Steve’s Junk

Well, the past few weeks have been eventful and interesting. I’ve been busy and school is almost over. I’ve had a few things on the go and I’ve come up with some interesting ideas and implementations. Sorry for the lack of images in this post but I’ve been lazy taking them.

The DIY Measuring arm
This idea came from the need to build a measuring arm at a very low cost. I simply used some wood and some regular linear potentiometers.

This so far works reasonably, though it does have some linearity issues. I will need to bring this unit in to the shop to measure the joints and determine the exact positions in order to calculate the position.
Rock band device
I was inspired by a fellow classmate to build a device for teaching children how to play the drums and other instruments. I can’t get into any hot and heavy details, however it was a success for two drums to be made. The sensors worked and transmission of the data was reliable and the software worked. It was a lot of fun to build and we may work further on the idea with better design specifications.
Auditory Camera level
My idea for an auditory camera level is working to an extent but I’m having difficulty filtering out the vibrations from arm shake and the like.

Anyways, things are going well but it’s a lot of birds in the bush and none in the hand. I’m just writing to keep a log of what’s happening

Well, I’ve been at Microbusiness Training center for 5 weeks now and I’ve been working as well. Soon, Eight-M Technical Services will be operational and i’ll be working for myself.
I’ve set up a new domain with my Dreamhost account. The site’s URL is http://8mtech.com. As of posting this, the site isn’t ready, but it will be soon.
The viscometer is being tested by Endura right now and here’s what it looks like, it’s a youtube video, be warned.

also, I figure it’d be neat to post the logo for Eight-M technical.

my logo for 8m

Some people who have known me since Junior High would know this symbol. While it was something I used as a kid, I started using the name Eight-M Designs in order to order stuff because companies wouldn’t send swag out to an individual.

Was bored for a little while today so I made a quick program in Freebasic to produce a Sierpinski Triangle and a some sort of pentagonal fractal. This little program uses the chaos game method to produce it.

seirpinski triangle

seirpinski at 5

I think the result is kind of interesting, I’ll post the crummy little program.
choppy.bas
Nothing special with this, just the result of boredom. You could change the radius and the ox and oy variables to look deeper into the triangle/pentagon.

Well, it’s been a long road but I’m almost at the finish line in terms of the majority of development. All of the parts are mostly made and I’ll begin programming very soon, most of which has been done already or figured out in advance.
Firstly, I started with the board. I had to build it from scratch because I’m not certain of they’ll want more features or different ones, also I simply don’t have the funds to get the printed boards made, those will fit in the top of the unit below the LCD and reflection switch.

viscometer test board with lcd display

Viscometer, assembled on base

So, after this I spent the entire weekend building the parts required to make the rest of the unit. I opened up a few of the tolerances and had to make some changes simply to allow for better fitting afterward. The unit would have been impossible to assemble otherwise

Viscometer with sensor in hand

I have to say, I’m satisfied with the results thus far. The bearing holding the sensor together could be a bit better though. This week I’m going to have to program the unit and hopefully this long saga will be over. Well, at least when I make the 15 units it will be.

While developing the in-process stormer viscometer, one of my goals is to allow the end user to calibrate the device with 3 fluids of known viscosity. With a bit of help from mathematica, I’ve found the formula and for whoever wants it, it’s posted, also for my own future edification. This formula is meant to convert 3 data points of the form {X1,Y1},{X2,Y2},{X3,Y3} into a form of ax^2+bx+c=y. This is probably the fastest way to do this kind of operation on a microcontroller. Here’s an image of the formula

also, here’s a dirty FreeBasic program using it. regress-3point.bas

Also, for fun I decided to do a cubic version. This is in the form of 4 data points {X1,Y1},{X2,Y2},… converting to ax^3+bx^2+cx+d=y

You gotta love Mathematica!!!

I thought I would have nothing to post but I do I guess. I’ve felt the need to really expedite this project now that I am starting a business. I have done a few of the mechanical things associated with it after a major redesign. Today I have completed the design of the board and despite it’s sloppiness, I’m happy it’s done. Now to get it made.

Viscometer Board 3D View

Viscometer Board traces

Like I state in the description, I used the autorouter on this image, I may revise many of the traces so that ripple can be eliminated from IC’s by bringing the caps closer electrically to Gnd and Vcc. This week I hope to finish the machining side of the device, I’ll have to wait for bolts from Fastenal to arrive but it’ll be worth the wait. Here are some shots of the parts so far, note that the main block is made of phenolic, I love this material since it looks kind of like wood but is reasonably machinable.

