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[on:]

Hey guys,

  I need a bit of help figuring if my project is feasible in arduino, and if yes; the better ways to proceed.

  I am trying to build a wireless system, with sensors sending data to a range of displays (only 1 for now) or computer(s) (eg, pc + phone).

  The sensors I am thinking about are a 6-DOF and a GPS, display is a LCD (parallel); I currently have this working fine all linked to an Arduino (6-Dof using newsoftserial), Gps on serial, Lcd (an Hitachi but thinking about some 7-digit through a max7219), also logging data to an Sd card.
 
  My next step would be to have the LCD split from the Arduino, so the sensor box can be fixed somewhere down below (on the boat), and the LCD with me outside. (GPS will be fine down below).

  From what I understand (reading through the forums and the net), the LCD not being serial, I'll need an arduino for sure on the LCD side, am I right?

  On the sensor side it looks a bit more complicated; both gps and 6-DOF are currently linked to an arduino, but each send data serially. So I could get two wireless modem (right word?), hook them to each of the sensor.

  Questions:
  1) Hooking up a GPS to a wireless makes sense? fast enough for the data? (GPRMC nmea data at 5hz?)
  2) On the sensor side, it could be between 2 modems + 0 arduino and 1 modem + 1 arduino.

  Along with the LCD display, I would also like to access the wireless data over a computer (pc or android)

  Questions (cont.):
  3) The big one; what kind of wireless protocol is best for what I am trying to do? (Xbee, Wifi, Bluetooth, Radio), I am getting a bit confused on what's available.

Thanks,
Nico



 

[Reply #1 on:]

From what I understand (reading through the forums and the net), the LCD not being serial, I'll need an arduino for sure on the LCD side, am I right?

You can buy a serial LCD and have longer cables (baudrate should be adapted), optionally use RS485

  Questions:
  1) Hooking up a GPS to a wireless makes sense? fast enough for the data? (GPRMC nmea data at 5hz?)

Arduino should be able to handle this, and that said, you can allways decide to send only 1 GPS sample per second to display as you cannot read all that info at 5Hz constantly. Furthermore it will not change that fast (unless your ship is a spaceship?

2) On the sensor side, it could be between 2 modems + 0 arduino and 1 modem + 1 arduino.

Think you do not need a modem.
Furthermore you need to check NewSoftSerial library and you can make multiple serial ports.

  Along with the LCD display, I would also like to access the wireless data over a computer (pc or android)

  Questions (cont.):
  3) The big one; what kind of wireless protocol is best for what I am trying to do? (Xbee, Wifi, Bluetooth, Radio), I am getting a bit confused on what's available.

Have you though about wired ethernet on your boat? How much metal is there on your boat (blocks/influences wireless protocols.

hopes this helps,
Rob
Which country are you from?

[Reply #2 on:]

Hello Rob,

  Thanks for the answer, I am currently leaving in Spain.
  Cables are not really an option, I understand it would easier and cheaper, but it has to be wireless.

Nico.

[Reply #3 on:]

What is the distance between arduino/sensors  and   PC/display?
Is there much metal?

[Reply #4 on:]

distance sensors-display 10m max. Sensors-PC 5m max. Probably not much metal/carbon in between, let's say that if metal/carbon becomes a problem between sensor/lcd, I would do sensor-cable-wireless-lcd (so to bring the .  Forgot to say this, but one of the reason of going wireless is to have a portable display. Same goes if I have, let's say and android phone on deck, I'd like to be able to access the data (without cable).

Nico.

[Reply #5 on:]

Sounds like wifi is a good candidate. You can contact your PC and your android phone.
wifi shields are not cheapest and the libraries take quite some resources. Are you familiar with network programming?

Have you a complete list of sensors that will be on the Arduino?

[Reply #6 on:]

Are you familiar with network programming?

No, not at all... haven't seen much stuff on wifi-arduino, but loads of questions and queries around the forum...


Any idea on power comsumption of Wifi? My plan is to have the arduino on battery power, 1200mAh, need to last 3-4hrs.

Have you a complete list of sensors that will be on the Arduino?

Not complete yet. I have a gps (ls20031) and a 9DOF-razor (gets me boat angles). I'd start experimenting with those.

[Reply #7 on:]

Regarding power consumption - it relates to how busy the wifi chip will be.

As a point of example, a rig I have with a WiFly with a 3mA battery 100% uptime and a few sensors ... lasts just under 2 days. 
With it in a sleep mode for all but 30 seconds out of 5 minutes, the lifetime extends to weeks.

A link to more links:  http://arduino.cc/forum/index.php/topic,56724.0.html

Not certain if this fits your specific project needs directly though.  Are each of your sensors DIRECTLY connected to the Arduino, or are they remote from the Arduino?  Is your display separate from the sensor/data collection unit?

[Reply #8 on:]

Regarding power consumption - it relates to how busy the wifi chip will be.
As a point of example, a rig I have with a WiFly with a 3mA battery 100% uptime and a few sensors ... lasts just under 2 days. 
With it in a sleep mode for all but 30 seconds out of 5 minutes, the lifetime extends to weeks.

You meant a 3A battery right? Anyway it seems ok, LCD or GPS will consume more.

Current plan is for 2 sensor-boxes and 2 displays. Sensor-box would only send data, displays only receive it.

sensor-box1 and sensor-box2 which broadcast their data, sensor-box1 is currently a gps+9DOF+arduino+sdlogger, sensor-box2 is coming but not sure yet what it'll have. Both boxes will be fixed on the boat and battery powered.

display1 and display2 are portable; display1 will be a LCD+arduino+buttons (or 1'' 7d LEDS,x8 with a max7219), display2 is a computer (android mobile or pc). 

Thanks again for the help and comments.