Design Thinking

by Nigel Cross

  March argued that the two conventionally understood forms of reasoning – deductive and inductive – only apply logically to analytical and evaluative types of activity. But the type of activity that is most particularly associated with design is that of synthesis, for which there is no commonly acknowledged form of reasoning. March drew on the work of the philosopher C. S. Peirce to identify this missing concept of ‘abductive’ reasoning. According to Peirce, ‘Deduction proves that something must be; induction shows that something actually is operative; abduction suggests that something may be.’ It is this hypothesising of what may be, the act of producing proposals or conjectures, that is central to designing.

  Deductive reasoning is the reasoning of formal logic: if a is the same as b, and b is the same as c, then a is the same as c. Inductive reasoning is the logic of science: you observe all the swans in a given region; you note that each and every swan is white; you form the rule that ‘all swans are white’ (which you may find is false when you move to another region and discover some black swans). Abduction is the logic of design: you are asked to design a telephone for mature people; you know that mature people like clarity and elegant forms and colours; you propose a design with a smoothly contoured, soft-white case and clear, black buttons (one of many possible proposals for achieving clarity and elegance).

  Instead of ‘abductive’ reasoning, Lionel March preferred to call designing ‘productive reasoning’ because the designer has to produce a composition, or product. ‘Appositional reasoning’ also seems to be a suitable term to use, because the designer makes a proposal for a solution that, when juxtaposed to the problem, seems to be an apposite response. Unlike conventional logic, a design solution cannot be derived directly from the problem, but can only be matched to it. Unlike the scientist, who searches for many cases to substantiate a rule, and then one case to falsify it, the designer can be gratified in being able to produce just one satisfactory case that gives an appropriate result.

  A comprehensive analysis of why the classic methods of reasoning in problem solving are inappropriate in design has been provided by Henrik Gedenryd. Working from a cognitive science perspective, and applying it especially in the context of interaction design, Gedenryd argued against the view of cognition as a purely rational, ‘intra-mental’ (i.e. solely within the mind) activity, and in favour of recognising it as a practical, interactive activity. He concluded that ‘the mind working on its own is only a circumscribed portion of the full cognitive system’; the full system comprises mind, action and world, or a combination of thinking and acting within a physical environment. The designer’s natural way of working encompasses that larger system through interacting with temporary models of the situation being designed for. The range of design techniques such as sketching, prototyping, mockups, scenarios, etc., enable the designer to make ‘an inquiry into the future situation of use’. These techniques ‘make the world a part of cognition’, and provide the designer with a set of ‘situating strategies’. Hence, Gedenryd provided a theoretical understanding for the important role of these techniques and strategies in design. He showed that abstract thought alone cannot satisfactorily perform the complex task of designing.

  The Natural Intelligence of Design

  The most significant outcome from the varied studies and research into design practice has been the growth of respect for the inherent, natural intelligence that is manifested in design ability. Early attempts to reshape the process of design into something more rational and systematic were founded perhaps on a disrespect for this natural design ability, and a strong desire to impose order onto design thinking. There was a desire to recast design almost as a form of science, and to replace conventional design activities with completely new ones, based on technical rationality.

  These original aims may well have been an understandable reaction to a previous view of design ability as an ineffable, mysterious art. There are still those who regard design thinking as ineffable, and there are still those whose lack of understanding of design ability still leads them into attempts to reformulate design activities in inappropriate ways. However, at the core of the discipline of design there is now a more mature, informed and enlightened view of design ability. This mature view has grown from a better, research-based understanding of the nature of design ability, from analysis of its strengths and weaknesses, and from a desire to defend and nurture that ability.

  As we have seen, one way of studying design thinking that has helped particularly to develop that better understanding has been through case studies of designers at work. The next part of this book begins a series of case studies of designers and design activity that will occur throughout the book. The case studies are intended to provide resources for the study of high-quality design thinking, with information and data drawn from both interviews and experimental investigations. In the next two chapters we will study two outstanding designers, with the chapters based on my own interviews and conversations with the designers.

  Sources

  Full references are included in the Bibliography.

  Larry Bucciarelli: Designing Engineers.

  Jane Darke: The primary generator and the design process, Design Studies.

  Robert Davies: A Psychological Enquiry into the Origination and Implementation of Ideas.

  Robert Davies and Reg Talbot: Experiencing ideas, Design Studies.

  Henrik Gedenryd: How Designers Work.

  Bryan Lawson: Design In Mind.

  Peter Levin: Decision Making in Urban Design.

  Peter Lloyd and Dirk Snelders: What was Philippe Starck thinking of? Design Studies.

  Lionel March: The Logic of Design, in The Architecture of Form.

  Dianne Murray: An Ethnographic Study of Graphic Designers, in European Conference on Computer Supported Cooperative Work.

  Peter Rowe: Design Thinking.

  Donald Schön: The Reflective Practitioner.

