English   Robotics

(Prologue: Prof. Maria Cristina Moreno)

In science fiction books, the writer, like an alchemist, gives life to robots that today find themselves in our daily lives; from a simple coffee-maker, to the Mars Rover.

The objective is that technology and education, together, show the way towards the future.
The proposal is that at home and at school we can make and handle simple robots.

With these premises, Marcelo Duschkin presents the project Mi Primer Robot, based on a simple and economic electronic interface, TortuRob, that we can make freely (Creative Commons License).

Chosen software to command the robot from a PC is Xlogo, a modern version of the traditional Logo created by Seymour Papert at MIT, in the 70's.
XLogo is free software, published with the GPL license, and works on Linux, Mac and Windows.

Why XLogo?

  • Free software (GPL License).
  • Writen in Java, it is multiplatform, that is to say, it is within reach of a greater number of people.
  • Multiple languages supported.
In November 2006 the first version of XLogo appeared (as patches) to command an external interface for robotics, in the "Cafeconf - Aulas Libres" congress.

At the moment, XLogo officially incorporates several primitives for network communication, being used for the experimentation in robotics, as well as network group tasks, chat, and allows control of the turtle PC from another PC.

Robot

Picture: Marco Antonio de Hoyos

The electronics:

TortuRob is an electronic interface project.
It is a circuit based on a PIC16F628A microprocessor, that receives commands from the PC, and contains ports for input and output to control the robot's mechanics.

Four switches and four LEDs are also included, with the intention of using them to learn to use the system. This way, the first tests do not need the robot mechanics to be controlled.

The board is of small size (9.5 by 7 cm) and is very easy to build by the electronic's fan.


board

The mechanics:

In Mi Primer Robot site, at "constructive details" link, you can see models of robots builds with motorized toys or construction blocks.

Educative aspect:

The objective of this project is to promote interest in the study and local application of technology.
The use of free tools and an attitude to share knowledge, is a key message for new generations.

Seymour Papert, Logo creator said:
"If any ability that a boy learns is obsolete before he uses it, then, what it is he must learn?
The answer is obvious: The only competitive ability in the long term is the ability to learn".

From the Didactics, the displacement that obtains the turtle is fundamental, so that the student can be located nonsingle in the space plane but also to understand the concept of coordinates using graphics and colors.
With Logo, the student teaches to the turtle. This way, their roll is active and creative.

Logo allows the student to solve complex problems, by separating it into several smaller simple problems.

Technical details:

XLogo uses Ethernet to communicate with the 'outer world'.
As the TortuRob interface uses a serial connection (RS232), an intermediate conversion is necessary. In Linux it is easy (obvious) and in fact this conversion is implemented by software with a simple Tcl/Tk script that runs along with XLogo. This option is adapted for individual PCs.

The conversion can also be made by a hardware control module external to the PC, and this option is recommended to be used in a classroom with several PCs in a local network. This way, the interface and the robot are connected to the teacher's PC, but any student can command the robot from their PC.

This flexibility allows the system to be used with other interfaces, like the Spanish Enconor, or with an own design, or a modified TortuRob.
The communication protocol is depicted in Mi Primer Robot site.

All ready to use:

All necessary software for our laboratory of educative robotics is free software, and therefore it's available to download and to install. But this can be difficult for a young beginner who is impatient to 'put hands to the work'.

Thus the idea was born to create RoboTux, a live-CD based on Puppy Linux, a fantastic Linux mini-distro, able to work in PCs of limited resources.
RoboTux already brings installed XLogo, Java interpreter (SUN JRE 1,5) necessary for its execution, the serial terminal CuteCom (for hardware tests) and a Tcl/Tk script to turn Ethernet < - > RS232 by software.

Of course, also included is all the documentation (manual and examples) so that everything works without complications.

As Puppy is not available in Spanish, the project includes to obtain (in the future) the possible most complete translation of all the other typical applications included (navigator, mail, chat, publishers, etc).

An .iso image of the first beta of RoboTux can be downloaded from:
http://descargarlinux.com.ar/culturalibre/robotux-b1.iso

Information of how to create a booteable CD from the .iso image can be seen in:
http://www.espaciolinux.com/artitecid-48.html

Contact and Mail List to share experiences:

You can contact me at mardus@gmail.com for any consultation on the subject.
Also there is a mail list in Spanish specific to the use of XLogo in educative robotics. You can participate by subscribing to:
http://ar.groups.yahoo.com/group/xlogo-es