Home of www.RoboHobby.com Java robotics project www.CubesAndCrosses.com
Train your logic skills in geometry
Create and delete one-color crosses
Play for free right in your browser!
Home-made CNC machine
Our new project -
How to make home-made CNC router
PICkit2 - Tutorials, Experiments
PICkit 2 - Small size USB programmer
from Microchip.
How to use it as a demo device for
USB programming in C language

www.RoboHobby.com
Home of www.RoboHobby.com
Java robotics project


Portable Notebook Table
How to make Portable Notebook Table.
Do it yourself!

Control robot on-line (GWT)
Control our robot on-line,
using GWT-based Web interface

Web-based (GWT) remote control for Java robotics.

Control robot on-line
Control our robot on-line,
using simple Web interface
(Old JSP-based version)

Web-based (JSP) remote control for Java robotics.

Sun SPOTs for robotics
Sun SPOT for hobby robotics.
How to use Sun SPOT devices
comunication of group of robots


Sun SPOT Accelerometer + Servo
Sun SPOT Balancing robot
Draft of new article


PICkit2 - Tutorials, Experiments
PICkit 2 - Small size USB programmer
from Microchip.
How to use it as a demo device for
USB programming in C language


Java SE SWING JSR-296 Example
How to run background task in
JSR-296 SWING application
with 'busy animation' in the status bar.
Useful addition to Netbeans template.

Java ME Code Examples
Java ME Source code examples
for robotics projects


Run Java ME Code Examples
How to run our Java ME code examples
for robotics projects


Java - work from home
Draft for article
'Java work from home.
(Java and self-employment)
Where and how to get
remote (telecommuting) job'


ScreenShots
See some screenshots of RoboHobby
Java/SWING application

See some screenshots of www.RoboHobby.com Java SWING application

Where programmers go
after age of 35?

Article in Russian
about job discriminationin
in IT industry:
'Where programmers go
after age of 35'?




Atmel NGW100 for
Java Hobby robotics

Set of articles about
Atmel NGW100 for
Java Hobby Robotics




Canon A570 IS + CHDK for
Kite Aerial Photography

How to use photo camera Canon A570 IS
with CHDK for kite aerial photography

Plastic box for Canon A570 IS
for Kite Aerial Photography (KAP)

How to make plastic box for Canon A570 IS

Kite Aerial Photography
Create your own hand-made kite for KAP
and do snapshots from a kite

Create your own hand-made kite for Kite Aerial Photography (KAP) and do snapshots from a kite, using cell phone or camera.

RoboHobby Kite
How to install and use
J2ME program on your cell phone,
make spy camera from it
and do snapshots from a kite

Picavet Suspension
Hand-made 'Picavet Suspension' for
Kite Aerial Photography (KAP).
How to make it by yourself.

Compact Picavet Suspension
Aluminum Home-made compact
'Picavet Suspension' for
Kite Aerial Photography (KAP).
You can fold it and make it
portable.

How to fly 'Flow form' kite in calm (No Wind) condiction.
Green Island KAP photos
Photo views from kite of
'Green Island'

Green Island
Some views from the ground
of rectreation zone
'Green Island'

KAP Wind Maps
Web-Map-based project
for local win measurement



Simple Spam Protection
Simple Spam Email Protection -
GWT-based code example


Under Linux
Install and Run RoboHobby application under
KNOPPIX 5.0


Under Windows
Install and Run RoboHobby application under
MS Windows XP


Platforms for Java Robotics
Which hardware/os platform to choose
for hobby robotics?



Download
Download RoboHoby Software

SpyGear's 'Spy Robot'
Article about reconstruction RC toy 'Spy Robot'
How to make robot with web camera or
with cell phone on a board from it


Load to your phone
Download RoboHobbyJ2ME application
right to your Siemens S75 cell phone.
Now no need to load it to PC, unzip, etc.


RoboHobby Linux Live CD
RoboHobby Linux Live CD
is ready for download.


Projects
List of old and current RoboHobby projects.

Hardware
List of what we use as a hardware

Software
List of software, we use in our projects

Computer vision
Vision is the main sense of our robots.
See some Java algorithms we use

Tips-n-Tricks
Some advices about hardware and software tricks

PIC Programming
(firmware)

Assembler program for PIC16F628A
Communication program for sending
commands from cell phone to motors.
Driver for motor controller.


RoboHobbyPlugin
Open Source project on
SourceForge, Java brain
for the robot

How to update Java
on KNOPPIX 5.0

Set of articles about how to remove
old version of Java (JRE or JDK)
on KNOPPIX and install new one
on remastered CD
Part 1 (Just test new Java)

Part 2
(Place new Java on Linux Live CD)



Java to EXE
Article about how to compile Java
programs to native binary code
(EXE for Windows)


Range of Bluetooth, Wi-Fi, ZigBee
What is the a real connection distance
of typical Bluetooth and Wi-Fi,
ZigBee or other RF devices?



What is inside?

What is inside web camera
'Genius Look 312P'?
How to re-construct it,
improve and use in robotics.

What is inside web camera
'Genius VideoCAM GE111'?
How to re-construct it,
improve and use in robotics.

What is inside web/photo camera
'Genius G-Shot D612'?
How to use it for
Kite Aerial Photography (KAP).


