alcohol sensor (and some patience)

Soldered the alcohol sensor into something that is connectable:

I tried to connect this to the Arduino, as I had the appropriate circuitry, but I did not get any legitimate output from it. 5V going in, 5V coming out with no variations. Nothing seems to be awry in wiring, as the circuit seems to be grounded properly (and the 5V current is flowing).

There are a couple of potential factors as to why I'm not seeing any results:

- I'm using a 10k ohm resistor, while some guides (and the datasheet for the sensor) asks for 100-200k. However, there seems to be a good amount of people using 10k and getting at least some kind of result. A batch of 100k ohm resistors I ordered is on its way, so I guess I can try with them when they come.

- This site claims that these sensors take 24-48 hours for its signals to be stable. It also tells me that I should not be powering the sensor directly from the Arduino, which I have been doing, out of concern that the power draw of the sensor might damage the board. I did receive the voltage regulator required for a secondary power source, but I'll also need a capacitor and a 9V battery connector, which are both on its way.

Let's hope I didn't get a dud and wait for the parts to arrive.

Comments

duty cycle testing

Now that I saw a physical response, I should try to make it similar to how a servo should be controlled. Servos are actuators that receive (expect) position input (as opposed to motors, which receive speed/intensity input). Simply put, it registers input as pulses, decoding the ratio of high (a "on" signal) to low in a given period as a position value. A better explanation : http://learn.adafruit.com/adafruits-raspberry-pi-lesson-8-using-a-servo-motor/servo-motors As I am waiting for my servo to be shipped, I will continue to work with the LED light. As opposed to my previous setup of having the light turn on every time the request is given, I will have the light turn on and off in a regular pattern until a request is given, upon which the pattern will change for one "cycle" (on-and-off pair). The on-and-off logic (previously the LED control logic) will be run in a separate thread: def dCycle(*args): global dCVal ...

dabbling with android

I've been wanting to dabble with Android development recently, and yesterday I realized that there is a Socket.IO client API available for Java/Android. The API is pretty straightforward, so I loaded a test Android project I had made for going through Android basics and connected to the OpenSesame Node server. and it works! I mean, the interface is non-existent and it's really just bare-bones, but having the servo respond through an Android application was pretty refreshing. (the web client and the android client "communicating" with each other--messaging is pretty much for debugging purposes)

playing with servos

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the quest for robots

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