Machining the block

Phenolic Block Finished

Coming along, main block and holders finished

Just for the record, here is the list of, well electrical features:

1. 16 key Keypad for data entry, mostly for calibration.
2. 16×2 LCD display for seeing alarms and viscometer output.
3. 24V motor, PWM driven with TIP102
4. Light interrupted sensors for top and bottom
5. provisions for temperature sensing
6. RS-485 Out
7. Provision for an external RS-232 board, if needed
8. TVS’ed to the hilt, hopefully this will prevent funny stuff from happening.

Anyways, let’s hope she all works out in the end.

Well, no new project pictures or anything. Summer is almost here and I’m pretty happy about that. I’m going to start at a training course for 8 weeks starting May 11.
The program itself is funded through the Canadian Government or Employment Insurance. This program is geared for people who wish to start their own business but lack the experience starting one. This program also has a 4 month post-class coaching period. From what I understand, they assist with the minutia of business and get you hooked up with financing. This program also allows one to keep collecting EI through the 6 months of the training, but not afterwards.
My idea in this case in terms of starting a business is a nebulous one at best at the moment, however, I think that by lending my skills as a machinist and programmer and technical dude, hopefully I can eke out a living or perhaps even a prosperous business in these difficult economic times.
I think that this program will help give me an introduction to the business skills I lack in abundance. Anyways, hopefully tomorrow will be a sunny day, I want to do my full report on minolta md lenses.

Well, my servos have all come in for a project I’ve been working on. These ones being some cheap Chinese servos that I picked up off Ebay. Here’s a photo of one of them.

Chinese 9G RC Servo Photo

Now that I have them I guess I have no excuse in not doing the project, especially since I bought so many of them, despite them being cheap. In starting my project I’ve decided to offer a PDF of a drawing for the servo since I had no idea how big they were or what they would measure until they arrived, thus, if anyone else wants the drawing, they can use the dimensions for their own purposes.
Here are a couple of pics of the drawing for reference.

Chinese 9G RC Servo drawing

[caption id="attachment_548" align="aligncenter" width="373" caption="Chinese 9G RC Servo Solid"][/caption]

As the project progresses I’ll review the functionality of the servos. After I had ordered them I had read that they are susceptible to outside interference, especially from the likes of human contact around the housing. From what I read, this made the servo “Freak out”. We’ll see I guess, I’m going to make a standard testbed circuit for testing anyways.

So, anyways, for anyone who wants it the drawing, here’s the PDF

Chinese 9G RC Servo PDF

Hopefully someone will find it useful.

It’s been a while since I’ve worked at full steam on the viscometer project. Though now a long way from it’s DIY roots I am making this new version from mostly Aluminum, Phenolic, Nylon and Low Density PolyEthylene. I had to scrap the last version since it would have been too difficult to actually assemble, this one is a little different in it’s overall size and assembly.

Of course it isn’t finished yet as it doesn’t have the screen and top switch attached as well as the outer shell. Perhaps I’ll start making it this week sometime.

In short, I’ve finished the reverse engineering of an enclosure. It was more work than I expected but all of the draft angles check out and the drawing is workable for changes. Here are some pictures.

whew! Doesn’t look like much but it was a bit of a challenge. Looking forward to more challenging drawing projects.

Since my design was accepted in terms of moving ahead on a prototype, I’ve been working first on the board design. I have decided to abandon the PIC18F2620 in favour of the 18F4685. The reason for this change over is due to the fact that the 18f2620 doesn’t have enough I/O to handle the addition of two analog channels and four I/O for RS-485 communication.

This post is more for my own edification and to help me sort out my thoughts on this issue. I suppose for the sake of following my train of thought while sitting here, I’ll outline the specifications, as I think of them.

Overall feature set:
PWM output for 6-24V DC motor.
RS-485 Out – Rec enabled
LCD out
16 key keypad in
2 temperature sensors
LED indicators for power/error
Serial out for RS-232
Input for external reflection sensor
2 inputs for timing sensors

So, thats 1+4+6+8+2+2+1+1+2 = 27 inputs

I found some nice Molex headers that are single row, .100 pitch and is latched. Typically I use the friction based header and housings but it needs to be secure inside the housing and thus I’m trying out the new set. Also I’m going to use vertical out terminal blocks in order to save space inside the unit but not necessarily on the board.

