Self-healing Cellular Architectures for Biologically-inspired Highly Reliable Electronic Systems

强大而复杂的系统，从计算机到控制系统，再到“传统”家用电器，已经成为我们现代生活方式的必需品。在数字电子的现代世界里——几乎所有的电子产品都是用超大规模集成电路技术制造的——我们已经习惯了这样一种想法，即一个芯片上成千上万、甚至上百万个单独的组件必须在很长一段时间内完美地工作。然而，它通常只需要一个晶体管失败，对整个系统造成灾难性的后果。想象一辆汽车在繁忙的高速公路的快车道上高速行驶。突然，电子发动机管理单元（EMU）出现故障，发动机熄火；不久之后，伺服辅助刹车和转向（这取决于发动机进气歧管真空）都停止正常运作；一队停着不动的车辆正迅速驶来。这种情况的结果留给读者想象。这是一个有点戏剧性的思想实验，但它将我们生活中一些日常数字电子元件的安全临界性和可靠性方面带入了一个鲜明的焦点。设计复杂但可靠的电子系统并确保其长期无故障运行是我们今天面临的主要挑战。这种需求在电子系统的情况下更加明显，其中其正确操作是必不可少的，例如，防抱死制动系统，电传飞机，空间探索，工业控制和停机系统；它们应该能够在出现故障的情况下正确操作，并且具有容错性。我们怎样才能设计出如此可靠的系统？自然界提供了一些处理复杂性和不可靠性的杰出例子。生物体，特别是人体，是已知的最复杂的系统之一。然而，它们具有极高的可靠性。虽然由于有害病原体和环境条件造成的局部故障是常见的，但生物体的整体功能是高度可靠的。许多细胞和组织因损伤而死亡，但由于自我诊断和自我修复不断进行，身体的完整功能不会受到损害。它将继续正常工作，因为身体的防御机制，包括许多免疫反应，将试图恢复其全部功能。因此，我们可以公正地问自己这个问题；从大自然中汲取灵感，以如此显著的效率来处理复杂性与不可靠性的问题，会不会更高效、成本更低？因此，我们提出的挑战是，在我们追求设计可靠的电子系统的过程中，适应在生物身上发现的生物过程，这些系统要求越来越复杂。虽然在这些领域已经取得了很大成就，其中大部分进展是由这一建议的两个合作者取得的，但仍有大量工作要做。本提案的目的是评估和应用新颖的、受生物学启发的过程和算法，用于在具有自我诊断和自我修复特性的硅上构建可靠的VLSI系统。受大自然的启发，我们的研究将适应生物系统的特性，如它们的多细胞组织和进化发展，以创造高效的电子系统。它还将应用生物过程和先天和获得性免疫系统的特性来帮助解决细胞、组织（子系统）和有机体（系统）水平的人工系统的可靠性和容错问题。我们的研究旨在为广泛应用的电子系统的生物学启发的独特设计方法铺平道路；从通信，通过计算和控制，到在敌对环境中操作的系统。

Powerful and sophisticated systems, from computers, through control systems, to 'conventional' household appliances have become a necessity in our modern way of life. In the modern world of digital electronics - virtually all of which is now built using VLSI technology - we are quite accustomed to the idea that hundreds of thousands, often millions, of individual components on a chip must work faultlessly over extended periods of time. Yet, it commonly requires only a single transistor to fail to have catastrophic consequences for the entire system. Imagine an automobile travelling at high speed in the fast line of a busy motorway. Suddenly, the electronic Engine Management Unit (EMU) develops a malfunction, the engine cuts out; soon after this the servo-assisted brakes and steering (that depend on the engine inlet manifold vacuum) both cease to function properly; a queue of stationary vehicles is fast approaching. The outcome of this scenario is left to the reader's imagination. This is a somewhat dramatic thought-experiment, but one that brings the safety-criticality and reliability aspects of some everyday digital electronic components in our lives into stark focus. The design of complex, but reliable, electronic systems and ensuring their long-term fault free operation is a major challenge we face today. This demand is even more pronounced in the case of electronic systems where their correct operation is imperative, e.g., anti-lock braking systems, fly-by-wire aircraft, space exploration, industrial control and shutdown systems; they should be able to operate correctly in the presence of faults and be fault tolerant. How can we design such reliable systems? Nature offers some remarkable examples dealing with complexity and unreliability. Living organisms, and in particular the human body, is one of the most complex systems ever known. Yet they possess an extremely high degree of reliability. Although local failures, due to harmful pathogens and environmental conditions, are common, the overall function of the organism is highly reliable. Many of the cells and tissues die as a result of damage, but because self-diagnostic and self-healing continues incessantly, full functional integrity of the body is not compromised. It will carry on working properly because the body's defence mechanism, comprising numerous immune responses, will try to restore its full functionality. We could therefore justly ask ourselves the question; would it be more efficient and less costly to draw inspiration from nature in how it deals with the complexity vs. unreliability issue with such a remarkable degree of efficiency? The challenge we propose to take on, therefore, is to adapt biological processes found in living beings in our pursuit of designing reliable electronic systems that demand an ever increasing level of complexity. Although a great deal has already been achieved in these areas, much of this progress having been made by the two collaborators in this proposal, there remains still a vast amount to be done. The objective of this proposal is to evaluate and apply novel, biologically inspired, processes and algorithms for building reliable VLSI systems on silicon that possess self-diagnostic and self-healing properties. Inspired by nature, our research will adapt properties of biological systems, such as their multi-cellular organisation and evolutionary development, to create efficient electronic systems. It will also apply biological processes and the characteristics of both the innate and the acquired immune system to help solve the reliability and fault tolerant issues of artificial systems at cell, tissue (subsystem) and also at organism (system) levels. Our research will aim to pave the way for a biologically inspired unique design approach for electronics systems across a wide range of applications; from communication, through computing and control, to systems operating in hostile environments.