Intuitive Design Method Research Articles

A human-machine collaboration frame in daylighting optimization of semi-outdoor space design by using phased synergistic method: A case study

The semi-outdoor space (SOS) of a building is a valuable activity space and a microclimate transition zone for occupants. Current parametric and optimization methods for SOS design limit the flexibility and complexity of the design process and lack human-machine interaction, which can lead to design results that do not meet specific requirements and diverge significantly from designer expectations. Therefore, this paper proposes a new dynamic and in-depth human-machine collaborative design method to solve multi-level, complex semi-outdoor space design problems and provide preferable daylighting performance. A phased synergistic method (PSM) is proposed based on hierarchical iterations of design variables. The new method allows for integrating existing design tools and expands their optimization scope to accommodate early design stages with ambiguous requirements. A case study building in Guangzhou, China, is used to showcase the design process and daylighting performance evaluation results. The case study uses the intuitive design method (IDM) and the non-phased method (NPM) results for performance and usability comparison. The study shows that the new method can find spatial combinations with better daylighting performance. It also illustrates the positive effect of adequate human-machine interaction in enhancing building performance and form optimization.

Performance-based Generative Shape Grammar Method: Energy Efficient Facade Design for Fully Glazed Multi-Storied Office Building - Hot and Humid Climate, Chennai, India

The traditional building form design or form-making is an intuitive design method that is neither efficient nor competent for energy-efficient façade design. The form-making design approach threatens sustainable development in India. This paper discusses the new tread of form-finding, a process in which the framework is set for parameters to interact. It suggests a performance-based shape grammar (PBSG) generative design method for façade finding and evaluates it as an energy-efficient facade design method for FGM office buildings for India's hot and humid climate.A research method to develop PBSG rules for a given project framework was demonstrated by redesigning a case sample site and evaluating the existing FGM office building in the sample site. The PBSG methods in two stages apply multiple rules, first for form-finding and later for façade plane-finding for energy efficiency.It was observed that the SG resultant generated form was 42% more energy-efficient than the existing design using the same envelope materials, HVAC equipment, development regulations, and context.The outcome of this study provides a framework for a generative design process using PBSG in the early design stages and proves to be an energy-efficient design method for India's hot and humid climate.

Quasi-Developable B-Spline Surface Design with Control Rulings

An intuitive design method is proposed for generating developable ruled B-spline surfaces from a sequence of straight line segments indicating the surface shape. The first and last line segments are enforced to be the head and tail ruling lines of the resulting surface while the interior lines are required to approximate rulings on the resulting surface as much as possible. This manner of developable surface design is conceptually similar to the popular way of the freeform curve and surface design in the CAD community, observing that a developable ruled surface is a single parameter family of straight lines. This new design mode of the developable surface also provides more flexibility than the widely employed way of developable surface design from two boundary curves of the surface. The problem is treated by numerical optimization methods with which a particular level of distance error is allowed. We thus provide an effective tool for creating surfaces with a high degree of developability when the input control rulings do not lie in exact developable surfaces. We consider this ability as the superiority over analytical methods in that it can deal with arbitrary design inputs and find practically useful results.

Bending-active kirigami

Kirigami techniques use prescribed arrangements of cuts and fold lines to transform 2D sheet materials into complex 3D forms. These sheet transformations occur via elastic deformations, rigid folding motions, and/or pop-up mechanisms; design techniques for kirigami patterns are correspondingly based on mechanics, kinematics, and physical prototyping. This paper proposes a new family of pop-up kirigami patterns termed ‘bending-active kirigami’, which transform flat sheets into approximated double-curved surfaces using a simple 1-DOF actuation mechanism. A pattern design technique is first developed from a combination of the well-known ‘elastica’ solution for the large elastic deformation of slender rods, with the kinematic constraints imposed by a kirigami pop-up mechanism. This combination creates a rapid and intuitive design method for specification of a formed surface and its constituent kirigami pattern. An extended family of patterns are then developed based on other elastica solutions and pop-up mechanism types. Finally, a bending-active kirigami pattern is applied to the design of a deployable structure, with measurements of a physical prototype used to verify the developed design method.

Analysis of the inherent adaptability of basic truss and frame modules by means of an extended method of influence matrices

New approaches and technologies are needed to counter the effects of climate change and mitigate the depletion of material resources. A possible solution are adaptive load-bearing structures, i.e., structures that are equipped with sensors, actuators and control units, enabling the structure to optimise its current stress state. This requires new research regarding the overall structural design of material- and emission-efficient adaptive structures. Existing approaches employ sensitivity matrices or optimality criteria in optimization formulations to design adaptive load bearing structures and discuss the quality of the design based on the results. This paper presents the method of actuation influence matrices, which are a type of sensitivity matrix that can be used quantify the inherent adaptability of a structure. The aim is to develop an intuitive design method for adaptive structures. After a brief derivation of the influence matrices, the methodology is illustrated using three basic bracing systems – a truss, a frame and a diagonally braced frame – as example, demonstrating the relationship between structural topology and inherent adaptability. While the assessment of an adaptive structure’s quality depends on the specific use case and control objective, it is proposed that truss systems are good candidates for adaptive structures due to their inherent adaptability.