I’m also considering adding an RS-232 port along side the board.

Hopefully this will be the final hurrah!

Now I have to find some suitable DC gearmotors for the viscometer. here are some links, for reference, to some suitable gear motors.
A 300 RPM one from batteryspace, a little small, good low cost though.

A little pricier. This is a cheap chinese one that is on the current prototype.

Not really useful but might have some other uses

Have no idea about these but seems to have a good selection.

Well, this has a been a long few days of work. I have created the ideal rotary viscometer in both terms of price and repeatability. Now, this idea is nothing new but I’m simply happy that it works. I guess it’d be prudent to go in to how it works…

How it works:

The concept is simple. you have a shaft that is separated by a spring, in this case two plastic cups connected by a ball bearing with rods sticking out one side. This shaft is driven by a small gear motor and a set of paddles is attached to the other end. While this is rotating, the difference in the driven and the resisted side is measured with some form of instrument be it a hall effect sensor or a slot type optical transducer.

Viscometer and stand

What I used:

Well, as far as materials are concerned, for the prototype I used blocks of polyethylene to support both the motor and the shafts. The material has pretty low friction properties at low loads and thus I used it as the bearing on the bottom. The actual difference mechanism is made from a high density plastic. I would probably use this material again as it’s light, rugged and easy to machine. For the real unit, I may still use this plastic as it is more than strong enough and it’s easy to machine.

As for the drive I used a design similar to the older designs with PWM motor output, serial output, keyboard input, LCD out and 2 channels of input. This is all controlled with a PIC18F2620 which is more than enough for it’s needs.

The motor itself is a Hsiang Neng gearmotor running at 12 volts. It’s a piece of shit but that’s not important at this stage of the game.

Motor and sensor

So, finally, a desired feature list:

1. RS-485 Out
2. KU and Cp out
3. Multi-fluid calibration, this feature allows the user to select fluids of any KU value and calibrate the unit by entering them in.
4. Easy to use menus. Too often have I seen automation stuff that’s unintuitive. This hould be easy for the operator to understand and easy for the people to use.
5. Speed selection, so that you can use under-powered motors.

Anyways, here’s a gallery of some of the pictures of what could be a DIY stormer viscometer.

Now that I’m working on the viscometer, again, for Endura; I have come up with a few cheap ways of producing the needed results. They may work, they may not. Anyways, pictures and drawings are forthcoming.

“With low enough standards, you can achieve anything!”

“If you aim for the ground, you’ll always hit the mark.”

“If it’s worth doing, it’s worth doing poorly and half way.”

“If at first you don’t succeed. Lower, lower the bar.”

“If it can’t be done quickly, it’s not worth doing.”

………………
Just saying…

For the last few days I’ve been working on the electrical portion of an astrophotography mount for my camera. The mechanical portions were built by my father and I’m handling the electronic portion of the device. Basically, for those who don’t know, this device is designed to allow one to take long exposures of the stars without them blurring due to them moving across the sky. This device moves the camera in such a way that allows for said movement.

Originally, my father and I spent a day working on both the frame and the electronic portions of the unit. I quickly whipped one up with a protoboard I had laying around and a PIC16F690. I used an SN754410NE H-Bridge driver for this design as well. Unfortunately we didn’t finish the project that day, and I wasn’t keen on programming the PIC having to pull it out of the IC socket every time I wanted to test it.

The original defunct board. This board was omitted due to the fact that it had no ICSP provisions.

Anyways, many months have passed since then so I decided to finish ‘er up. This time though I wanted the underlying design to be flexible enough to handle any configuration of “barn door” and to allow for nice methods for both calibrating and homing the device, whereas most DIY methods are rudimentary at best. The reason I want to make it more robust than needed is due to the fact that I believe that a nicely finished electronics board kit may sell quite well, or perhaps even the entire unit if done in a low-cost, high quality way.
Here are some of the planned features:
1. Multiple configurations built-in for both screw pitch, motor step angle and “barn door” configuration
2. Homing and End Range Switch provisions to allow for homing of the device and mechanical damage prevention.
3. Support for 12 and 16 button keypads.
4. Support for 8×1 or 16×1 HD44780 LCD displays. I choose these because they’re cheap and formatting for this style guarantees compatibility.
5. Multiple drive options, Full-step, Half-Step, Strong movement, weak movement.
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Anyways, Here are some images and descriptions of how I put it together, up till now. As of this writing, it’s not finished yet. It will take some time methinks.