  2

  Designing to Win

  Our first case study is of an outstanding designer who has had a long and distinguished record as a highly successful and highly innovative designer in a highly competitive environment, that of Formula One racing car design. As a young graduate engineer, Gordon Murray moved to Britain from his home in South Africa where he had built and raced his own car in club events. He joined the Brabham Formula One racing car team as a designer-draughtsman, and quite soon was appointed chief designer. For twelve years, he carried the major responsibility for the design of a series of innovative and frequently successful racing cars. Brabham cars designed by him were driven by Nelson Piquet to win the World Championship in 1981 and 1983. In 1987, Gordon Murray moved to the McLaren Formula One team as technical director. Through all four race seasons from 1988 to 1991, McLaren cars designed by Murray and his team, driven by Alain Prost and Ayrton Senna, won both the Drivers’ Championship and the Constructors’ Championship. In all, Gordon Murray’s cars won 51 Grand Prix races.

  Gordon Murray then became technical director of McLaren Cars Limited, an offshoot of the Formula One team, and became responsible for the design and development of a completely new, road-going ‘super car’ – the McLaren F1 (Figure 2.1), which attracted immense attention as the ‘ultimate’ sports car. As well as many technical innovations, the F1 featured a novel seating arrangement, with the driver positioned centrally and two passenger seats beside but slightly behind the driver, in an ‘arrowhead’ configuration (Figure 2.2).

  2.1 The McLaren F1.

  2.2 (a) Gordon Murray’s sketch for the McLaren F1, showing the three-person seating arrangement with passengers slightly behind the central driver; (b) overhead view of the McLaren F1; (c) detail drawing side/cutaway-view of the McLaren F1.

  The F1 was designed on the same rigorous principles as a Formula One car. These principles were proved when GTR versions of the F1 were produced for competition in sports car races; at their first outing, the 1995 Le Mans 24-hours race, McLaren F1s came first, third, fourth and fifth. Gordon M
urray went on to design another super car, the Mercedes McLaren SLR, and then took a radical change of direction into the design of a small, cheap city-car, the T.25, first announced in 2008, and then as the T.27 electric-powered version in 2009.

  Formula One Designing

  Formula One racing car design is, of course, significantly different from almost every other kind of design domain. Gordon Murray likens it to war. Although he has never been in a war, engineering and technological development in wartime is the closest analogy to Formula One he can think of, with resources – human, financial and technical – being poured into the design and construction of machines that must have, and maintain, a vital performance edge over those of the ‘enemy’. Throughout the nine-month Formula One season there is a battle to be fought on a different field every two weeks, with a new campaign starting again every year.

  This constant war-like atmosphere creates tremendous pressure, particularly on someone in the position Gordon Murray was in for many years with Brabham of being totally in control of, and responsible for, the complete technical operation: designing, constructing, testing, racing and organising, throughout the year, and from one year to the next. With the calendar of Grand Prix races fixed in advance, there is also constant time pressure, with no possibility allowed of missing a single race or practice session.

  There are also, of course, the ‘rules of engagement’ for this perpetual ‘war’: the Formula One technical and sporting regulations, which minutely and precisely specify the physical and operational limits within which the teams must compete. Gordon Murray regards the regulations (the constraints, or design specification) of racing car design, along with its intense pressure and competition, as fundamental to the necessity to innovate. With every team working within the same constraints, only innovation, coupled with constant refinement and improvement, can provide the competitive edge. In other design fields, as he has discovered, the lack of regulations can be slightly bewildering, allowing the designer to wander at whim in a very loosely bounded solution space. Although he has tried working in other design fields, Gordon Murray seems to find them uncomfortable. Outside of racing car design he thinks that there just is not enough pressure on the designer, nor tight enough regulations, nor strong enough competition, for radical, innovative design thinking.

  Many other designers might suggest that the one significant constraint they have to design within, which Formula One designers do not have, is that of money – the financial limit on what their product can cost. But Gordon Murray does not entirely agree. He claims that at Brabham the budgets were relatively small for Formula One, perhaps only one-third of the budgets of bigger teams, but that did not limit their innovation potential. A relative shortage of money meant the Brabham team might do less testing, or carry fewer spares, but that did not stop innovation which, he claims, comes down to people and their environment. ‘It comes from the environment and the situation you’re in; you’re governed by these regulations; you’re in this sort of a war situation, you’ve got a battle every two weeks; and you’re desperate to try and think of things all the time – alongside all the normal design [improvement] processes which are more laborious … I can’t tell you how hyper it is, relative to architecture, bridge design, furniture design …’ And as we will see later, in his city-car design he applied his same principles of design thinking within a context of saving every penny of cost.

  Radical Innovations

  Throughout a racing season there is constant work to make continuous improvements and adjustments to the current car design. These may be responses to obvious shortcomings such as component failures, or to the drivers’ comments about the car’s performance and handling, either in general or in relation to certain corners or features of certain race circuits. The performance improvements aimed for may seem incredibly tiny by other standards – perhaps one-tenth of a second on a lap – but they can make the difference between being first or second in the race. And at the same time, every other team is also making constant improvements, so the situation is never static.

