M.C. van der Voort

Robotic control of a traditional flexible endoscope for therapy

In therapeutic flexible endoscopy a team of physician and assistant(s) is required to control all independent translations and rotations of the flexible endoscope and its instruments. As a consequence the physician lacks valuable force feedback information on tissue interaction, communication errors easily occur, and procedures are not cost-effective. Current tools are not suitable for performing therapeutic procedures in an intuitive and user-friendly way by one person. A shift from more invasive surgical procedures that require external incisions to endoluminal procedures that use the natural body openings could be expected if enabling techniques were available. This paper describes the design and evaluation of a robotic system which interacts with traditional flexible endoscopes to perform therapeutic procedures that require advanced maneuverability. The physician uses one multi-degree-of-freedom input device to control camera steering as well as shaft manipulation of the motorized flexible endoscope, while the other hand is able to manipulate instruments. We identified critical use aspects that need to be addressed in the robotic setup. A proof-of-principle setup was built and evaluated to judge the usability of our system. Results show that robotic endoscope control increases efficiency and satisfaction. Participants valued its intuitiveness, its accuracy, the feeling of being in control, and its single-person setup. Future work will concentrate on the design of a system that is fully functional and takes safety, cleanability, and easy positioning close to the patient into account.

Synergy of Technical Specifications, Functional Specifications and Scenarios in Requirements Specifications

In the (mechanical) design process, the requirements specification is a formal registration of the conditions that are imposed on a new or altered product design, both preceding as well as during the corresponding product development cycle. For a long time, the use of technical specifications has prevailed in the establishment of such requirements specifications. However, gradually, there is an appreciation for the fact that sheer technical specifications may inadvertently fix constraints and possibilities too early in the process. Moreover, it is recognized that technical specifications are unsuitable to adequately address the role of unquantifiable aspects that play important roles in the development cycle. Using functional specifications and scenarios respectively may aid in addressing these problems. Considering the importance of having an effective requirements specification, the coherence, synergy and specifics of technical specifications, functional specifications and scenarios as part of the requirements specification are addressed. This publication focuses on the different roles, limitations and added values of the constituents of the requirements specification.

Haptic virtual prototyping for design and assessment of gear-shifts

Traditionally, a designer forms the link between the customer and the final product by interpreting customer demands and desires and translating them into geometry. By combining 3D CAD systems and software tools for analysis, a designer is able to examine whether the created geometry complies with these customer demands and desires. However, in the process of translation and examination, a measure of subjectivity is added to the design. A virtual prototyping environment (VPE) can be created by utilizing Virtual Reality technology, in which the customer is able to specify the Product’s behavior in a direct way, i.e. without designer interference. In this way, not only is the design process is made more objective, but also significant amounts of time and money are saved since less physical prototypes are required. This paper describes the design and evaluation of a VPE for manually operated gearboxes in passenger cars. Based on measurements taken of the gearlever on a test vehicle, an application is designed that simulates its gearshift feel. This application incorporates a commercially available haptic device. In order to determine whether the virtual gearshift feel conforms with the real gearshift feel, a usability test is performed. The test group considered the feel of the simulated “virtual” gearshift to be quite similar to the “real” gearshift feel of a test vehicle. By further developing this VPE, it should become possible to define gearshift feel by customer assessment through haptic simulation, after which the physical gearbox is designed in such a way that it matches the preferred shifting behavior.

User centred methods for gathering VR design tool requirements

This paper addresses the use of VR to facilitate design tasks in the early stages of a product design process. A preliminary exploratory study, involving over thirty interviews amongst four industrial partners, revealed only few occurrences of VR being used in the early stages of design. While the potential benefits of the applications are generally acknowledged, product designers lack the appropriate design tools that allow them to quickly and easily create the application. The research presented in this paper applies user-centred design principles to identify requirements for useful, usable and accessible VR design tools. The primary challenge in gathering such requirements is the lack of experience product designers generally have with VR technologies; product designers can not provide reliable requirements for tools they have never seen or used. We present a sequence of three concrete steps that provide product designers with sufficient information to express tool requirements, without developing extensive prototypes. The three methods have been developed and applied in an industrial case study, as part of a larger research project. The paper outlines this research context, the three methods and the lessons learned from the case study.

Understanding actor perspectives regarding challenges for integrated river basin management

ABSTRACT Integrated river basin management increases technical as well as management and governance complexity. In this multidisciplinary setting, actors, from their different backgrounds, frame both issues and solutions differently. To resolve conflicts, it is important to recognize – and to not ignore – the existence of contending social framings. A better understanding is needed of how actors frame issues and solutions in integrated river basin management. To gain this better understanding, semi-structured interviews were conducted with Dutch river basin management actors following Sense-making methodology. Three challenges were identified where respondents framed both the issue and solution differently: (1) creating flexibility in a controlled river system; (2) sustaining the integrated approach in the maintenance of floodplains; and (3) formulating future river basin management policies to adapt to climate change. Cultural Theory was subsequently used to analyse how respondents construct perspectives towards these challenges. The analysis showed how actors use different rationalities in constructing these perspectives. As an implication, it is important for actors to recognize and acknowledge these perspectives in integrated river basin management decision-making. New tools, embedded in learning environments, are needed to facilitate exchanging and understanding actors’ perspectives.

Creating useful, usable and accessible VR design tools: an EUD-based approach

Virtual Reality (VR) tools create an alternative reality in which worlds, objects and characters can be experienced that may not yet be experienced in reality. As such, VR can help product designers in the early stages of the product development process with evaluating virtual product concepts. The current set of VR tools and VR development toolkits however targets programmers and computer experts rather than product designers, thus limiting the adoption of this technology in the field of product design. The research presented in this paper applies End-User Development (EUD) principles to let designers describe, create and evaluate VR design tools that are useful, usable and accessible.

A new user centered approach to the design of driver support systems

This paper presents a new product design method that gives users a proactive role in the design process. Within a dedicated design environment, users are allowed to create their own designs and immediately test these in a wide variety of scenarios. By letting users realistically interact with their personal creations, designers can quickly and reliably pinpoint their needs and preferences. At the same time, good designs are generated. To evaluate the new method, it was applied to a design case: the design of a lane change support system. It was found that the new method offers added value for the design of driver support systems.