From Biology to Systems Engineering and Electronic Design
- Members: Andy M. Tyrrell, Julian F. Miller, Martin A. Trefzer, Tuze Kuyucu
- Funded by: EPSRC - EP/E028381/1
- Dates: July 2007 - July 2010
Natural Development as an Inspiration for Electronic Design
The development of multicellular organisms from a single cell (zygote) is one of the most amazing mechanisms in biology. Without development, the complex multicellular organisms, such as humans, animals and plants, would not exist. Whilst a single cell is a highly complex entity in itself, unicellular organisms are still vastly limited in the tasks they can achieve and are vulnerable to environmental threats. A multicellular organism, however, is capable of multi-tasking using division of labour amongst the cells, and is able to protect itself from environmental threats better than a unicellular organism would since the loss of a cell or few cells does not necessarily harm the organism as a whole. Hence, multicellularity is key to achieving complex and intelligent organisms capable of executing sophisticated behaviours and surviving harsh and changing environmental conditions.
In biology, development is used to create a fully functional adult organism from a highly compressed piece of information-the genotype of an organism(i.e. the DNA)-that is stored within a single cell. Furthermore, development is also a mechanism that maintains the stability and functionality of an organism throughout its lifetime, and not merely a genotype-phenotype encoding mechanism in biology for creating complex multicellular organisms. Thanks to multicellular development an organism is capable of surviving damage and loss of its physical parts, which otherwise would be lethal to the organism.
Artificial Development and Unconstrained Evolution in Electronic Design
This project aims to create an artificial developmental system (ADS), which is capable of growing higher-level adaptable entities without human intervention. An unconstrained evolutionary algorithm (EA) is used to evolve the genetic code of a zygote (stem cell), which is then capable of growing into a multicellular organism. As the organism grows, cells specialise in performing particular tasks depending on their environment and thereby form "organs". Speaking in terms of hardware systems, a cell is represented by a configurable circuit unit that can perform various simple tasks. These circuit units can connect to each other and form sub-circuits (organs), and the sub-circuits are part of the organism (hardware system).
Unlike in hardware evolution experiments, where the configuration of a hardware substrate is directly evolved, a circuit building instruction set (similar to DNA) is evolved in the case of hardware development. The single instructions are called genes. Genes interact with each other through proteins, which can be considered as "actions" or "messages": a gene can activate/inhibit other genes, communicate with the environment or modify the underlying circuit structure. The complexity of interactions increases with the number of genes. As a consequence, in order to translate the "DNA" into a working and adaptive hardware system, a mechanism that is able to process this gene regulatory network (GRN) is being developed in this project.
Investigating Self-Repair and Adaptation
While "growth" can be viewed as a self-specifying decompressing process from genotype to phenotype (building an entire system from a compressed instruction set), it also allows another important property: self-repair. As in biological systems, the ability to (re-)grow is the key feature to be able to replace faulty or damaged parts. A stable developmental process should therefore be able to recover from errors and adapt to environmental changes even if it is not explicitly evolved for such behaviour. Such phenomena will be investigated in this project. This will have enormous ramifications on the production of future systems; reliability and fault tolerance of systems may be greatly improved under uncertain environmental conditions.
Links
Martin A. Trefzer, personal page.