Show Posts
Pages: [1]
1  Community / Exhibition / Gallery / Arduino Remote Controlled Mouse and Keyboard on: March 22, 2012, 04:42:51 am
Hey guys,
Some time back I'd done a small hack using an Arduino to control mouse and keyboard from an IR Remote. The source code along with some more info is now up on my blog here:

Hope it helps.


2  Using Arduino / Sensors / Re: Weird analog IR sensor behaviour with different power sources on: June 16, 2011, 08:36:00 am
Hey I finally solved the issue. The problem indeed was due to voltage ripples from the eliminator. I added a 100uf capacitor(between Vin and Gnd) and a 0.1uF capacitor(between Vout and Gnd) to my 7805 circuit and voila! The sensor readings became much more stable, even lesser fluctuating than those in the table! The 100 uF cap smooths out the bigger ripples, while the 0.1 uF cap smooths out the high frequency ripples after the 7805.
3  Using Arduino / Sensors / Weird analog IR sensor behaviour with different power sources on: June 15, 2011, 11:13:56 am
Hi guys, I'm building a line follower. I've used 5 analog IR sensors. I get high values on a black surface and low values on white. I'm facing some trouble with analog IR sensors while using different power supplies. Here's a screen shot of actual sensor data(picture attached):

These are the readings obtained from the sensors with different power supplies. These sensor readings were taken keeping the line follower at a fixed position over the line. I suspect the unusual sensor readings for the second case is due to irregular voltage spikes. Can somebody please suggest a solution? Any rectifier circuit that I need to add? I wish to use both batteries as well as the battery eliminator for providing power(not simultaneously).

I've used a 7805 power regulator with two 10uF 63V capacitors for regulated 5V supply. One capacitor is connected between 7805's input and Gnd, and other is connected between 7805's output and Gnd.

Here's a description of analog IR sensor, commonly used in line following applications.
They give an analog output depending upon how much black or white surface they see. S1 to S5 are the readings of 5 sensors I'm using in my bot. Line is the weighted mean of the 5 sensor readings(this column may be ignored). I'm not using the pololu ones, but a similar circuit with tweaked resistances and locally available IR sensor and emitter. When a sensor is over a black surface, it gives high values and when on white, gives low values. I connected the sensors to analog inputs of a arduino, which interprets the sensor input in the range 0 to 1000.
4  Using Arduino / Motors, Mechanics, and Power / Re: L293D motor driver circuit problem on: June 15, 2011, 11:00:44 am
Actually I was making a silly error. The batteries I was using didn't have enough juice to power the motors. I replaced them with higher mAh batteries and now they work fine. Thanks!
5  Using Arduino / Motors, Mechanics, and Power / Re: L293D motor driver circuit problem on: June 13, 2011, 06:25:36 pm
I'd not used independent power sources the last time though while controlling the bigger dc motors..

Please help! smiley-sad
6  Using Arduino / Motors, Mechanics, and Power / L293D motor driver circuit problem on: June 13, 2011, 06:10:21 pm
Hi! I'm trying to control two small DC motors. They are similar to these motors ( but are of local make. I've a L293D H Bridge circuit to control it. I've also a voltage regulator circuit that uses a LM7805 voltage regulator for regulated 5V source. Power supply is from a 12V 2A wall adapter. The Vs pin(pin smiley-cool of the L293D is connected to positive of the unregulated power supply and rest of the L293D circuit is usual. I want to achieve motor direction control using Arduino. I'd read at some tutorials that it is a good idea to use separate power sources for Arduino board and motors. So I power the Arduino from a separate 9V battery.

I'm facing a weird problem. When I'm supplying 5V and Gnd to the input pins of the L293D directly from the voltage regulator circuit, the motor is rotating normally and reversing direction on reversing the input. But in this state, the moment I connect the ground of Arduino(powered on) to L293D circuit, the motor stops rotating. Any ideas on how to resolve this issue? I'd used the same circuit and setup with common grounding before, on a different pair of bigger DC motors than these ones and hadn't faced such a problem.
7  Using Arduino / Motors, Mechanics, and Power / Re: H Bridge on: June 13, 2011, 04:59:50 pm
In fact, as long as you don't intend to use pwm for motor control, you can simply connect both enable pins to +5V and forget about setting them high with digitalWrite().
8  Using Arduino / Motors, Mechanics, and Power / Re: H Bridge on: June 13, 2011, 04:56:59 pm
The code for you've written doesn't seem like it would change directions of the motors based on val>50. To change direction, you need to change loop() to:
void loop()
int val = analogRead(ldrPin);
Serial.println( val );

The above code would reverse motors depending on value of val.
9  General Category / General Discussion / Re: newbie help on: June 09, 2011, 03:44:24 am
Welcome to the amazing world of Arduino!

A very well written on-line Arduino tutorial:

This page has some info about good books written on Arduino:

I'd also highly recommend this book as a complete Arduino reference:

Hope this helps smiley
10  General Category / General Discussion / Re: Add Arduino hex File into Proteus ISIS on: June 09, 2011, 03:35:36 am
Yes, it's possible to simulate Arduino code using ISIS.
Here's a very simple tutorial I found:
I've not tried out any really complex sketches yet. But I guess it should work like a charm.

When you click on upload, the hex file is created in the Temp folder by the Arduino IDE. To find the hex file in Windows XP, goto to this location: C:\Documents and Settings\<user-name>\Local Settings\
and just search for *.hex. Make sure you select "Search hidden files and folders" check box.

Here's an old forum thread discussing the same:

Hope this helps!  smiley-wink
Pages: [1]