First, I took some Stripboard and planned out the pinouts and connections. Stripboard (or veroboard) is my favorite since it’s so damned easy to plan. Despite there being a great many other protoboards out there, veroboard has been the most useful, for me anyways.

Planning it out

Starting the board

Halfway done

Board pretty much complete

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There were a few kinks to work out but not many, despite how messy this board is.
It took me a while but I got the keypad, LCD and Stepper running. It didn’t take very long for the LCD and keypad since I’d already developed my own libraries for those functions. I then played with the stepper motor and got it working.

Astrophotography electrics working with keypad, LCD and stepper motor

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Now, to mount it in the enclosure. I just happened to have an ideal enclosure and a sealed lead acid battery from princess auto. The battery charged fine and I think it will serve quite well to run the stepper (This motor draws about 200-400ma depending on drive configuration). Here’s what it looks like as of today.

Electrics in Enclosure

I’ll have to give the enclosure some rubber feet since the mounting screws jut from the bottom but that’s cosmetic at this point.

Anyways, I’ll report further progress, as usual, on my blog here.

Here are some interesting links
http://www.keteu.org/~haunma/proj/barndoor/
http://www.cs.uiowa.edu/~jones/step/types.html

Comment if you wish.

I bought a couple of keypads of Ebay some time ago and since they were so nice, I decided to use them in my latest project. Since there are no data sheets for this, that I could find, I checked the wiring myself. The unit is from Bally systems, made by ACT and has P/N 105123D

Here are a couple of images of the unit.

And here’s a connection table. Keep in mind that the connections range in resistances from 30 to 100 Ohms.

	Pin 1	Pin 2	Pin 3
Pin 4	CLR	0	ENT
Pin 5	3	6	9
Pin 6	2	5	8
Pin 7	1	4	7

Many years ago I used to make maps for Doom. There is still a community going strong for making maps and now with modern source ports and editors, sometimes I dabble in making a new maps. Anyways, here are some screen shots from what I made. I’m certainly not very good anymore, it takes practice to make neat looking maps.

Maybe I’ll make a full map one of these days, though, looking at some of the elaborate maps that the community is putting out, I’m not sure I’d have the time to compete with such standards. It’s fun nonetheless.

Since I’ve started playing around with writing games again, I’ve been interested in old school sounds. These things can be hard to come by these days since a lot of the older sounds were pure square and triangle waves.

I found a couple of programs for creating these sounds. Both are windows programs
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SUBSYNTH.ZIP
SFXR.ZIP
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So far, they seem to work OK. I’m just keeping them here in case they disappear someday.

Well, out of boredom I’ve created a little game called Astrosmasher. Nothing special really, I just wanted to see if I could make a game look like an old Atari game. I think I succeeded in some ways

Astrosmasher is a partial clone of an older colecovision game bit I got bored with it pretty quickly, I think I’d like to write games that are a little more fun despite the fact that I have no artistic ability.

Anyways, here are some screen shots and a like to the game. The game requires windows 2000+.

*****DOWNLOAD ASTROSMASHER*****

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Consider this game, for the most part, incomplete. I got bored with the idea and made it workable. It is a hard game though. My high score thus far is 35100. Give ‘er a shot.

Well, It’s been a number of days since I built the unit and all’s been tested. Here is a picture of some of the data from my living room over the past several days. The purplish is the temperature and the lighter one is the ambient light. You can see that as the light levels get higher, the furnace stops, thus the temperature stops fluctuating.

The living room temperature as seen over 6 days

Sorry about the small scale of the temperature graph, the graphing program is still a work in progress.

So, since I’m really bored I decided to build a device that tracks ambient temperature and light levels. While this may not seem very interesting, I suspect the relationship between the two, while not directly linked, will be interesting especially when placed outside. Well, I suppose I’ll put a few pictures up and outline some of the stages I went through to get it to this point.

1. Prototyping.

The initial version of the sensor, using older stuff from viscometer project.

This didn’t take long. I already had a board with a single supply opamp (JRC 7014D) on it that was already set up for the LM335Z temperature sensor. I used a bread board, as can be seen in the picture, and used a messy bunch of wires coming from the PICKIT2 to the MCU. I chose a PIC16F684 for this job since it has some analog channels and it doesn’t have too many pins.

2. Checking it out. In order to see if the Voltage range will allow for freezing temperatures and room temperature, I had to test it with some snow.

