Log Wearable PC

[BikingViking11]

As a streamer of bicycle mechanics, carpentry and computer projects I have been on a long mission to implement a Point Of View camera to show what my hands are doing. After trying phones (limited in quality and by apps only), a Raspberry Pi (limited by my lack of Linux knowledge) or expensive hardware HDMI wireless links I decided to just go with a Win 10 PC.

After coming across the Chuwi Larkbox Pro (albeit a bit late) I knew I'd found a solution.

The real challenge seemed to be getting it to run from a battery. Although it uses a USB-C port for power it is merely "USB-C-like" and requires 12V/2A for power. I was led to believe that a Power Delivery battery bank, specifically one by Novoo would power it due to a Twitter picture with no actual backing info...just a picture.


In a word, it didn't work. As @AlexTSG said, there's no room for the PD chipset and why would there be? PD is designed for quick-charging batteries and the Larkbox has none.

After looking into DC to USB-C cables whose reviews all said that they did not work for providing 12V power, considering the daunting task of figuring out the pinouts on a USB-C plug to make my own cable (and potentially letting the smoke out if I failed) I took the easy way out and bought a battery bank with an AC plug so I can just use the stock power adapter.

This was not without issues. The Ravpower battery bank, nearly the smallest I could find with an AC plug has a power-saving feature that shuts off the circuit after 60 seconds if it doesn't sense a load. Yep, the Larkbox is so efficient that it didn't meet whatever threshhold was built in to the bank and it shut off! One of my viewers dug into the FAQs like a fiend and found out that as long as the USB port is also charging something, the AC plug stays on. Considering that I will be using that USB to power a small AMOLED screen anyway, it became a non-issue. Once I receive the rest of the parts I'll be doing a test stream to see how long it will run on the battery.

The wearable aspect depends on a yoke I'm designing as I go. The basic concept came from a sculpter streamer that uses a harmonica yoke to hold a webcam that shows what his hands are doing. My yoke needs to be completely wireless as I move around too much to be tethered. It needs to hold the battery bank, the webcam, a small screen to check the camera view and monitor chat and the webcam itself. I took some copper electrical wire and started bending and soldering.

And then started reinforcing it with ladder bracing.

Then narrowed it down a bit for more comfort.

And added tabs for embedding the T-nuts that will allow all the components to be mounted.

I bent a battery bracket out of acrylic plastic sheet that will cradle it nicely on the back of the harness and be held in place with a velcro strap. The whole framework will be wrapped in casting tape, the same water-activated tape used for casting broken bones which should stiffen everything up nicely, yet still allow a little flex for movement. At a ballpark estimate the entire assembly should weigh less than 5 lbs.

I will be using NDI to stream the content to my main computer over the network. This requires a CPU with an SSSE3 instruction set, something the Pi's ARM processor lacks. I did a direct test stream with the Larkbox and despite the robot voice (new mic is also on the way) I was quite pleased.

twitch]video_id=791498389

It will take a while to get here as it's being shipped from Lithuania, but the camera will be a streamer staple: the Logitech C920...with some modifications.

Kurokesu has a lot of interesting cameras and modifications and one for the C920 that allows for interchanging lenses with a CS mount. The lenses are cheap, come in a wide variety and are small enough to not be intrusive or weigh a ton. I should be able to get whatever view I desire or even change it for other purposes than showing what my hands are doing, such as bicycle rides, covering events, etc. Tethered to my phone I'll be able to stream anywhere there's coverage and with a lot more flexibility than with just a phone.

Right now I'm just trying to get all the tabs and connections needed on the framework before wrapping it. Updates coming soon after more hardware and progress arrives. Thanks for reading.

 

[Solo]

That grimy ass keyboard and selfie are two things I didn't need to see first thing this morning. Sick project though.

 

[BikingViking11]

That grimy ass keyboard and selfie are two things I didn't need to see first thing this morning. Sick project though.

Hah! Yeah, just a beater keyboard that lives in my garage. As for the selfie, I blame no shave November and just showing how it will be worn. I'll crop my head off next time, I promise.

Sorted out a few quirks this last weekend and still waiting on a few parts including the display. On my stream a buddy had doubts about the casting tape since it's a one time deal. Forget something or decide later that it would work better in a different configuration and you'd have to cut it apart and start over. My plan now is to mount every component using 1/4-20 T-nuts that are standard for mounting cameras, mics and other audio/video equipment. I'll embed them all over the yoke so there's lots of choices in mounting configurations before the wrap seals them in. Stainless T-nuts, screw on cable anchors and a "magic arm" mount are on the way.

 

[BikingViking11]

After a few setbacks the project is back on track.

