Instrument Data Receiver and Display

This was a lot easier than I had imagined. I followed the Ladyada LCD tutorial and her xBee tutorial. I used the code she provided a long with the liquidcrystal library example sketch which you can find under Arduino 0022 File>Examples> LiquidCrystal>HelloWorld. To this point I can type on my computer in terminal and it will show up on the bright blue display. The connection is wireless between 2 xBees. The xBee connected to the computer used and FTDI cable and an adafruit xBee adapter. The computer just has terminal running using this tutorial. (If you want to connect to your xBee using a terminal on a Mac here's how.) The second xBee is pictured to the right.

NewSoftSerial, Attachinterupt() and Pins 2,3

It's code time... I've been cutting and pasting code together trying to get everything to work at the same time. I'm using a em-406a GPS on the Adafruit GPS shield. I have 2 photogates that need to use the attachinterupt() function. The only digital pins that are setup on the Arduino UNO for attacheinterupt() are 2 and 3. The GPS shield uses digital 2 and 3 for GPS communication using NewSoftSerial. So I tried moving the GPS to other pins, 8 and 9 worked. Now pins 2 and 3 are free for my photogates.

Photogate RPM Sensor Testing

I have to paddlewheel setup on the stern and plugged into the arduino UNO. I'm getting consistent analog readings of; 20-30 for OFF and 700-900 for ON. The digital cutoff point is around 400. If I take it outside ambient UV light will cause the OFF readings to jump up to 200-300 so I'll need to build a cowling to go over the whole apparatus to block out ambient light. I used the RPM photogate code available here to test the sensor's digital readings.

Paddle Wheel on the Stern

I have the photo interrupter all wired up. With the paddlewheel in place and painted black it works really well. right now all I get is RPMs. But I'll calibrate it with the GPS soon.

Soling 1M Sailboat - ShortCircuit

After 3 months of building I now have a sailboat. The mask is about 5ft high and the boat is 3ft long. It should be a great platform to test my electronics. It is radio controlled with 2 channels, for rudder and sail position. The sails can be pulled in or let out so that you can sail from close hauled to directly down wind just like a full sized sailboat.

Photogate with 5ft of Servo Wire

Its been quite a while since I last posted to Arduskipper. The project is still alive. I have been busy building a 3ft sailboat as a platform for the project.

The anemometer will be mounted on the top of the mast. The mast is about 5ft tall. So I put 5ft of servo wire between the breadboard and the arduino to see if the added resistance would change the readings from my photogate sensor. IT CHANGED! A LOT!

A phototransistor plugged into the analog input will give readings of 0-1023. If you plug it into the Arduino's digital input the break point between on/off is around 400. With the sensor plugged directly into the arduino using a 10K ohm resister I was getting ON values of 900 and OFF values of 100. With the 5ft of extra wire that added quite a bit of resistance so I put a 470k ohm resistor in parallel with the 10k ohm resistor to get the same on-900 off-100 analog values.