What are “Tezuka-like” strokes?
The robotic arm, and how manga artists draw
Osamu Tezuka was able to express emotions such as joy and anger, grief and pleasure, in a single line by skillfully manipulating pen and ink. In the previous sections, we’ve already seen how amazing he was. In this project, we’ve tried to reproduce these lines of Osamu Tezuka’s using a robotic arm to express the characters.
It’s said that Osamu Tezuka’s lines were drawn with the pen angled quite close against the page. As you can see when you actually try it, it’s quite difficult for the pen to move vertically, and when you draw a horizontal line it becomes jagged. Osamu Tezuka showed exquisite control of the pen’s angle and pressure, and he drew his lines as required for the age range and the work involved. This sketch shows a plan devised to reproduce these lines. The pen is gripped by an articulated arm like a human finger, and the pressure is controlled by a pressure sensor. However, there is no modern technology that can simulate the delicate, complex movements of human beings, and the challenge of drawing the ideal line will continue into the future.
Reproducing the delicate strokes drawn by manga artists
The challenging trajectory faced by the robotic arm
The challenge of the robotic arm began with one question—was it possible to simulate the movements and pen pressure of Osamu Tezuka to draw? Here, we present the movements of the robotic arm that was created and the lines it drew.
As Mr. Mori has mentioned, in order to simulate the delicate movements of Osamu Tezuka, the mechanisms of human muscles must be reproduced in a robot. We sought to achieve this goal with our prototype robotic arm. However, we have not yet been able to achieve it to our satisfaction with the current technology.
This robot arm was created with the goal of improving the accuracy of these drawings, specialized for the function of drawing lines faithfully. We chose to use a felt-tip pen to keep the pen pressure constant. It’s now able to draw character outlines accurately. When actually drawing the protagonist of “PHAEDO” on paper, the AI successfully completed drawing the character with the support of the manga artists in charge of drawing.
In the development of any technology, the first step is crucial. Even if only a small step, it's undoubtedly a great step towards reproducing the pen-handling technique of Osamu Tezuka.