  This creates constant, relentless pressure on the designer to keep making design improvements. But there is a limit to what can be achieved with any car design, before a jump has to be made to basically a new design, an innovation. As Gordon says, ‘Given the situation and the pressure at any one time, you do get to the brick wall. I mean, you’re doing all these normal modifications, you know you can’t go any quicker, you need to make the step forward.’ Typically, such a step forward happens during the short close-season, when every team seeks to start the coming new season with an advantage over its rivals.

  The constant pressure during the racing season breeds a fervour to succeed that never stops, Gordon says: ‘You gotta go quicker, gotta go quicker.’ The pressure then to come up with something new becomes intense, and the responsibility is all yours, ‘and you get more and more sort of – panicky, almost’.

  The situation can only be resolved by a new car design. In many instances, and for most teams, this will be a new version of the previous season’s car; perhaps a new chassis, new suspension, or new engine to be accommodated; perhaps a change in regulations to be met. For Gordon Murray it would often mean trying a ‘step forward’, a radical new concept. In the midst of the pressure, the fervour, the panic, he ‘used to get breakthroughs, I mean I used to get like suddenly a mental block’s lifted’. These breakthroughs would come as a sudden illumination: ‘I know it’s a cliché, but I did have a lot of good ideas in the bath, I really did.’ The illuminations came, again in classical form, after long periods of preoccupation with the problem, and after what Gordon Murray emphasises as the most important factor in innovative design, of reconsidering the problem situation from first principles; he stresses the need to ‘keep looking back at fundamental physical principles’.

  Another crucial factor is the motivation to carry the bright idea through into detailed implementation. Again, intense pressure, even in the brief close-season, ensures that ideas that look certain to be winners will be pushed through to detailed implementation with the same fervour as in the racing season. Other possibly good ideas are discarded on a rapid evaluation of their implications for a car’s weight, performance or handling. In racing car design, it is not just a matter of having ideas, but of really implementing ideas that are going to improve performance, of having to ‘do it’, as Gordon says; ‘You have the idea, but you have to do it, and that’s what cuts the bullshit out.’

  Hydro-pneumatic Suspension

  As one example of radical innovation, Gordon Murray refers to the development at Brabham of a hydro-pneumatic suspension system. In the early 1980s, the Formula One governing body, FISA, became concerned to reduce the ‘ground effect’ on racing cars. This effect had been pioneered on the Lotus team’s cars; smooth underbodies lying very close to the ground, side skirts and careful aerodynamic design provided a ground-effect downforce which increased the car’s grip on the track surface. This meant much higher cornering speeds were possible, until some people were worried about the heavy g-force effects that were being imposed on the drivers that might cause them to lose consciousness. FISA decided to ban ‘sliding’ skirts, but allowed fixed skirts and set a minimum underbody ground clearance of 6 cm. For Gordon Murray this sudden change in regulations was a stimulus to innovation.

  What turned out to be his first World Championship-winning car ‘came absolutely from the regulation change. You sit there and you read the regulations and think, how we are going to do it? How the hell can we get ground effect back? What [the regulations] said was “At all times the car will have a 6cm gap between the bodywork and the ground … and there can be no driver-operated device to change that gap.” And everybody looked at it, and built cars with 6cm gaps … and I looked at it and I thought, if that 6cm gap could be a 1cm gap I could double the downforce on the car; and it’s going to go down to a 1cm gap at some point, like [under braking] at the end of the straight. So if I can make a physical thi
ng … that drives the car down on its own, and holds the car down on its own without any mechanical aid or button or electrics or anything, it’s legal. So in three months we developed a hydro-pneumatic suspension.’

  Gordon Murray’s thinking on this, and he says it came as a sudden illumination, was that the authorities had to accept that at some points during a race, any car’s ground clearance is going to be less than the 6cm minimum simply because of the effects of braking, or roll on corners, etc. Knowing that any driver-operated, mechanical device to alter the ground clearance was illegal, he focused on the physical forces, the basic physics, the ‘bits of nature’, that act on a car in motion. The braking and cornering forces he felt unable to work with because of their asymmetrical effects on the car, but the downforce from air pressure on a moving car could, if the car was correctly designed aerodynamically, push the car down equally over its whole length and width. The design challenge, therefore, was to let the natural downforce push the car down at speed, and then somehow to keep it down when it slowed for corners, and then allow the car to return to 6cm clearance at standstill.

  The ingenious solution that Gordon Murray developed incorporated hydro-pneumatic suspension struts at each wheel, connected to hydraulic fluid reservoirs. As the car went faster, the natural downforce of airflow pushed the body lower on its suspension and the hydraulic fluid in each suspension strut was pushed out into the reservoirs. The trick then was to find a way of letting the fluid return to the suspension struts only very slowly when the car slowed down. At corners, the suspension would stay low, but on slowing down and stopping at the end of the race, the fluid would return from the reservoirs to the suspension struts, giving 6cm ground clearance.