Sun Computer

Click HERE for pics
Components:

1. Teensy 3.1

2. Solar Sensing device, SolarMEMS, ISSD60

3. GPS, Adafruit Ultimate GPS Breakout, MTK333

4. LCD, 20x4

5. SD Card

6. Potentiometer

1. Teensys are great. They don’t have the USB data pins “broken out” so i had to make a little extension out of the main port so i could have a durable USB-B port on the outside of the box.

2. The Solar Sensor itself was trouble. It says it uses the Modbus standard. NOPE. First the differential A and B lines were swapped AND labeled + and -. The sensor data registers began at 1 instead of 40001 (at least i got an error response). The first bits of the response were always corrupted, but I knew is was static data about the model number so i modified the modbus arduino library to return the correct bytes. phew!

3. I used the TinyGPS library for easily decoding NEMA messages.

ARDUINO GPS WARING. NEMA messages are often more than 64 characters long. Most Arduinos and in my case, Teensys, have a Serial buffer only 64 chars long and need to be configured to be longer. On a Teensy, the Serial core files need to be modified.

Originally the box Is supposed to mounted on the hood of a car, possibly with a suction cup. The box is water resistant in case it rains.

Originally The box was to have internet connectivity and serve its data to a MySQL server. I worked with both WIFI and Ethernet modules but ran into issues with both.

I tried to use a stock ESP8266. After a week of work, I determined the AT commands were too buggy to be reliable. For example doing a AT? type read would change some seemingly unrelated setting. Other people confirmed to have these types of problems, good for a quick project but the ESP8266 needs better firmware, updates may be out by now and more custom firmware exist everyday.

I tried to use my Ethernet and had luck! it was reliable to any type of data stream interruption. however my particular Arduino Ethernet shield knockoff must of had its reset pin zapped! because neither high or low pulses reset the device, only touching the reset pin with my finger made it reset. :)

The protocol called Telnet is the standard for shuttling ascii over internet, since 1973.

The box is powered externally through the USB port. I find this is the most compatible method for any situation. A wall charger, PC USB port, Car charger or USB backup battery can all be used to power the device.

There is a TERRIBLE bug i cannot track down, it only happens when other people are looking at it! The LCD will become completely corrupted. it seems to happen more often in a car where there is a lot of vibration. The only way to fix it is to reset the box. In professional product design for anything that will be in a vibration environment, vibration tests are done using a machine like this.

4. The Fact about LCDs: When displaying things on standard character LCD, the screen needs to be cleared between every update to erase extra chars if a displayed number shrinks in number of chars. However clearing and redrawing a 20x4 screen can take long enough that it flashes annoyingly. The easiest remedy is to increase the data rate. A direct hook up instead of a I2C backpack can increase transfer rate and reduce the flicker. Somebody needs to write a library to manage the screen to avoid having to clear and redraw the whole thing, I can't be bothered to do so though, i'll just will use an OLED screen next time. ¯\_(ツ)_/¯

5. For a microSD adapter slot, you can solder directly to a generic microSD->SD adapter.

ARDUINO SD LIBRARY WARNING. A frustrating “bug” i ran into with the default Arduino library is that it only accepts TEN character filenames. An example is “data.txt” which is 8 characters! I recommend using a different library. I don’t think you need a file name extension as long as you open it with a text editor, example “datasheet” will make a file with no extension which is ok.

6. The Potentiometer changes screens. The code includes historesis to prevent jittering between screens.

This device has proven useful in getting quick measurements of The Phenoix's performance before we began tearing it down and refurbishing it. Most prominently doing coast-down tests with the GPS and testing the Array output power. Measuring 964 W/m^2 one day gives us 760 W from the array, we can extrapolate the max output power if the day was 1050 W/m^2, 828W max from the array

Phoenix Solar Racing

Phoenix Solar Racing Website - Note: I may or may-not endorse anything our site says :)

---->>>  CLICK  HERE  FOR  PICTURES  <<<----

This post is just a few words about my current job and life. Without this post, the future projects I post won’t make much sense. :)  My first semester At Oregon State University, I joined to the OSU Solar Vehicle Team. The team's solar car was “out of town” at the Abu Dhabi Solar Challenge . The next semester I tried to become more involved. When the car returned, I came to realize what a monumentally challenging and exciting team project solar car racing was! I took on any responsibility they would give me and began learning everything I could about solar racing.

