Planning and communicating prototype tests for the Nano Membrane Toilet: A critical review and proposed strategy

Urban sanitation in growing cities of the Global South presents particular challenges. This led to the Bill & Melinda Gates Foundation’s Reinvent The Toilet Challenge, which sparked the development of various non-sewered sanitation technologies like the Nano Membrane Toilet. Complex disruptive technologies like this entail an extensive product development process, including various types of prototype tests. While there is an abundance of literature discussing how to build prototypes, and the optimal number of tests, there has been little focus on how to plan and conduct tests, especially in a development endeavour of this complexity. Four approaches to testing are reviewed, and their strengths and weaknesses compared. A visualised testing strategy is proposed that encompasses the entire product development process and can be used to plan and communicate prototype tests for the Nano Membrane Toilet to ultimately achieve compliance with international standards

Integrating virtual and physical testing to accelerate the engineering product development process

Testing is essential in developing a successful complex engineering product. System level integration and testing can use between 35% and 50% of development resources. External factors such as legislation and customer requirements drive essential testing whilst internal factors such company experience, affordability and organizational practice profoundly affect the overall testing plan. The main objective of this paper is to understand how testing is integrated into the product development process and how different types of testing are scheduled across the stages of product development. The paper reports a case study in a diesel engine company where the balance of virtual and physical testing is a key concern in reducing design time and cost. Integrating physical and virtual testing is more than process optimization of time and cost. It contributes to recasting the design process in response to changes in customer requirements as well as to design changes which arise during testing. The importance of dependencies across components, subsystems and tests is highlighted using a model using Design Structure Matrices and the advantages of iterating physical and virtual testing are analysed particularly in facilitating task overlap to reduce product development duration

Prototype testing in product development: the case of the Nano Membrane Toilet.

The provision of safely managed sanitation in densely populated urban settlements of cities in low- and middle-income countries poses complex challenges. To address these challenges, Cranfield University is developing the Nano Membrane Toilet, a novel standalone household-level sanitation technology that operates off the grid and safely treats human waste while having an aspirational design. Developing such a complex novel product requires testing a multitude of prototypes in numerous ways. Since designing, building and testing the prototypes is often done by separate teams of various disciplines, the entire testing process requires a considerable amount of planning and communication. This thesis not only reports on field trials and laboratory testing of two prototypes of the Nano Membrane Toilet, but also investigates the under-explored field of planning and communicating prototype tests for complex product development processes. In a first trial, a prototype mechanical toilet flush is assessed in user tests and lab tests. It is shown to be liked by users of Urine Diversion Dehydration Toilets, and it appears to perform best when lubricated and with a silicone rubber with oil-bleed-effect for its swipe. A second round of tests explores settling and displacement as means of solid-liquid separation in the Toilets collection tank. Toilet paper is shown to inhibit settling of faeces, while a conical tank geometry promotes it. From a literature review and subsequent interviews with experts in prototype testing, a visual tool for planning and communication prototype tests for the Nano Membrane Toilet is developed, validated and refined into a generally applicable, modular version. This modular tool can be used to produce customised visual testing strategies for a variety of product development processes, to facilitate planning and communicating testing activities across interdisciplinary teams.PhD in Water, including Desig

The Role of Testing in Engineering Product Development Processes

Testing components, prototypes and products comprise essential, but time consuming and costly activities throughout the product development process particularly for complex iteratively designed products. The planning of testing is a critical challenge for these complex products for which market pressures demand shorter development times. A literature review identified that testing in the design process is a relatively under researched area. An extended case study in a diesel engine company was therefore conducted to explore how testing is integrated into the product development process and how different types of testing are planned across the stages of product development. The first part of this research study reports the empirical study. A framework resulting from this work is proposed which identifies the entities that characterise how testing should be planned. Motivated by needs of companies and research gaps identified in the literature review, the second part of this study focuses on three key problems for planning of testing in product development process: prioritisation of testing activities, scheduling of testing activities and managing the overlapping of testing and design activities. A method of integrating Quality Function Development (QFD) and Failure Modes and Effect Analysis (FMEA) for prioritising testing activities has been proposed, which can improve the current test prioritisation process of the company. A Multiple Domain Matrix (MDM) is created consisting of the components and associated tests of a product arranged in a format that allows the dependency and interrelationships between key parts and tests to be identified. This form of representation together with the proposed prioritisation method will improve the process of organising and scheduling the testing activities. The final study shows how virtual testing can mediate information flows between overlapping physical tests and (re)design and mitigate the risk associated with overlapping process. The study proposes a significant modification to the existing product development process configuration for design and testing. This reconfiguration makes explicit use of virtual testing which is an extension to Computer Aided Engineering. Virtual testing mirrors the testing process through modelling and simulation, as a distinct and significant activity. Virtual testing is used to (a) enhance and (b) replace some physical tests. Finally, this study assesses the costs and risks of overlaps and their amelioration through targeted virtual testing

