Abstract: A freehand writing instrument will hold a writing tip. The instrument can draw the writing tip across a writing surface in one or more strokes. The instrument has a case sized to be handheld and has a longitudinal axis extending between a distal and proximal end of the case. Also included is a motor mounted at the case. The writing instrument also has an arm mounted at the proximal end of the case. The arm is driven by the motor to move periodically about a predetermined center, reaching a maximum transverse displacement from the center. With the distal end of the case defined as a vertex, this maximum transverse displacement is sized to subtend a displacement angle with respect to the longitudinal axis. The arm has a holder adapted to transversely hold the writing tip at an orientation displaced from parallel to the longitudinal axis no more than the displacement angle. The arm can produce a periodic pattern on the writing surface during the strokes.