Archive for November, 2010

Oberon is a remote controlled robot for long range exploration

Oberon The Robot takes the ROV concept to an entirely new level, able to traverse just about any terrain and operate almost a mile away from the base station. Oberon also sends back color video, allows me to speak through the robot, and has an articulated head that can pan or tilt to survey the surrounding area. Being as tall as a person and having a helmet for a head, Oberon is not just an ROV, but also a humanoid actor, or robotic avatar that can be controlled from the comfort of my office chair.

A long range all terrain robot controlled via video link and remote control.

One of my very first robotics projects was a crude ROV (Remotely Operated Vehicle). This was really just a toy RC truck with a video camera and transmitter mounted to the top so that I could sit in front of a monitor and explore the backyard as if on some kind of deep space mission. Although this idea seemed pointless at first, the resulting ROV was a huge amount of fun to operate, and gave the sense that some vast alien landscape was being explored. The received video looked so different on the monitor than just walking around, and the little RC robot was good for the distance of the backyard and some of the laneway. I was now hooked on remotely operated vehicles.

 

A long range all terrain robot controlled via video link and remote control

Oberon takes the ROV concept to an entirely new level, able to traverse just about any terrain and operate almost a mile away from the base station. Oberon also sends back color video, allows me to speak through the robot, and has an articulated head that can pan or tilt to survey the surrounding area. Being as tall as a person and having a helmet for a head, Oberon is not just an ROV, but also a humanoid actor, or robotic avatar that can be controlled from the comfort of my office chair. The mechanics used to create Oberon are taken from a discarded electric wheelchair and mixed together with a welded frame, some standard RC parts and other components purchased from various sources. Building a robot like this is actually fairly inexpensive if you are good at salvaging junk and hacking things together.

 

<< More on this project: http://www.lucidscience.com/gal-showall.aspx >>

asp, audio, avr, counter measures, electronics basics, electronics projects, forum, gaming, high tech pranks, laser spy, lasers, remote control, robotics, software, spy gadgets, tasers, video

Advertisements
Figure 0 - This hidden device can intercept remote control signals and play them back!
This hidden device can intercept remote control signals and play them back!

This fun project lets you take control away from the person holding the remote control by intercepting the invisible signals as they travel through the air so you can play them back to the TV or video machine. You can also “train” your Remote Hijacker by recording certain button presses directly from the remote so that you can play them back later on, taking total control over the target appliance. Because this project records the remote control pulse stream directly, it will work on any infrared based remote control, able to learn a few button presses.

This project uses a very simple microcontroller program that just times the pulses coming into the infrared decoder and then stores them in the internal SRAM for later playback. The source code is made as simple as possible, allowing for plenty of room for modifications and alterations to suit your evil genius agenda. Because no interrupts are used, the C program could be ported to just about any microcontroller, and will work on all of the Atmel microcontrollers as is. Larger internal memory allows more button presses to be stored, with the Amtega88 (1K SRAM) allowing about three button presses to be recorded and played back.

Read more and see the videos: Build the REMOTE HIJACKER

Added : November 03, 2010

Generate VGA graphics using an AVR microcontroller
and an external frame buffer

Microcontrollers are well suited to display information on analog
VGA monitors

If you have been working on microcontroller projects for any length of time, then you know that it can be difficult to display a large amount of data, especially when it contains more than just plain text. There are limits to how much useful information you can display on a basic character LCD, or even a dot matrix LCD, since most have low resolution, no color, and a poor refresh rate. I came up against this problem when working on a robotics project that needed to display a color image captured from a small camera and decided to see how much effort it would take to create an image on a VGA monitor using only a microcontroller to “bit bang” all of the necessary signals.

It took some time to learn how the five signals used on an analog VGA connection made an image appear on the screen, but the end results were much better than anticipated, providing a crisp 256 by 240 image on the monitor in 256 colors. Although it does take some intensive cycle accurate assembly programming, the basic coding is not very difficult to understand once you have learned what the monitor expects. In fact, making a microcontroller drive a VGA monitor is much easier than creating a video signal for a television because the VGA monitor does all of the difficult color coding for you as long as you send the video signals and sync pulses at precisely the right time. “Precisely” is the key!

