Need Help Choosing Sensors for Arduino Projects

[d7x]

Hi,
I'm new to the world of Arduino and am looking to build a few introductory projects that simply involve reading values off of different kinds of sensors (temperature, humidity, pressure, sound, etc.) to display them on an LCD. I've seen individual sensors with wires that would plug directly into a breadboard and I've seen circuit boards that claim to measure the same attributes.

For example, when looking at temperature sensors, I see the DHT11, DS18B20, DHT22 and TMP36 that simply plug into a breadboard. But, I also see boards such as the BMP085 (granted, it does pressure + altitude as well) and the Sensiron Temperature/Humidity Sensor.

1) What is a smart way to choose between boards vs. sensors?
2) What is a smart way to choose the right sensor from several choices in those groups?
3) How do I know what' s compatible with the Arduino (other than looking for 5V)?

Thanks for your help

[adafruit_support_bill]

1) What is a smart way to choose between boards vs. sensors?

We put some sensors (like the BMP085) on 'breakout boards' because they come as surface-mount components which makes them difficult for experimentation. The breakout boards give you a little more room to solder on leads or header pins and make these tiny parts easier to work with. Sensors on breakout boards are no better - or worse than sensors in other packages.

2) What is a smart way to choose the right sensor from several choices in those groups?

* Look for one that works in the range of measurements you expect. For example, you will probably need a thermocouple if you want to measure oven temperatures.
* Look for one with the resolution and accuracy you need.
* Given more than one that meet those requirements, you can then consider:

• - form-factor (how well does it fit into your project)
  - ease of interfacing
  - cost

3) How do I know what' s compatible with the Arduino (other than looking for 5V)?

Most sensors can be adapted to the Arduino one way or another, but some need additional circuitry and/or interface code to work.
All the sensors in the Adafruit store are compatible with the Arduino. We generally supply the extra interface components when needed and most have libraries with example code.

[sheepdog]

Although the whole topic of 1-Wire is a little daunting at the outset, it really isn't so terrible once you get to know it.

And in the Arduino environment, we neatly skip over some of the more esoteric capabilities of the 1-Wire family.

To get good temperature readings, you only need a DS18B20, plus (perhaps!) a 4k7 resistor. (Probably as well to include it... won't do harm, MIGHT make a difference....

... and a little know how.

The following is couched in terms of a certain shield, but the shield, as far as this is concerned, is merely providing an easy way to connect to some basic pins. You don't need the shield to do everything in the tutorial.

http://sheepdogguides.com/arduino/ar3ne1tt.htm

(You won't even need to include the basic Arduino 1-Wire library to "play" with this.)