Cup o' snow to check and see if the Opamp is biased correctly

Temperature check with the IR gage

The voltages swung just fine with a bit of extra range. I have about 50C to work with in range, good enough.

3. Making the board. For this I used a board from measurexplorer. I have tons of these but haven’t had much luck using them. The only ones that have worked well for me are the ones with 3 holes per pad. Anyways, here are some pictures.

Start of prototyping the board

[caption id="attachment_397" align="aligncenter" width="400" caption="Finished Sensor board with both light sensing and temperature sensing"][/caption]

Anyways, This board took me a couple hours to make but it works well and required no rework, thankfully. You can see both the LM335X (TO-92) and the CDS for sensing the light. This board interfaces to an RS232 board that I’ve made and that I use for some of my other projects.

4. Getting ‘er running. While the unit itself is already programmed in terms of the MCU. it needs some adjusting for voltage on the pot and that’s about it. now to affix it to something so it doesn’t move around.

RS232 and Sensors glued to a board

[caption id="attachment_400" align="aligncenter" width="400" caption="Tracking it on the computer"][/caption]

As you can see, I simply used hot glue to affix both the RS232 board and the sensor board to the block of wood. Its a temporary arrangement while I come up with a good enclosure for outside. I brought my old laptop out into service for this project, works well just for collecting data.

Anyways, here are some images of some collected data.

Living room temperatures (click to see description)

Basement (click to see description)

Well, so far so good. Now I’ll make the enclosure for outside and improve the sampling. hopefully I can leave it out all spring/summer and see the patterns.

Well, I was trying to solder some extra thick peizo material, having very little luck when I realized that this could be solved very easily with some sort of conductive adhesive. So I set out to make some. I’m posting the steps for making a conductive adhesive for posterity and in case anyone needs to know. It’s not difficult though I have tried a few different methods and this one is the best.

1. Find your glue, preferably one that requires drying or curing, not anaerobic adhesives like Loctite (cyanoacrylate). I tried a couple of versions of Loctite and found that the conductive medium would merely clump together, making an oatmeal-glue. You can use adhesives like Rubber cement, 2 part epoxy or even white glue (polyvinyl acetate).

In this case I used two-part epoxy. It has a long cure time and its fairly rigid.

A small sample of the epoxy

Nothing much to see there, since I wanted to use only a few drops of actual adhesive, I only mixed a gram or so of the stuff.

2. Prepare the medium. In this case I used a conductive graphite powder and iron filings. If you’re going to use iron filings, magnetize them first by letting them rub on a magnet, then force them off and into the graphite mixture. Beware that using a water based glue can make the iron filings oxidize.

Anyways, if you don’t have any graphite on hand you can crush up some pencil leads in a crucible or on something that will allow you to make the graphite as fine as possible. And in the event of not having any iron filings, like me, do what I did, grind or file down a piece of steel or an iron nail. make sure they’re magnetic.

This is the graphite/iron mixture

Now, you may ask “Why iron, and why magnetize it?” Well, the iron provides low resistance paths through the adhesive and when you apply a magnetic field to the iron filings, they align themselves to the field, thus you can create a lower resistance path. I’ve reduced the resistance with this method by tens of KOhms based on the little I’ve done this so far, your results may vary.

3. Mix the glue and medium. Well this is a pretty simple step. The only thing you’ll many though is to add enough of the medium to make the overall adhesive almost clumpy, mixed to the point of saturation. This way you can ensure conductance.

This is the mixed version of the glue/graphite/iron filings

4. Application of the glue. Simply apply the glue however you want, wherever you want. You’ll get less resistance if you place the two conductors as close to each other as possible though. Also, you’ll want to place one or two magnets, polarity aligned to the connections zones, near the adhesive. This will make the iron (if you used it) move slowly into lengthwise position between the two conductors.

This is the peice of peizo material attached with epoxy.

Anyways, to be honest, I’ve only tried this formula a few times and did it entirely by eye, therefore I can’t give any exact values. But, thus far it works for me. If it works or doesn’t work for anyone else, feel free to comment.

A while back I bought some lcd displays from a dude on Ebay. After I recieved them I found that I couldn’t find the appropriate documentation. Well I found some documentation so I post it here for posterity or if anyone else wants it.

ktms1201
upd7225-ap-note
s14308ej6v1ds00

These are 12 position, 7 segment displays. They may come in handy someday so I’ll try them out later.