I built a little Solar Sensor for the team. It was for detecting solar power(W/m^2) and XY sun angle, ahead of the solar car while it was on the road.  The box had an GPS to couple the solar measurements with position data. The solar sensor module itself was donated to the team as apart of Solar Mems sponsorship of the team. It was a huge pain to get working as it used RS-485, and did not follow the RS-485 standards very well. I really don’t recommend it unless you get it for free like we did. :(

Midway through the project, the Electrical Lead I was making it for stepped down. I offered to lead the electrical team and I was elected!

At the time, the returning car, “The Phoenix” was going to be put on a shelf, and an all new Vehicle built. Designs were for the body were finished and tested but ultimately the ending school year and lack of engineers on the team led the New Vehicle project to fall too far behind schedule.

Our deadline is the American Solar Challenge 2016 in July of that year and instead we decided to refurbish the ageing “Phoenix” vehicle. I am designing an all new electrical system for this Phoenix 2.0. It is my hope that this electrical system will also be used in any future vehicle the team makes. I am making sure there is plenty of documentation, flexibility and foresight to do so.

Some things Solar Racing dwells in:

1. High Power Density Batteries
2. Super High efficiency motors and controllers
3. High efficiency Solar Cells and Maximum power point trackers
4. Sensors for energy statistics and Computer number crunching
5. Lightweight designs with carbon fiber, Aluminium and Titanium.
6. Aerodynamics

I’ll make a post about our Phoenix 2.0 “Spec Sheet”

Some other things that have happened:

The Oregon State University Solar Vehicle Team was mysteriously let go by the Oregon State University: College Of Engineering. Our team is now called “Phoenix Solar Racing”. We lost our workshop space, ~10 grand annual sponsorship, legal support, Insurance support, and the nonprofit status that allows sponsors of our team to receive Tax Deductibility on their donations.

The new workshop is now the two car garage at the house I am living at. :)

The Mechanical Lead of our team dragged his feet for months and nobody objected when i took over as Mechanical lead. Now I share Mechanical Lead responsibilities with another teammate.

That's my full time Job, I get payed in the chance to do crazy mad hax with a team of crazy mad people!

Yusynth VCO - The Companion Text

I made a guide of important tips to accompany The Yusnth VCO guide. If you are building this analog synthesizer module, and need help trouble shooting or just want to know more... You can download the PDF from Google drive.


Good Luck!

Yusynth VCO

Click image for more photos             Yusynth.net

The most important modules in an Analog Modular Synthesizer are its oscillators. Without an oscillator, there would be no sound to transform and subtract from, (hence subtractive synthesis). Of coarse you could use another source of sound like a guitar or music or a human voice, but these sources have the disadvantage of not being able to be precisely controlled into constant tones and notes.

Naturally an oscillator is the first module you would want to build. Many DIYAMS websites offer their versions of a VCO. Vee-cee-oh stands for Voltage Controlled Oscillator, meaning the pitch and other functions of the oscillator can be controlled by a changing voltage from an external source. CGS synth, Music From Outer Space, Thomas Henry - Birth of a synth, and Yusynth are the best producers of DIYMAS instructions and all offer one or more VCO. I have chosen Yusynths VCO for many reasons, but it might not be the one for you. The Yusynth VCO has many features, an all Op-amp construction, a single sided PCB layout, and Mr Yusynth has a disposition to monetary gain.

Panel Design:
   Jacks:
Originally I bough a pack of 40 mono input jacks and plugs for the front panels before I remembered a better option. The Tinsizer, in the interest of compactness, uses 0.1 inch, double row headers in concert with solid core wires to provide patching. This is the plugging type I chose for my synth but I incorporated ground connections and shielded cables. The bottom row of the double row header are all grounds and the cables are two pronged, but for shorter patches I can just use bits of wire. I put a lot of thought into how these jacks function because of course it has to be the same on all the modules.

   Attenuators:
The three lowest knobs are attenuators which turn down the volume of incoming signals and only do anything if an input signal is fed through them, otherwise they sit dormant. I only have attenuators on my VCO's because the were the first modules I built. All subsequent models will have direct inputs, and attenuation will be patched in using external attenuators.