Sun SPOTs (in Russian)
Sun SPOT for hobby robotics.
Introduction lecture in Russian.




About
Some info about this site

About EATJ Java hosting
Some info about EATJ Java server-side
JSP/Servlet hosting



Short description of www.RoboHobby.com in German In German
Short description of www.RoboHobby.com
in German


Short description of www.RoboHobby.com in French In French
Short description of www.RoboHobby.com
in French


Short description of www.RoboHobby.com in Spanish In Spanish
Short description of www.RoboHobby.com
in Spanish


Short description of www.RoboHobby.com in Italian In Italian
Short description of www.RoboHobby.com
in Italian


Short description of www.RoboHobby.com in Russian In Russian
Short description of www.RoboHobby.com
in Russian





www.RoboHobby.com


What is the real connection distance of typical Bluetooth, Wi-Fi and ZigBee devices?


It is always interesting to know what is the real range of radio connection between Bluetooth or Wi-Fi devices.
Usually you can find only some limited technical information in specifications and datasheets.
You can find some digits in decibels, but what this means to you?
What distance in meters will be OK for the normal connection in real environment?
Is the range is suitable for hobby robotics?

To check this we decided to do some tests with real devices on the real fields.
We had in our hands:

1) BlueTooth USB adapter Tekram TM-306 (Class 1, 100 meters range)
www.RoboHobby.com outdoor tests of BlueTooth adapter Tekram_TM-306.
www.RoboHobby.com outdoor tests of BlueTooth adapter Tekram_TM-306. Details.


2) BlueTooth USB adapter BlueTake BT007Si
www.RoboHobby.com outdoor tests of BlueTooth adapter BlueTake BT007Si.
www.RoboHobby.com outdoor tests of BlueTooth adapter BlueTake BT007Si. Details.

3) PDA HP IPAQ HX2790 (it has BlueTooth and Wi-Fi too)
4) Notebook 'Samsung R40'
5) Cell phone Siemens S75 (it has BlueTooth on board)

Important note: We do NOT used any antennas. Our goal was to test BlueTooth and Wi-Fi connections,
using the devices 'as is', without any kind of antennas.
We did tests on the field, on the empty territory with some bushes and trees.


The territory, where we did our outdoor tests of BlueTooth and Wi-Fi connections looks like this:

Place where we did our outdoor tests of BlueTooth and Wi-Fi connections.
Place where we did our outdoor tests of BlueTooth and Wi-Fi connections.

The results of the BlueTooth tests:

Test 1:

BlueTooth connection between notebook with Tekram TM-306 and PDA.

During the test PDA should transfer big file via BlueTooth to notebook.

The range of this connection was just 16 meters.

There is one interesting fact - when you put notebook right on the ground the range reduced.
It may be something about 10-12 meters.
But when you raise it up in your hands, for example 1.5 meters from the ground level, the connection distance may become 14-16 meters.


Test 2:

BlueTooth connection between notebook with Tekram TM-306 and cell phone Siemens S75.
The range of this connection was just 14 meters.

As I suppose, BlueTooth receiver of Siemens S75 in not so good as BT adapter in HP IPAQ HX2790.


Test 3:

W-Fi connection between notebook and PDA.

During notebook sent pings to PDA.

The range of this connection was not so bad - 132 meters!

Again - when you put notebook right on the ground the range reduced, when you raise it up in your hands, distance becomes much longer, then right from the ground.
Test 4:

Why connection between two BlueTooth devices is so short (16 meters)?
We had an idea to do one more test - connect two Class 1 BlueTooth adapters.
May be if we have Class 1 adapters (100 meters) on the both sides, things will be better?

We placed one Class 1 Bluetooth dongle was connected to desktop PC, another was connected to notebook.

The range of this connection was 50 meters.
(Much better then 16 meters in the first test)!

Distance of ZigBee (Sun SPOT from SUN Microsystems)

Connection distance (range) of ZigBee (Sun SPOT from SUN Microsystems)
Recently we have teased one more type of small devices - Sun SPOT from Sun Labs.
In official documentation it is declared that range is 10-75 meters.

In reality after some tests we have found that real measured range in a building is about 8 meters.
Range in free air is about 20-25 meters.

But we should keep in mind, that Sun SPOTs can
work as a ZigBee-network devices and they can translate traffic to next device.
Using this feature you can create 'digital district' - small or big field (or building),
where you can place a lot of such a devices and
they can translate traffic and even calculate the best way for packets.
That means - if you have only two devices, it can work together and see
each other in a rang of 25 meters.

But (!) if you have 3 devices, they can cover distance of 50 meters,
4 devices can cover 75 meters, etc.

Sun SPOT - internal mini antenna.
See some info about Sun SPOTs:
Sun SPOTs for robotics

TO BE CONTINUED...

Next topics:

How to create hand-made Bluetooth and/or Wi-Fi antenna, using very simple materials and details.

Also it would be good to do test on the field radio frequency chips from Microchip and Atmel.
There are some RF Microchip chips, which have RF transmitters and receivers.
The chips are: rfRXD0420 Receiver Module, ZigBee RF Transceiver MRF24J40, etc.

It would be good to test their real connection range.









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