Evolvable hardware (EHW) is based on the idea of combining a reconfigurable hardware device with genetic algorithms to execute reconfiguration autonomously. FPGA (Field Programmable Gate Array) and PLD (Programmable Logic Devices) are typical examples of reconfigurable hardware devices, for which there is already a market worth more than USD2 Billion US dollars and growing at 23 per cent per year. An example of EHW is NASA's Space Technology 5 nanosatellites, which are scheduled to start measuring Earth's magnetosphere in late 2004. They were designed by NASA engineers using genetic algorithms and 32 Linux PCs. The computers generated small antenna-constructing programs (the genotypes) and executed them to produce designs (the phenotypes). If deployed it will be the first piece of evolved hardware ever to be launched into space.

Evolvable hardware (EHW) refers to hardware whose architecture/structure and functions change dynamically and autonomously in order to improve its performance in carrying out tasks. The only single resource presenting both the fundamentals, and the latest advances in the field, this book teaches the basics of reconfigurable devices, why they are necessary and how they are designed.

On behalf of the ICES 2001 Conference Committee, it is our pleasure to present to you the proceedings of the fourth International Conference on Evolvable S- tems: From Biology to Hardware, ICES 2001, held in Tokyo, Japan, on 3-5 - tober 2001, addressing the latest developments and discussing challenges facing the ?eld of evolvable systems. The idea of evolving machines, whose origins can be traced back to the - bernetics movement of the 1940s and the 1950s, has recently re-emerged in the form of the nascent ?eld of bio-inspired systems and evolvable hardware. Foll- ing the workshop, Towards Evolvable Hardware, which took place in Lausanne, Switzerland, in October 1995, the First International Conference on Evolvable Systems: From Biology to Hardware (ICES96), was held at the Electrotech- cal Laboratory (MITI), Tsukuba, Japan, in October 1996. The second and the third International Conferences on Evolvable Systems: From Biology to Ha- ware (ICES98 and ICES 2000) were respectively held in Lausanne in September 1998, and in Edinburgh in April 2000. Following the success of these past events, ICES 2001 was dedicated to the promotion and advancement of all aspects of evolvable systems, including ha- ware, software, algorithms, and applications. By bringing together researchers who use biologically inspired concepts to implement real systems in arti?cial - telligence, arti?cial life, robotics, VLSI design, and related domains, ICES 2001 reunited this burgeoning community.

This book constitutes the strictly refereed post-conference proceedings recording the scientific progress achieved at the First International Conference on Evolvable Systems: From Biology to Hardware, ICES'96, held in Tsukuba, Japan, in October 1996.
The volume presents 33 revised full papers including several invited contributions surveying the state of the art in this emerging area of research and development. The volume is divided into topical sections on evolware, cellular systems, engineering applications of evolvable hardware systems, evolutionary robotics, innovative architectures, evolvable systems, evolvable hardware, and genetic programming.