Personal electronic Mods:
    LFO mod:
One of the reasons I chose this VCO was based on my theory that it would be able to achieve very low frequency's without much modification. I was able in the end to implement a switch that changed the VCO from a 4Hz - 12.6kHz audio range to a 0.047Hz(21s) - 13.3Hz LFO range (with external voltage input). These ranges are close to what I want and sound grate, it takes a lot of fiddling around with component values. I will go into copious detail in my next post about the circuit.

   Possible future mods:
There are a number of small problems that I may make a fuss about in the future. frequency ranges, waveform purity ect, I have a compulsion to make things perfect but that is becoming less important and rewarding then building new moduals. However would like to implement some new wave form outputs. first would be a Ramp wave, the inverse of the saw-tooth wave would just take one opamp to make and would be very useful in LFO mode.

A serious mod I want to make is a Triangle/Saw Skew output and control. One of the wave forms of the Minimoog is a combination of its triangle and saw and helps to give its signature sound.  I may also attempt to make the mix between saw and triangle, voltage controlled, a unique feature I have not seen exactly on other VCO's out there.
   

Minimoog Tri/Saw, the missing waveform from my VCO

Waveform info graphic of the Yusynth VCO

Next time I will go into detail about building, troubleshooting and moding this module as sort of a companion text to the main instructions. see ya!

Mini Synth

I have begun my most ambitions project yet, to build a Modular Analog Synthesizer, It has been a dream of mine to build, design and own a Analog synthesizer ever since I watched a group of Youtubes from a user I unfortunately cannot remember the name of. He began his videos by walking down the stairs into his basement saying "Hello boys and girls!" with a cigar between his lips. It was sometime in 2009 when I watched these videos and I think his username had "dolphin" in it. Dang I have searched high and low.

Anyway the time has come in my life to begin building this fantastically complex electronic machine. I began back in October 2014 and will be playing a lot of catch up with these posts and videos. It is at a time when my knowledge is at an sufficient level to actually be able and build it, while also learning a whole lot while doing so.

The Synth DIY community is small but totally hardcore. A french scientist username:YuSynth has an extensive library of do it yourself instructions for all the basic electronic synthesizer modules. Each module page has schematics, single-side PCB images, tuning notes, wiring guides, panel graphics, almost everything you need to build your own modules. However, having lots of electronics trouble shooting experience is actually very necessary due to the complexity of these analog modules.

Although Yusynth has designed the modules, but its up to the DIYer to choose the modules they build, it makes a big difference in how the overall synth operates and sounds. The physical designs of the control surfaces I design myself, along with any circuit mods.

The inspiration for my synth.

1. Minimoog
1.  first modules will be built will mimic the futures of the Minimoog model D, a famous Moog synthesizer. The features Minimoog  are:
1. 3 VCO's with Tri,Tr-Saw,Saw,Ramp,and Pulse, can be tuned to a very low pitch
2. A Noise Generator with Pink and White noise
3. A Mixer
4. A Minimoog Filter (The soul of a Minimoog)
5. 2 ADSR's, one for the Filter and another for the VCA
6. A VCA
7. Glide
8. Another feature similar to the Minimoog will be the sloped control surface, which is very natural to operate.
9. Wood
2.  non-Minimoog
1. This is no faithful recreation of a Minimoog, but rather my synth just is coppying its tonal concept. There are many types of synthesizers, from 555 timers to software synths, but the Minimoog concept stands on its own. That being said there are additional things I would like:
1. PATCHability, The Minimoog has an almost all built in, switch based patching and is very limited. This makes patching as easy as a flick of a switch which is great when your jamming out. However I would rather have an endless possibility of stupid noises.
2. NO KEYBOARD. no pitch bend and and mod wheel. I might build a Jammer Keyboard but the jurys still out on how notes will be played.
3. NO LIGHTS, no screens, the only indications are the positions of knobs and switches. it helps bring the daemons out.
4. And finally BE AS ANALOG AS IS REASONABLY POSSIBLE. Analog lets stranger things happen. A digital synth can make the same wave forms of an analog synth but is immune to the sea of imperfections. It is also my desire to learn analog electronics and I can't do that if there isn't any. The module I am designing is very digital but only because it is much more practical to be and I'm working hard to make it sound as analog as possible.

An artiststic rendition of my future synth in Google Sketchup

This is the final drawing of my synth in Sketchup, Without all the wizbangs of course, I will talk about it more when the time comes. Next Episode is on my first DIY Yusynth Analog Modular Synthasizer Modual... see ya