Weather Station - Introduction

I have decided to dive into the adventure of building a functional automatic weather station(AWS), there are a lot of these projects on the web and are easily copied and pasted, but I feel this is not worth doing because you don't really learn anything from this.

What I plan to do is write a series of blog posts detailing the build process of the weather station, describing my build of all parts separately and then finally bringing it together in a final post and a permanent web app with forecasting and logging of weather for where I live.

I will be designing the station to be completely self-powered, this will be done by using a wind turbine and a solar panel, these will charge I am thinking of 3V coin cells, each one possibly powering a set of sensors and the micro.

The weather station will send the collected data to the base station located in the house and will manage storage and the method of either hosting or pushing the data to a storage site.

The station will contain the following functionality:

• Temperature
• Humidity
• Wind Speed
• Wind Direction
• Barometric Pressure
• Light Intensity
• Visibility( or a sort of mist sensor)
• Rain Gauge
• Wireless Transceiver

I'll add more as I find other interesting stuff to monitor.

The base will have:

• Display for sensed values
• Wireless Transceiver
• Storage
• GSM to upload to server if needed
• A display for the current or predicted weather
• RTC

The Transceivers will be either 434MHz or the 2.4GHz range, although its only < 9m of distance between sensor and base(line of sight).

I also believe I might have a use for this site http://www.weewx.com/, it produces graphs and pages for weather station data and is LINUX compatible! Therefore the next logical thought is to run it on a Raspberry Pi which the system supports which will be awesome. 

Tiny Bot

This has probably been done to death on the blogs but I was inspired by the born 2 craft site. Mine needs a bit of work in the code but I generally prefer to do something from scratch by myself after seeing an idea. Mine is also a bit larger as it is veroboard.

Design

The parts are all hacked off of other dead RC toys and boards, ATTiny85 is the only thing I paid for, makes me happy. The system uses a small LiPo striped from crashed mini RC helicopter, nice and light. The board layout was worked out in building, working around the socket as it was meant to be a 8 pin PIC proto-board. 

The wheels were made from ABS sheet, using a circle template at 23mm. Using the four centre marks on the diameter I drew between opposite ones to get the point to make a hole for the shaft, I used a dividers point and checked every now and then to see the fit, just push on with reasonable pressure. 
I used marine silicon to create a tread. This is done by running two strips along ABS sheet at the distance of the wheels, and roll back and forth.

The battery is charged by a full spec LiPo balance charger through the headers, the switch is moved towards the header toput in charge mode.

Some build pics, some:

Underside

Front View

Hardware

The design of the circuit is similar to the born 2 craft, but I made some modifications.

I added the flyback diodes to the two motors, I skimped on those to begin with as there was not enough space, but after changing the transistors for both motors I added them. The PCB layout is my design.

• Transistors are BC817-40
• Diodes are 1N4148
• ATtiny85/45
• Small model motors
• 0805 resistors
• LiPo 3.7v
• Switch SPST
• Wheels: ABS, 23mm dia.
• Some copper wire, varying thickness

Schematic

PCB

Code

/*
Tiny Bot: an LDR based light following robot, or avoidance bot
 if you switch the drive function around.
 Hardware is based off the Light Bot by born 2 craft

 TODO:
 Add IR control
 Clean up code
 ##############################
 Written by:
 Reece May 
 rev1 12/15/14
 https://ziggyelectronics.blogspot.com

You may use the code and modify it as long as you keep the above
and make edit notes bellow and put it on github here:
https://github.com/ReeceM/Tiny-Bot.git
 */

#define Rmtr 1
#define Lmtr 0
#define Rsens 3
#define Lsens 2
#define drive_time 100

int Rav, Lav = 0;

void setup(){

  pinMode(Rmtr, OUTPUT); 
  pinMode(Lmtr, OUTPUT);
  pinMode(Rsens, INPUT);
  pinMode(Lsens, INPUT);

}

void ADread(){
  Rav, Lav = 0;   //clear the average to prevent errors

  for(int q = 0; q < 20; q++){ //loop to create average

    Rav += analogRead(Rsens);
    Lav += analogRead(Lsens);
  }

  Rav /= 19;
  Lav /= 19;
}

void drive_RIGHT(){
  digitalWrite(Lmtr, 0);

  digitalWrite(Rmtr, 1);
  delay(drive_time);
  digitalWrite(Rmtr, 0);
  delay(drive_time);
}

void drive_LEFT(){
  digitalWrite(Rmtr, 0);

  digitalWrite(Lmtr, 1);
  delay(drive_time);
  digitalWrite(Lmtr, 0);
  delay(drive_time);
}

void loop(){

  ADread();
  if(Rav < Lav){
    drive_RIGHT();
    //drive_LEFT();  //use this to avoid light
  }
  ADread();
  if(Lav < Rav){
    drive_LEFT();
    //drive_RIGHT();  //use this to avoid light
  }
}

Links
https://github.com/ReeceM/Tiny-Bot.git

3D PCBs

I have finally found a very good plugin for generating 3D PCBs. I found it on the Eagle Cad page, this took me to Eagle Up. Its got good directions on installing the plugins, even for me, ha. There is really good support from Jerome, the dude who wrote it, this was really helpful for me. 
Add something to this and you get a complete PCB rendering package. This is done by downloading MaxWell Render for SketchUp, as suggested by Jerome, this gives great results. the two pictures are of my redesign of the Little Wire for single sided home brew PCBs.

   

My new Plane!!

My new plane is a Fly Cat X-75 delta wing EPO plane. The kit was an ARTF style with ESC and brushless, but I had a lot of fun with the power-train. First the ESC was not working, get replacement, ESC makes smoke signals on bench testing (not even running), I then got a higher spec'ed one from my supplier and finally on the maiden the motor rattles around not cool. 

There is a brief video at the end and in those few seconds of panic I found my plane has a good glide angle and very responsive even when there is no thrust.

The Box...

The contents

Neatly rapped up.

Fuz

Tail feathers

Wing

Launch-grip and landing skid.

Supplied goods 

Together but Not.

Glued up and tagged.

After bench runs, highly under rated ESC

Cooked voltage reg. and 

the control IC's

New !40A! ESC and it works

What it looked like before flight and after.

The funny noise was the loose motor I sorted that out by adding shallow dimples on the lower part of the stator.