Topological design of lattice materials with application to underwater sound insulation

Lattice materials with low acoustic impedance can be treated as acoustic soft boundaries compared to water and have potential application to underwater sound insulation. However, limited by the intuitive design method, only a few simple topologies have been reported, leaving a huge design space and potential performance of lattice materials untapped. This paper shows that lattice materials with low acoustic impedance can be systematically designed using topology optimization combined with the homogenization method. Aside from the material occupation, the azimuth of lattice material as an additional design variable is added to the optimization formulation. By imposing different effective modulus constraints, the results show that two types of bi-mode lattice materials can achieve extremely low acoustic impedance alongside an optimal azimuth. The first type of bi-mode lattice material possesses strong anisotropy and a positive Poisson’s ratio, whereas the second has weak anisotropy and a negative Poisson’s ratio. The optimal azimuth for minimum acoustic impedance is dependent on the degree of anisotropy of bi-mode materials. The minimum value of acoustic impedance is associated not only with the degree of anisotropy but also with feature parameters related to easy-deformation mode. Based on the topology optimized lattice materials, various acoustic metascreens with deep sub-wavelength thickness are proposed to shield underwater sound in a low and broad frequency range. Finally, two samples among the designed acoustic metascreens are fabricated and tested in a water-filled tube. Despite that the thickness of both metascreens is only 17 mm, the experimental results show that the sound transmission is reduced averagely by over 17 dB from 500 Hz to 2000 Hz.

Design of laminated bamboo fishing boat with local cultural heritage using electric motor to support fishing tourism in Pasuruan, East Java

Fishing has been one of the main sources of livelihood in Indonesia, to the point that it gives birth to numerous fishing culture preserved by the locals in the country. However, the development of Indonesia’s fishing tourism is quite slow, despite its identity as an archipelagic state. In attempt to boost the fishing tourism sector, this study proposes a design of a fishing boat with a touch of Pasuruan cultural heritage, a region in East Java. The design is hoped to attract the tourists’ attention by presenting them a local heritage fishing experience. Laminated bamboo is utilised as the boat’s material so it can be recycled as furniture when no longer in use. The boat’s main dimensions are obtained by means of intuitive design method. Technical calculations including the boat’s resistance and propulsion, required power and stability are carried out subsequently. The main dimensions for this boat are: LoA = 8.2 m; B = 1.1 m; H = 0.6 m; and T = 0.42 m. The service speed is set to be 7.5 knots. While the required power to move this boat is around 7.481 kW to power an electrical motor with 25 HP.

A Holographic Antenna Approach for Surface Wave Control in Microstrip Antenna Applications

A holographic antenna inspired structure is used to control the surface wave (SW) excited by a microstrip patch antenna. The hologram is designed to support a periodic leaky-wave which radiates at broadside and enhances the radiation of the patch while suppressing the horizontal lobe. In this design, the holographic approach is adapted for patch antenna applications where the SW wavelengths are comparable to the freespace wavelength. This is achieved by introducing dual phase-shifting metallic dipoles with periodic spacings. This paper discusses a simple and intuitive design method for the holographic surface, as well as its integration with the microstrip patch. The initial design concept was developed by assuming small perturbation to the SW, which was subsequently verified through full-wave simulations and prototype measurements. The results verified the improvements in the broadside gain and SW efficiency of the microstrip patch at the cost of increased area.

Available rotation capacity of composite bridge plate girders under negative moment and shear

This paper presents a study of the behaviour of slender composite plate girders under negative bending moment and shear. It is known that at composite bridge intermediate supports, the slender composite beams have very limited ductility, which has led to the adoption of elastic methods for the design of these members. However, this elastic design is time-consuming and does not correspond with real beam behaviour. In order to propose a simpler and more intuitive design method which corresponds better with real beam behaviour, the support region limited ductility must be quantified. In this study, slender composite beam ductility under shear and negative bending is investigated, using a numerical model developed specifically for this purpose. On the basis of the parametric analysis results, a simple analytical model for quantifying the slender composite beam support region ductility is proposed and verified.

Methodology for bringing the intuitive design method's framework into design activities

Today, virtually all designers acknowledge that of the four fundamental activities which make up their daily tasks, the area that remains deficient is creativity, which they cannot systematize. Indeed, while the collection, construction and growth factors can be estimated and scheduled in terms of both deadlines and relevance, designers cannot guarantee the same objectives for creativity. The present investigations into the relevance of the assistance that a method can offer designers have led to the conclusion that TRIZ can provide a definite contribution, since it increases the relevance of the creative phase in design through systematization. This article describes how this methodological system, stemming from TRIZ, was introduced into the design process in the company.

DATA-DRIVEN DESIGN OF HMM TOPOLOGY FOR ONLINE HANDWRITING RECOGNITION

Although HMM is widely used for online handwriting recognition, there is no simple and well-established method of designing the HMM topology. We propose a data-driven systematic method to design HMM topology. Data samples in a single pattern class are structurally simplified into a sequence of straight-line segments, and then these simplified representations of the samples are clustered. An HMM is constructed for each of these clusters, by assigning a state to each straight-line segments. Then the resulting multiple models of the class are combined to form an architecture of a multiple parallel-path HMM, which behaves as a single HMM. To avoid excessive growing of the number of the states, parameter tying is applied such that structural similarity among patterns is reflected. Experiments on online Hangul recognition showed about 19% of error reductions, compared to the intuitive design method.

Design method evaluation—an experiment with corridor selection

The improvement of the process of design requires the evaluation of alternative design methods. A framework for evaluating graphically based, intuitive design methods is (1) solve a set of problems with a proven algorithm, (2) have a sample of designers solve the same set of problems, and (3) compare the results to identify the success of each designer or design method. A proto-typical experiment using the problem of corridor selection is used to illustrate the approach, with solutions obtained by twelve students being compared to solutions obtained by discrete dynamic programming for a set of three problems. An important distinction is drawn between measuring the success of the solution vs the success of the problem solving procedure. An extension to evaluate the handling of separately defined objectives is suggested, and questions concerning the stability of a solution with respect to minor changes in the algorithms identified.