The final version completed on a solderless breadboard

Try desoldering the EASY way, using many of the tools used when welding!

make a VGA gaming system with any AVR

Generate VGA graphics using an AVR microcontroller and
an external frame buffer


Thanks to the cool folks at AVRFreaks.com forum for posting Brad’s VGA Video Generator in their tutorial section:  http://www.avrfreaks.net/index.php?name=PNphpBB2&file=viewtopic&t=99805

If you have been working on microcontroller projects for any length of time then you know that it can be difficult to display a large amount of data, especially when it contains more than just plain text. There are limits to how much useful information you can display on a basic character LCD, or even a dot matrix LCD, since most have low resolution, no color, and a poor refresh rate. I came up against this problem when working on a robotics project that needed to display a color image captured from a small camera and decided to see how much effort it would take to create an image on a VGA monitor using only a microcontroller to “bit bang” all of the necessary signals.

It took some time to learn how the 5 signals used on an analog VGA connection made an image appear on the screen, but the end results were much better than anticipated, providing a crisp 256 by 240 image on the monitor in 256 colors. Although it does take some intensive cycle accurate assembly programming, the basic coding is not very difficult to understand once you have learned what the monitor expects. In fact, making a microcontroller drive a VGA monitor is much easier than creating a video signal for a television because the VGA monitor does all of the difficult color coding for you as long as you send the video signals and sync pulses at precisely the right time. “Precisely” is the key!

This project is more like a tutorial, and is far from being perfect. The idea is to show how any microcontroller can be made to create a rock solid VGA image once timing parameters have been calculated properly. I am using an Atmel ATMega324 and ATMega644 for this project, but just about any microcontroller will work, once you understand the basics and decide on what type of image you want to display. This project will start off with a very minimal display system running from a single microcontroller and will progress up to a fully double buffered system that will display flicker free animations with a resolution of 256 by 240 and with 256 colors.

Any VGA monitor with a 15 pin analog connector will work, but the old-school glass CRT monitors will probably display the “nicest” image due to having round pixels and a truly analog horizontal line. Newer LCD monitors will work just fine, but there may be a slight “banding” effect on horizontal lines if you cannot adjust a setting called “pixel” clock. Nonetheless, the image will be very clean, crisp, and colorful on any VGA monitor.

I would like to thank the community on the AVRFreaks Forum for suggesting this tutorial and for all of the help that has been offered over the years by the many knowledgeable members. I hope this small project inspires those who want to generate video with a microcontroller and look forward to seeing what others can do to improve and modify these ideas!

The dissection of an older DVD player showing the useful parts that can be salvaged.

Broken DVD players contain many usable electronic and mechanical parts

As a mechanical and electronic appliance, a DVD player includes many useful parts for electronics and small robotics projects. Most DVD players have at least two motors, many gears and mechanical bits, a power supply circuit board and a large main board. Although modern manufacturing has reduced the size of the circuit boards on most every day appliances, using as many large scale semiconductors and surface mount components, it is still possible to salvage many of the larger through-hole mounted semiconductors for your own use.

Older electronic appliances usually have more salvageable components inside, but never pass up an opportunity to collect new, old, broken or working electronic devices for addition to your ever expanding junk pile.

Several circuit boards salvaged from an older DVD player


, , , , , , , , , , , , , , , ,

A DIY tutorial showing how to remove electronic components from a circuit board. 

Most of your parts inventory can be salvaged from old circuit boards

In order to build an electronic circuit from plans or from scratch, you will need a number of semiconductors and components. Often, these individual components cost only pennies new, but in order to purchase from a large supplier there will be a minimum order number or price level that has to be met. It would seem crazy to pay $25 in shipping to receive a few 10 cent capacitors or resistors, especially when you can salvage them from just about any old circuit board. Almost all of the components I use are salvaged from old boards. I don’t think I have ever had to order an odd value resistor or capacitor as I have always found what I needed by scavenging my huge junk pile.

A few dead TV or VCR circuit boards will net you enough raw components to fill an entire electronics parts bin, and allow you to experiment with varying values as you breadboard a new or published circuit from a schematic. Almost any discarded appliance that includes a power cord will become a great source of raw semiconductors, so tell everyone you know not to throw out their broken appliances, send them to your mad scientist lab for dissection!

, , , , , , , , , , , , , , ,