My first attempt at the casting tape was a fail. In an attempt to keep all the threaded inserts cleared I tried wrapping it around short sections of allthread screwed into every hole. This took more time cutting the tape with scissors to fit over them and by the end the tape was bonding to itself on the roll. I waited until the next day just to be sure and it easily peeled off. Back to the drawing board.

I covered the rest of the framework with Whitemorph thermoplastic and took some time with a heatgun to reshape it and smooth it out. While it does feel much more solid, it also gained some weight.

I decided to ignore all the inset threads and just wrapped it with the casting tape, once in one direction and another layer in the opposite direction. It went much more smoothly. It will be getting a coating of epoxy, wrapped with electrical tape to compress the fibers and then sanded and painted. Poor man's composite construction, but it works.

In the meantime I made up a little brass bracket for the Chuwi Larkbox that utilizes the studs that were provided with the VESA mount.

After cutting out the pieces and sanding them they were clamped in the vise with wood blocks, torched, soldered, sanded and polished making for an integrated bracket that can be mounted anywhere on the yoke.

After some tedious work cutting through the casting tape with a hobby knife at each insert location I was able to mock it up.

Oh, the fancy AMOLED screen? Well, it was either incompatible or defective. Couldn't get it to work correctly no matter what I tried. Heck, I even read the insructions! The display in the pictures is a "lesser" 5 inch screen and works just fine. I'll be returning the AMOLED and pocketing the $100 in price difference. Here's the test run.

Still to come: I'll be building a custom case for the new display that interfaces with the articulated camera mount. Yep, Od School made by hand. Believe me, if I could 3D print it I would. I was also notified that the camera rework kit will be arriving this week, so more updates are coming soon.

This has been a learning process, working with materials I'm not that familiar with and making something I've never made before. I've come up with several different approaches I could've taken, but I'll just finish it as initially concieved and save all that for uprades once it's up and running.

 

[BikingViking11]

As of today the Kurokesu camera kit is completed. Better yet...it works!

(Pictured using a 25mm lens for close shots)

The kit was fairly straightforward, though it did challenge my soldering skills. I'm no spring chicken at 54 and the eyesight isn't what it used to be. Fortunately I got past my pride enough to invest in some tools to help with that.

Implementing the kit breaks down to unsoldering the old hardwired USB connection in favor of an external connector, replacing the IR filter and removing the SMD LEDs so they don't interfere with the camera sensor. The SMDs were a real challenge since they're about .5mmx2mm and required two soldering irons to remove. They make a grain of rice seem huge. The instructional video shows this being performed with just one iron, but I'm sure that technique was learned after doing hundreds of conversions. The camera is available complete, but I went with the kit due to the long lead time, increased price and the fact that I already own several C920s.

From here it's just a process of refinement. I did make some progress on the case for the display, but it's been a struggle. Again, it's just tiny. When running a router on the lowest speed to mill out the back of the bezel it was still too fast and distorted the acrylic slightly. I can probably fix it (or even start over, it's just plastic), but that's just more work I was hoping to avoid. I always try to do work I'm proud of, so it's disappointing when plans don't work out. I'll keep working on it.

In testing I was having some issues with the battery pack staying on for AC power. It's nothing I want to deal with especially when the harness is worn because the battery is mounted at the back and inaccessible unless the yoke is removed. I've ordered another battery pack that is smaller, lighter and yet rated at a higher capacity (24000mAh versus 20000mAh) and has a manual switch for the AC outlet versus the digital controls, hoping that simpler is better.

Thanks for reading.

 

[BikingViking11]

OK, so I've been busy!

A lot of work has been done, I just haven't been posting it. As I said before the custom case was a bit of a struggle, but I pushed through and finished it.

After the casting tape went on I delayed doing the next step which was embedding it with epoxy. The temperature fluctuates too much in my shop to count on it curing out properly, so I went with coating it with Mod Podge and then spraying it with Plasti-Dip.

Before that I had to fabricate a new bracket for the new battery pack as the shape was completely different.

The new bracket was lined with neoprene for some grip and then velcro was embedded in it to keep it there. So far it seems to hold very firmly. After the Plasti-Dip I was able to assemble it all again for testing.

Testing shows...it works! I was able to stream directly from the yoke without sending it to my main streaming PC for upload. I can actually take this on the road for hands-free videography, ride a bike, whatever. The only thing that seemed to suffer was the configuration. The display was hard to see and the camera was a bit low for a true POV. Fortunately I had the forethought to make all the embedded 1/4-20 T-nuts interchangeable.

I was able to move the display over and down to make text more legible. It's still a tiny little screen and tough to navigate, but it does help with aiming and adjusting the camera. I will also be using it to monitor my chat while streaming. Here's what it looks like when worn and after adding a longer "magic arm" to raise the camera up for a better POV.

