**2.3 Engineering design methods**

*New Innovations in Engineering Education and Naval Engineering*

mentioned earlier.

**2.2 Engineering design processes**

ing characteristics [20–26]:

Even when real systems like engines, motor vehicles, home use machines, etc. are available, they are rarely analysed as whole systems because universities tend to compartmentalise knowledge. For example, in the case of a car engine, the student would have to draw on learnings from 'experts' in Thermodynamics, Mechanics of Machines, Fluid Mechanics, Materials & Manufacturing Engineering, Environmental Science, Electrical/Electronics, etc. These 'experts' would have taught the respective 'knowledge compartments' most generally, often, not even mentioning the engine. For the average student, integration of these 'compartments' in MED can be a very difficult first step to make, up the symbolic mountain

The usage principles occasionally come superficially in some final year projects. Even then however, the current approach to MED fails to motivate creativity in part, because it deals with already existing systems, whether imaginary or not. We can accept that it can lead to innovation as when an existing system is modified substantially to perform the same function 'better' or to perform others it originally was not intended for. We still note however, that limitations can be imposed by an insufficient grasp of the usage principles. To summarise therefore: to the extent that current treatment of MED at universities is theoretical analysis—driven, relying on existing systems and with limited concern for usage, it stunts both innovation and creativity. The intent of this chapter is to advocate and demonstrate a reversal of that approach, and align it with the practice in industry so that on one hand, students appreciate MED better, and on the other, they can find it easier to settle in industrial practice

In industrial practice, design approaches have been formalised to ensure as much detail on user requirements and on limiting constraints are taken care of, to get as cost effective (or profitable) a safe and marketable product as can be achieved. **Figure 2** shows some of the recommended processes in the literature. They all have the follow-

after they leave campus. **Figure 1** shows the two approaches, side by side.

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**Figure 1.**

*(a) Current and (b) proposed teaching and learning MED approaches.*

Nigel Cross [21] classifies engineering design methods used in the processes of **Figure 2** into two major complementary groups: the creative, and the rational ones. The former are characterised by their ability to stimulate thought processes, removing mental blockages and widening areas of search for solutions to the design problem. The latter on the other hand, systematically examine different issues at each stage of the processes in Section 2.2, also eventually solving the same problem. It is reported that some creative people detest the latter approaches because of their apparent prescriptive nature. Many others however, find the rational approaches most helpful, even complementary to the creative ones. **Tables 1** and **2** summarise methods in these two groups of approaches.

**Figure 2.** *Four examples of formal MED processes in industry.*


#### **Table 1.**

*Summary of creative engineering design methods.*


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**Figure 3.**

*watch?v=79CKBxt\_h-I).*

*Mechanical Engineering Design: Going over the Analysis-Synthesis Mountain to Seed Creativity*

We will now illustrate two cases of using some of the above approaches in an academic—rather than—an industrial environment. The first case is by the author himself. It exemplifies the creative design approach, and addresses an issue in solar energy engineering, of maximising useful energy yields from a flat-surfaced solar energy harnessing device. The second case shows a rational design approach, as taught to students in attempt to change MED from an analysis driven course, to a synthesis driven one. It builds on student knowledge gained from designing and constructing a multispeed fluid mixing vessel. The student designs a system for

A new hydro-mechanism for interconverting linear and rotary motion was invented—and is described in a South African patent by the Cape Peninsula University of Technology (CPUT) [29]. The primary motive of the invention was to create a mechanism that would be deployed in a novel single axis sun tracking device that relied on mechanical energy to turn a domestic home solar energy collecting surface during the day, and return it to a morning position any time before daybreak. **Figure 3** shows the mechanism being used in conjunction with a

The approach used was a slight modification of the Remo Reuben open process in **Figure 2**. There was branching at the stage of evaluating alternative concepts, which led to other, very different products altogether—discussed in

*3.1.2 Identification of need and formulation of engineering problems*

inadequate technical skill base had been established in Ref. [32].

A need for a new single axis sun tracking device, suitable for sub-Saharan Africa conditions of bi-hemispherical location, low credit and disposable incomes, and an

*The hydro mechanism driving a sun tracking PV panel (watch online video at: https://www.youtube.com/*

*DOI: http://dx.doi.org/10.5772/intechopen.85174*

essential oils extraction from African herbs.

**3.1 Case 1: invention of a new hydro mechanism for sun tracking**

**3. Case studies**

photovoltaic panel.

*3.1.1 Design processes*

Refs. [30, 31].

#### **Table 2.**

*Summary of rational engineering design methods.*

*Mechanical Engineering Design: Going over the Analysis-Synthesis Mountain to Seed Creativity DOI: http://dx.doi.org/10.5772/intechopen.85174*
