Tips on making tools for space

For many of us, the headline-grabbing results returned from modern astronomy and space science missions make impressive reading in the morning papers. However, behind these front-page pictures there is an exciting interdisciplinary field devoted to the design, fabrication, testing and operation of space instrumentation. In this book, four authors with extensive experience of space instrumentation provide an overview of the field and practical advice on how to build space instruments.

First, the incredibly hostile environment in which space instruments must operate is explored and the implications for design considered. From this sobering starting point, we are taken through mechanical and thermal design. The fundamentals of each topic are briefly covered so that extensive prior knowledge is not necessarily required. A number of useful tutorial calculations are provided which help to fix ideas. These calculations are usually of the kind experienced in practice, for example determining payload attachment loads experienced by restraining bolts or determining the required properties of thermal insulating blankets.

Following on from these general aspects of space engineering, the more detailed design of space instrument electronics is covered. This chapter again provides practical advice on circuit design and also telemetry coding. A section on attitude determination is included, which is certainly of interest to space instrument designers. However, there is also a short section on attitude control. While instrument designers will certainly be interested in this topic, attitude determination and control are usually the responsibility of those designing and fabricating the main spacecraft bus.

The penultimate chapter in the book investigates the management of large space instrument projects and the control of the project schedule. Again, the experience of the authors shines through here. While many books on general spacecraft engineering contain woolly information on GANT and PERT charts, it takes experience to note gems of wisdom such as that "few instrument-size or small satellite projects really need PERT planning techniques, impressive though they may seem to the outsider". Lastly, there is a brief discussion of small satellites. Although still open to debate, it is generally agreed that small satellites offer significant advantages for at least some missions. Here the authors provide their own views and note that due to their low cost, small satellites only justify the use of fairly basic quality assurance procedures, particularly since the success rate of launch vehicles is still quite awful.

The level of practical advice is one of the most attractive and useful aspects of this book. While we are given an overview of, for example, designing a regulated power supply or a low-noise amplifier, we are also warned of potential failures and pitfalls, how to screen batches of components before fabrication and even advice on appropriate fusing. This is a level of practical detail not often seen in books on spacecraft engineering and is most welcome.

While the book provides excellent coverage of the engineering of space instrument systems, it would have been useful to have some information on how particular instruments are designed. Certainly, there is a chapter on space optics, but other instruments are missing. How are field and particle instruments designed, or indeed more complex devices such as X-ray telescopes? Perhaps I am expecting too much breadth from a single book.

The book is likely to appeal to university researchers with an interest in building their own instruments for future missions, or indeed engineers in the space industry tasked with an instrument design or fabrication contract. In addition, many amateur astronomers will no doubt be fascinated by the details of space instrument design. In summary, this is an excellent book covering the field in depth and includes extensive practical advice which can only come from those with many years of hands-on experience.

Colin R. McInnes is reader in space systems engineering, University of Glasgow.