KTMS1201 from Modulehouse
UPD7725 controller

I was a little bored today so I decided to draw a valve. While the dimensions are entirely drawn from my head and the valve itself wouldn’t be very efficient, I like the look of gas compressor valves. It took me a couple of hours to draw but they look OK.

I didn’t tag them or describe them. There is a seat, a guard and a valve plate. I omitted the dowel pin, bolt, center nub and lock nut. I just wanted to see what it looked like in solids.

Been working on a new version of the rotary viscometer, after many design changes, the result is this. A rotary viscometer bridged with a rotary reaction strain gage. Guess it’ll work. Here are some pictures.

I’d say a bit more but I’ll wait until the design is a little more fleshed out, and of course, remember that this design isn’t finished since the motor at the back obviously doesn’t float in mid-air.

For the last while I’ve been in a bit of a creative funk. Troubles at work and the the weather have made it difficult to concentrate on the things that I like. Anyways, perhaps while I have some time off I might make use of it to do some stuff. Don’t know really.

That brings me to my next topic. What I should do.

Firstly, I think I’m going to start taking more pictures of Edmonton again and post them on Panoramio again. Frankly, this is the reason I started taking pictures in the first place was to provide images of Edmonton for whoever wanted to look and explore both the nice parts and boring parts of our city.

Secondly, I’ll finish that fucking clock. Really not much more to do it it, just make it so you can set the time.

Thirdly, focus on building a working vibratory viscometer. It’s the ideal way to measure Krebs units in an environment as harsh as paints and it will be substantially cheaper.

Anyways, End of Line.

Well, I’ve been looking around at torque sensors and found some interesting information. For one though, they are NOT cheap. Keep in mind that these are higher sensitivity sensors but it doesn’t seem to have an overwhelming bearing on the overall price. for example.

Optical, high sensitivity sensor, ~$6000
Magneto-elastic sensor, ~$2000
Strain gage based, ~$4300

While this is expected, it’s still quite a cost on a per-unit basis. interesting.

Another little tid-bit I picked up is this.
Magneto-Elastic sensor document

Anyways, I’ll keep looking for a cheaper unit, though, I doubt I’ll find one cheaper than the unit I developed. Perhaps I’ll machine a small enclosure with precision bearings and develop a more robust and practical design. I have some conductive graphite for the brushes in order to reduce noise and the brushes could be replaceable. Might try it.

Well, for the past little while, I’ve been working on a bizarre clock made with LEDs glued into a dollar-store cookie sheet. I got the idea just out of the blue and decided that it would be fun to build. Now, it’s nearing completion so I figured it’d be prudent to document the miserable contraption. I guess I should go through the steps it took to get this thing running.

First, I took one of those dollar store cookie sheets and drilled it through for 40 LEDs. 12 for the hours, 12 for the minutes, 5 for the seconds, 5 more for the div/5 minutes and five more for the outside and the PM light.

Drilling it wasn’t much fun but, when it was finished, I started to insert the LEDs with the grounds all towards the outside of their respective circle. Then I mixed up some epoxy and drizzled it over the backs of the LED’s. Unfortunately, the epoxy didn’t hold very well on the other epoxy surfaces so I used hot glue to tie them down.

As you can see, I labeled it in reverse of the other side so that I could get ‘er working. Thus started the long job of soldering the whole thing.

The image show isn’t the complete one, but it took me several hours to solder it all together. I used 7 groups of 6 LEDs in order to display the image. In this case I used the 7 groups for the duty cycle, thus a 1/7 duty cycle was used. Each of the 7 groups is fed ground through an MPSA13 Darlington transistor. Here’s a picture of the board that controls it.

Pretty fucking ugly, I know. But it works and I used an MCU (PIC18F4685) that was a little overkill but that’s fine, I’ve got quite a few of those. Anyways, so far so good, though it seems a little impractical as a clock and I think I set the rings of the minutes and hours too close together. Oh well.

So, after doing a bunch of work on the rotary strain gage it’s been declared incorrect. Oh well. Here’s the new concept, although not my own idea, were going to rebuild the entire concept around the notion of a dynomometer. First we’re going to place the motor inside of a housing that allows the motor to move freely with the help of large ring bearings, then we’re going to bind the motor in place with load cells.

While this concept may work, I feel as though it’s lower end repeatability and accuracy will be compromised and will be greatly subject to temperature differences as the bearings heat and cool from ambient and mechanical sources. But perhaps I’ll be proven incorrect.

Here are some images of the idea.

I’m going to keep working on my own sensor design in the meantime, it may come in handy someday.