Other things to come: I tested it with a second camera and it works, but the cameras I have are too narrow a field of view to get a good shot so close to my face. I'll be ordering a mini fisheye cam for that.

Controlling the Larkbox and the stream isn't as easy as I'd hoped. The touchscreen function doesn't seem to work, but even if it did it's so small it's hard to see anyway. I'm planning to add an Elgato Stream Deck to it strapped to my wrist. This will give me hotkey buttons to control the stream, but as I found out, by using some software called Companion I can even control my main streaming computer as well through my network when I'm just using the POV as a source.

I will leave you with my test video. Thanks!

 

[ignsvn]

This is not my thing but dang it's impressive.

Small touch screen can be annoying especially if you need see small UI elements. Try to check onAliExpress, there are many portable monitors that supports touch functionality. There are quite a few for Raspberry, they may have the size you prefer.

 

[BikingViking11]

This is not my thing but dang it's impressive.

Small touch screen can be annoying especially if you need see small UI elements. Try to check onAliExpress, there are many portable monitors that supports touch functionality. There are quite a few for Raspberry, they may have the size you prefer.

I did try another 5" AMOLED monitor first and it didn't work. Even if it had I'm not sure it would work the way I'd want it to unless I had the option to use a larger screen. I had to balance between weight, size and convenience. The Stream Deck will probably be the best answer for the interface once I get all my macros set up so I won't be so dependent on the small visual screen space.

Thanks for the compliment as well as the comment that it's not your thing. It was built for a very specific purpose and I know everyone has a different usage scenario for their gear, I just thought by sharing it it may inspire other ideas for other needs.

I'm already changing a few things. I'm adding a sports camera with image stabilizations to get rid of some camera shake. Later I hope to improve upon that by using a Feiyu gimbal for that sweet mechanical stabilization that doesn't tax a CPU and cause delays. I'll also be adding a fisheye cam aimed back at my face.

One thing that came up quite often when I was researching the Chuwi Larkbox Pro was a general concensus in the reviews that it's a "Cool tiny computer, too bad it's too weak to actually have a purpose." For the power it consumes (10W) I've actually been impressed with what it can do especially from a power consumption/computing power perspective.

EDIT: I'd also like to add that I love the Asterix profile pic. A friend is working on one for me based upon the same art style.

 

[ignsvn]

If I remember correctly there are a few members of the forum that tried Chuwi Larkbox before, may want to search & see if it's beneficial for your project.

The (Elgato?) Stream Deck is fantastic. If you don't need the fancy icons then you may want to try custom mechanical keyboards:

Gherkin:

Iris or Lily (Some of these split keyboards need both sides, some can work with only either left or right side):

Macropads:

 

[BikingViking11]

The (Elgato?) Stream Deck is fantastic. If you don't need the fancy icons then you may want to try custom mechanical keyboards:

While I sort of like the fancy icons, the compelling reason to use the Stream Deck is for use with the Bitfocus Companion software. From what I understand, with some listening software on my main streaming PC I'll be able to control it through my network with the Stream Deck. I move around a lot and have avoided the SD so far due to no wireless options. Sure, there's a few other apps that will run on a wireless device, but I've been disappointed in all that I've tried so far. One thing you can say about the Stream Deck is it's very popular and there's also a lot of support out there for it. The software is also allegedly pretty versatile and compatible with most of the software streamers use. Since I do work during my streams the less distractions the better. Easy to visually acquire and logoed buttons sounds like just what I need.

I had a bit of a disappointment yesterday when I found out that my choice for the sports camera with image stabilization, the Akaso V50X doesn't have the same webcam functionality as the V50 Pro. It's a paltry $10 difference between them so I'll be sending that back and ordering the Pro. The webcam function both powers the cam and transfers data so it's not limited by the battery life...just the big one on the yoke.

The cheap fisheye camera however was pretty cool. Even 6" away my full face is in the shot. It has huge distortion with the 180 degree lens, but I kinda like it. I started making a case for it tonight since it's just a bare PCB camera.

I used white acrylic sheet and bent it around a block of wood cut to 32mmx32mm. A 1/4-20 T-nut will be embedded into it for a tripod mount and it will be finished off with some vinyl dye to fit in with the all black theme.

 

[BikingViking11]

Last night I got a bit further with the camera case.

The embedded T-nut came out a bit off center, but not bad considering I had to melt it into the plastic with a torch and soldering iron.

 

[BikingViking11]

After a bit of internal work adding some foam to protect the camera board and countersinking a couple screws to hold it together it got painted with vinyl dye.

I'll be making a custom cable when I get some time, but it's up and functional. After the sports cam and gimbal comes tomorrow I'll be doing some test streams while on the bike.