| 摘要 |
<p>In order to provide improved flexibility of operation consistent with small size, low mass and low inertia, a self-propelled drawing device 2 or 3 is driven by two independent wheels 12 whose axes are fixed, and has a writing tip 17 which marks the drawing medium 1 at a point which is not on the imaginary line joining the points of contact of the wheels with the drawing medium. In order to provide a simple umbilical cord which is less likely to impede the movement of the drawing device, the drawing device is connected to a stationary control device 5 by flexible conductors in the form of a ribbon 4 whose width lies in a vertical plane. Instead of a drawing device, the device can be arranged as a tracing device with counters on the wheels and a tracing tip instead of the writing tip. </p> |
