Digital LOGO

In 1975 Dr Harvey Cohen introduced a screen version of LOGO -- variously called WHAM and TINMAN, where the screen robot -- called a NAKI, could turn only through 90 degrees, and roamed a 16x16 grid. athe system, called OZNAKI, Polish for "logo" or "sign", was implemented on the earliest microcomputers, using as screen robot what was called a NAKI, which had the screen form ASCI characters     ^ , > , V , <     but for later implementations graphic characters were used:

NAKI heading UP     NAKI heading EAST     NAKI heading DOWN or  SOUTH     NAKI heading WEST

Earlier, in 1974, whilst Cohen was a Consultant to the LOGO Group within the MIT Artificial Intelligence Laboratory, he, together with Andrée Beaulieu-Green, had argued for the inclusion in "Standard LOGO", of a JUMP HOME command, which would return the screen Turtle to its home position, while retaining the Turtle's heading. (Retention of the Heading was so that the Abelson-di Sessa Turtle Round Trip Theorem would still hold.) Thus was implemented in OZNAKI by the J command. Here are two simple examples of OZNAKI programming:
Four-fold figure using J cmd OZNAKI squiral
Four-fold figure drawn using the J command -- which sends the NAKI back home while retaining heading. On each iteration W=VJ draws one arm of the figure and jumps home with heading altered by 90 degrees. So 4W draws the complete figure. Squiral drawn iteratively on the command 10X! Note that the contents of the Accumulator is denoted by A, the command + increases A by 1, - decreases A by one, while, for instance, command string 5+! increases A by 5. A is set to zero by the command A-!

1976-77 OZNAKI. Microcomputer Wizard's Box, was a Poly-88 8-bit microcomputer, supplemented with a North Star floppy disc. The specialised keyboard inspired by Perlman's Button Boxes.
The NAKI was not capable of precise drawing, but was driven by students around obstacles enhancing their understanding of the meaning of R and L commands, so enhancing spatial projection capabilities.
TORTIS Button Box Turtle and 2 kids
1974 LOGO Turtle with TORTIS Button Box.
The Turtle was rather sophisticated, using digital stepper motors, and could draw fairly precisely, using the centrally mounted pen.
However in this image the Teddy Bear design was achieved by the instructor.

To recapitulate, in the earliest screen versions of OZNAKI, the NAKI had the screen form ^ , > , V , < but for later implementations graphic characters were used:

NAKI heading UP     NAKI heading EAST     NAKI heading DOWN or  SOUTH     NAKI heading WEST

These same graphic characters were used in the LOGO on a 2K ROM, OZ-LOGO marketed for the Australian 8-bit microcomputer, the MicroBee, which was marketed world-wide 1983-1989.
In the first versions,the NAKI's trail was marked with an asterisk *. However in later versions, and in OZLOGO for the MicroBee, the trail was marked by a (16x16) graphic character. Conversely the pattern of marked cells could serve to define a new graphic character. ( Following the command U inherited from LOGO, no trail was left, and trail-marking resumed with a D.

OZLOGO NAKI exploded 16x16

OZLOGO NAKI drawn with trail of the NAKI body
Visual recursion was a feature of OZLOGO

OZNAKI and Cubetto
The Cubetto Playset manufactured by PRIMO Toys is
"The coding toy for girls and boys aged three and up"
Basic commands for the motion of the Cubetto robot are effected by plugging into the control box coloured pieces:
RED = Left       YELLOW = Right       Green = Forward
while BLUE block runs the sequence in the bottom row.

Cubetto provides planboards -- about which the small cubic Turtle can roam. Grid size matches the distance of the robots forward step, so if initially centred and oriented the robot will move from the centre of one square to another. These planboards are termed by PRIMO "education maps" and are supplemented with motivational stories, related to specially marked squares.
Cubetto was conceived as for the kindergarden child. It provides basic programing experience without the use of a screen.

Towards an Advanced Cubetto
But what next ? Surely a screen system with similar features, screen Turtle that turns only through 90 degrees, navigating a square region that is a chess-board like matrix of squares. Butwith some squares excluded -- others offering Easter Eggs. A bigger system would offer a choice not-only of region maps -- but greater programming capability. Maybe the advanced user could program a simple PACMAN.

Thus OZ-LOGO can be viewed as the proto-type for the advanced screen-based Cubetto

Click to return to home page for the OZNAKI Project

Papers about OZNAKi, the languages, evaluation in terms of achievement of cognitive goals, and technical aspects of its implementation can be found here