Mohammad » Uncategorized http://robotics.reefat.com Robotics Blog Wed, 17 Nov 2010 07:27:03 +0000 en hourly 1 http://wordpress.org/?v=3.2.1 My First Differential Drive Robot – ver.1 http://robotics.reefat.com/2008/09/my-first-differential-drive-robot-ver1/ http://robotics.reefat.com/2008/09/my-first-differential-drive-robot-ver1/#comments Tue, 16 Sep 2008 22:32:43 +0000 Mohammad http://robotics.reefat.com/?p=86 I think, I am running too fast. After building the ATmega motherboard, I didn’t take more than 1 day to build the whole robot. This was just for testing purpose (not even experimental; you can say pre-experimental). At this very moment, I didn’t have any mechanical tool to build up a nice-looking handsome robot. I just got a box came with my NiMH battery charger, and just convert it to the chassis of my very first robot. Here is a close shot of my ghetto bot:

The only task I assigned (programmed) to it was avoiding obstacle. Meaning, it can detect stuff ahead on its way, and avoids those roadblocks. Very simple, isn’t it? This is enough as the first program. I have some other plans to work with. And I will keep posting about my baby robot. So stay keep-in-touch and don’t forget to check the video:

]]> http://robotics.reefat.com/2008/09/my-first-differential-drive-robot-ver1/feed/ 1 Analog to Digital Converter Demo – Sensor Interfacing http://robotics.reefat.com/2008/08/analog-to-digital-converter-demo-sensor-interfacing/ http://robotics.reefat.com/2008/08/analog-to-digital-converter-demo-sensor-interfacing/#comments Fri, 22 Aug 2008 22:04:58 +0000 Mohammad http://robotics.reefat.com/?p=76 This is a simple demo for Analog to Digital Converter. Here I am using National Semiconductor ADC0804, which is a very common 8-bit A/D Converter, compatible with any 8-bit Microprocessor or Microcontroller. In this project I am using a CDS Photocell as an Analog Sensor which is the primary input for the ADC. Based on the input voltage on Pin 6, ADC converts it to digital signal which is an 8-Bit data between 0 and 255. This 8-bit data is then passed through these 8-lines and captured by the USBMicro Interfacing Device, which is plugged into my laptop. This USBMicro is very useful for I/O interfacing through the USB port.

Download VB.6 Source ADC-Demo-VB.6.zip
Download VB.NET Source ADC-Demo-VB.NET.zip

]]> http://robotics.reefat.com/2008/08/analog-to-digital-converter-demo-sensor-interfacing/feed/ 5 The First 8051 Microcontroller Project – LED Blinking http://robotics.reefat.com/2008/08/the-first-8051-microcontroller-project-led-blinking/ http://robotics.reefat.com/2008/08/the-first-8051-microcontroller-project-led-blinking/#comments Wed, 20 Aug 2008 21:22:18 +0000 Mohammad http://robotics.reefat.com/?p=44 The first “Hello World!” project I prefer for Microcontroller is LED Blinking. I have used ATMEL’s 89C51 (40-pins DIP) 8051 architecture microcontroller which is ideal for first time learning MCU Chip. I used my previously made 5V Regulator to supply uninterrupted regulated DC voltage. The program is very simple and straight forward, that uses a delay procedure that loops for 255 x 256 = 65536 times and produce loop based software delay.

		org		0000h
loop:
		mov		b, #0FFh
		acall		delay
		clr		p1.0
		mov		b, #0FFh
		acall		delay
		mov		p1, #0FFh

		ajmp		loop

delay:
		djnz		acc, delay
		mov		acc, #0FFh
		djnz		b, delay
		ret
end

]]> http://robotics.reefat.com/2008/08/the-first-8051-microcontroller-project-led-blinking/feed/ 14 Simple 5V Regulated Power Supply For Digital Circuits http://robotics.reefat.com/2008/08/simple-5v-regulated-power-supply-for-digital-circuits/ http://robotics.reefat.com/2008/08/simple-5v-regulated-power-supply-for-digital-circuits/#comments Wed, 20 Aug 2008 21:09:40 +0000 Mohammad http://robotics.reefat.com/?p=40 This circuit is a small +5V power supply, which is useful when experimenting with digital electronics. Small inexpensive wall adapter with variable output voltage are available from any electronics shop and supermarket. Those adapters are easily available, but usually their voltage regulation is very poor, which makes them not very usable for digital circuit experimenter unless a better regulation can be achieved in some way. The following circuit is the answer to the problem

This circuit can give +5V output at about 150 mA current, but it can be increased to 1A when good cooling is added to 7805 regulator chip. The circuit has over overload and thermal protection.

I have just made one which you see in the picture above where I have added two header pins so that it can be easily plugged onto a solderless breadboard.

]]> http://robotics.reefat.com/2008/08/simple-5v-regulated-power-supply-for-digital-circuits/feed/ 5 Rotary Camera Using Stepper Motor http://robotics.reefat.com/2008/08/rotary-camera-using-stepper-motor/ http://robotics.reefat.com/2008/08/rotary-camera-using-stepper-motor/#comments Thu, 14 Aug 2008 20:43:20 +0000 Mohammad http://robotics.reefat.com/?p=14 This is a simple stepper motor controller which rotates a small wireless camera attached to it. This uses the same circuit of the previous project. The only difference is that the camera moves only if the Right or Left arrow key is pressed from keyboard. In the previous project the stepper motor used to rotate anti-clock wise. Here I change the code little bit to rotate is clockwise. I just simple reversed the step sequence. So for clockwise rotation the step sequence is:

STEP-1   0001     5
STEP-2   1001     4
STEP-3   1000     6
STEP-4   1010     2
STEP-5   0010    10
STEP-6   0110     8
STEP-7   0100     9
STEP-8   0101     1

Here I used a wireless camera which sends A/V Signals at 2.4GHz frequency and on the other hand, the receiver receives it sends it to PC as video streams using an additional USB Capturing device named EasyCap.

The video capturing program is written in VB.NET using a 3rd Party Class names iCam which uses  avicap32.dll to work with the video captured by the camera.

Here is the live demonstration of this project:

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