Entwicklung einer Hochvolt-Traktionsbatterie als Produktgeneration 1 – Variationsinduzierte Validierungs- und Verifikationsplanung im Modell der PGE – Produktgenerationsentwicklung = Development of a high-voltage traction battery as a product generation 1 – Variation-induced validation and verification planning in the PGE model – Product Generation Engineering

Im Rahmen dieser Forschungsarbeit wird die Entwicklung von Hochvolt-Traktionsbatterien als Entwicklung einer Produktgeneration 1, kurz G1, im Modell der PGE – Produktgenerationsentwicklung untersucht. Bei einer G1-Entwicklung verfügt die entwickelnde Entität über keine direkte Vorgängergeneration als Referenz. Das Ziel ist, ein grundlegendes Verständnis zur Sonderform G1 sowie methodische Unterstützung hinsichtlich der Validierungs- und Verifikations-Aktivität in diesem Kontext zu entwickeln. Auf Basis teilnehmender Beobachtungen werden die beiden genannten Themen-schwerpunkte initial in der Forschungsumgebung analysiert. Der erste Teil der Arbeit betrachtet technische und prozessuale Herausforderungen bei der Entwicklung einer G1. In der kategorisierenden Auswertung von Experteninterviews kristallisieren sich elf Herausforderung heraus, die besonders in ihrer Häufung und Ausprägung als G1-typisch aufgefasst werden. Davon ausgehend wird eine Systematik zur prospektiven Einordnung von Produktentwicklungen hinsichtlich ihres G1-Charakters entwickelt. Die daraus resultierende Tendenzaussage, die anhand von sieben Kriterien hergeleitet wird, ermöglicht die Ableitung spezifischer Maßnahmen für die Produktentwicklung. Motiviert durch die Erkenntnis, dass in einer G1-Entwicklung mit einer erhöhten Anzahl an Variationen zu späten Entwicklungszeitpunkten gerechnet werden kann, wird im zweiten Teil eine Methodik für die variationsinduzierte Bestimmung des Testumfangs zur erfolgsorientierten Validierung und Verifikation entwickelt. Die Methodik basiert auf vier Schritten. Der Abgleich von erwartetem Entwicklungsrisiko im Zuge der Variationsimplementierung und Variationsursache stellt im ersten Schritt die Notwendigkeit der eingehenden Variation sicher. Basierend auf vorhandenen Werkzeugen, wie beispielsweise der Produkt-FMEA, wird im zweiten Schritt der Zusammenhang zwischen der eingehenden Variation und möglichen Tests abgebil-det. Darauf aufbauend werden in Schritt drei sowohl inhärent durch die spezifische Testauswahl als auch durch Variierung einzelner Parameter Validierungs- und Verifikations-Alternativen generiert. Die dadurch gewonnenen Alternativen werden im Anschluss in Schritt vier anhand der drei Dimensionen Zeit, Kosten, Qualität bewertet. Der wechselseitige Austausch mit dem Referenzsystem ermöglicht den Wissensaufbau und die Wiederverwendung der Informationen in jedem einzelnen Schritt. Die Anwendbarkeit sowohl der Einordnungssystematik als auch der Methodik zur variationsinduzierten Validierungs- und Verifikations-Planung wird an Beispielen im Rahmen der Entwicklung einer Hochvolt-Traktionsbatterie in der Forschungsumge-bung aufgezeigt. Die Methodik wird zudem mittels eines Fragebogens positiv evaluiert. Die abschließende Diskussion weist auf Limitationen und den kritischen Umgang bei Übertragung der Forschungsergebnisse in andere Umgebungen hin, deren Potenzial zur Weiterentwicklung im Ausblick aufgezeigt wird