The Maillardet Automaton weighs about 250 pounds and is particularly distinguished by it's unusually large memory and excellent movements. The figure is kneeling at a writing desk mounted on top of a stand that contains the program and driving mechanisim. Information for the doll's movements is communicated up through the body by an intricate combination of levers, rods, pulleys and cams.

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The heart of the writing and drawing operation is actually a mechanical "read only memory" in the form of an array of disk cams rotating on a common shaft to drive the right hand of the figure. The cams are driven by a spring motor located at one end of the base that is coordinated with a second motor located at the other end. This motor is used to slide the stack of operating cams on their shaft into the proper position to produce the desired readout. The information contained in the undulations of the selected set of cams is picked up by three cam followers linked to the doll's hand to produce the required left and right, up and down, and vertical movements. There are seven programmed designs from which to choose. Two designs require four sets of three cams each and the remaining designs are each on three sets of cams. This adds up to a total of 96 operating cams to control the movements of the right hand. Additional, and far simpler, cams move the left hand, head and eyes of the doll.

It would be interesting to know exactly how the machine was programmed. One can specuate that the profiles of the cams were laid out after the doll was constructed by moving its hand over a master drawing and tracing the motions of the three cam followers on simultaneously rotating disks of brass which were then cut and filed to their proper shapes. Yet, this is only a guess as Maillardet's Automaton was built in an age in which trade secrets were kept closely within the circle of one's apprentices and family.