few days, so keep an eye on it! Also, if you have a public profile in these networks, let me know that so I can tag you 😀

                  6 days later

                  Hello AxonSpark ! Thanks for your quick response! I'll post your photos today on Instagram, Facebook, and Twitter, and tag you 😉.
                  No worries for grammatical errors, your post it's clear enough!

                    2 months later
                    5 days later

                    Hey @highmatergogo,

                    How are your elastic bands working out in terms of slippage? I'm hoping to replace the stiff velcro straps I'm currently using with either that or something like this, which seems to be similar to what Perception Neuron uses:

                    Also, while doing my tests today I realized that the GoPro headband I'm using has the sort of material that I'm looking for:

                    The question is, what is this? Googling 'elastic band with rubber grip' doesn't bring this up. Alternately, I'm wondering if it might be possible to buy a bottle of whatever is used to make these rubber grips. It looks glue gun-like, but that sort of glue doesn't really grip, and would definitely break when stretched where as this does not. Any ideas on what this might be? Pretty sure it's not Plasti-Dip.

                      AxonSpark they're holding up really well actually.

                      The only issue we have with slippage is the thigh as this is two elastic bands joined together. It's quite slack and thus, slips.

                      I like the look of those velcro straps with the loop but you'd be reliant on pulling it tight in order to keep it in place which may be come uncomfortable. Elastic is great as it keep constant, even tension around the limb but not so much that it is uncomfortable.

                      I've found some "elastic with silicone grip":

                      Obviously that's UK Amazon but I'm sure you'll be able to find similar using similar keywords.

                      Hope it helps!

                          Yeah, that material is definitely silicone on the backing. There appear to be both "dots" and "waves" varieties. I'm wondering if it isn't just better to put the dots/waves onto a mounting for the k-ceptor itself rather than worry too much about the straps. Obviously having the straps secure is a plus, so using this wouldn't be an issue, but I'm wondering if it isn't sensible to add some jaggies to the undersurface of a housing (so 3D print a k-ceptor housing that has ridges on the underneath where it would contact the body), give the housing a bit of grip in the same way these dots/waves do for the elastic.