Leonardo’s Lost Robots
By Mark Elling Rosheim
Springer 2006, 184 pp.

Dan Brown’s “The Da Vinci Code” opens with a gripping visual mystery: a corpse lying spread-eagle in grim reenactment of a famous Leonardo da Vinci drawing. If you don’t know why, then you are not among the millions who have seen the film or read the bestselling thriller. Leonardo’s iconic “Vitruvian Man” also graces the cover of Mark Elling Rosheim’s latest book—only this time it is a robot measured within the geometric proportions of the circle and square.

In “Leonardo’s Lost Robots,” Rosheim is on the trail of another intriguing da Vinci mystery: Did the renowned Renaissance painter, inventor, engineer and architect design some of the world’s earliest robots? And did he translate his designs into functioning machines? Rosheim seeks to answer these questions through an exhaustive study of Leonardo’s technical drawings, part of a corpus of 7,000 sketches dispersed in collections around the world. He situates this study in an examination of the work of Leonardo and his teachers and students and by exploring the late 15th-century fascination with all things mechanical. Rosheim then goes a step further by reconstructing three Leonardo models. In doing so, he hopes to demonstrate that the quintessential Renaissance man was indeed at the forefront of robotic technology.

Leonardo da Vinci’s technical drawings have long intrigued scholars. Elegant but fragmentary sketches suggest designs for a flying machine, a diver’s underwater suit and even a proto-automobile. Yet only in recent decades have certain sketches been identified as “automata”—the Renaissance term for programmable mechanical devices. Indeed, it is Carlo Pedretti, who in 1957 pieced together plans for a robotic knight, to whom Rosheim pays tribute throughout “Leonardo’s Lost Robots.” With the encouragement of this Italian scholar, Rosheim builds upon Pedretti’s work and that of other historians and art historians, and he does so from a technical angle. As a graduate of the University of Minnesota’s mechanical engineering department and head of his own robotic company, Rosheim is, as Pedretti writes in the introduction, “in the privileged position of turning to his fellow engineers of the past…and understanding immediately the workings of their minds.”

Rosheim writes this book as a journey of discovery—Leonardo’s, as well as his own. We learn of Leonardo’s early apprenticeship with a Florentine armorer, his study of ancient Roman mechanics and his commissions for mechanical spectacles. In a similar vein, we read of Rosheim’s determination to learn Italian, track down manuscripts, fit together fragmentary sketches and build models that accurately reflect Leonardo’s original plans. Though his interpretations may be contested, Rosheim believes that previous scholars have underestimated Leonardo’s technological sophistication. He identifies in Leonardo’s designs “a broader, richer tapestry with far more complex mechanisms than previously known.”

The three chapters that comprise the core of the book are each devoted to individual automata—a programmable cart, the robotic knight and a hydraulically powered “digital” clock. For Rosheim, these three machines represent Leonardo’s increasing skill with multiple subsystems, animatronics and digital logic elements—all of which prefigure current robotic technology. The account of these reconstructions is highly detailed. The author walks us through each step of determining a design and undertaking construction as he struggles with actuator valves, routing cables and driver pulleys. The color plates of manuscript sketches and Rosheim’s models and diagrams provide extensive accompanying illustration.

While the technical specificity of “Leonardo’s Lost Robots” may not appeal to everyone, Prism readers will surely appreciate Rosheim’s meticulous tinkering. For as Pedretti comments, Rosheim seeks not only to explain his interpretations but also to share the “exhilarating experience of establishing direct contact with one of the greatest minds that ever existed.” This book should appeal to readers interested in engineering history, robotics and mechanical engineering, and it should serve as a helpful resource in teaching early engineering. “Leonardo’s Lost Robots” offers a fascinating glimpse into the world of Renaissance technology and the genius of Leonardo da Vinci.

Robin Tatu is a freelance writer based in Washington, D.C.