scholarly journals Research and development of decision-making methods for creating 3d objects in mechanical engineering

2018 ◽  
Vol 224 ◽  
pp. 02002
Author(s):  
Alan Kumaritov ◽  
Ekaterina Sokolova

The analysis of the criterion of integral proximity of a clear / fuzzy truth value to the value of absolute truth is carried out in this work. Confirmation of the possibility of using algorithms to create three-dimensional objects in engineering.

2017 ◽  
Vol 906 ◽  
pp. 121-130 ◽  
Author(s):  
V. Korzhyk ◽  
V. Khaskin ◽  
O. Voitenko ◽  
Volodymyr Sydorets ◽  
O. Dolianovskaia

Using of welding technologies to produce metal volume objects allows considerable lowering of their manufacturing cost at simultaneous increase in productivity, compared to SLS-and SLM-processes. The most perspective welding technology of additive manufacturing of three-dimensional objects is plasma-arc technology with application of wires or powders. It allows creating at comparatively low heat input quality volumetric products with wall thickness from 3 to 50 mm from alloys based on Fe, Ni, Co, Cu, Ti, Al, as well as composite materials, containing refractory components.


2018 ◽  
Author(s):  
Lina K. Klein ◽  
Guido Maiello ◽  
Vivian C. Paulun ◽  
Roland W. Fleming

AbstractWe rarely experience difficulty picking up objects, yet of all potential contact points on the surface, only a small proportion yield effective grasps. Here, we present extensive behavioral data alongside a normative model that correctly predicts human precision grasping of unfamiliar 3D objects. We tracked participants’ forefinger and thumb as they picked up objects of 10 wood and brass cubes configured to tease apart effects of shape, weight, orientation, and mass distribution. Grasps were highly systematic and consistent across repetitions and participants. We employed these data to construct a model which combines five cost functions related to force closure, torque, natural grasp axis, grasp aperture, and visibility. Even without free parameters, the model predicts individual grasps almost as well as different individuals predict one another’s, but fitting weights reveals the relative importance of the different constraints. The model also accurately predicts human grasps on novel 3D-printed objects with more naturalistic geometries and is robust to perturbations in its key parameters. Together, the findings provide a unified account of how we successfully grasp objects of different 3D shape, orientation, mass, and mass distribution.Author SummaryA model based on extensive behavioral data unifies the varied and fragmented literature on human grasp selection by correctly predicting human grasps across a wide variety of conditions.


2020 ◽  
Author(s):  
M.A. Verkhoturov ◽  
G.N. Verkhoturova ◽  
R.R. Yagudin ◽  
K.V. Danilov ◽  
R.R. Karimov ◽  
...  

The problem of optimizing the life cycle of complex three-dimensional objects in small-scale production is considered. Additive technologies and optimization algorithms for the placement of three-dimensional objects are considered as technologies to solve this problem. Using the multilevel synthesis method can significantly reduce the time for prototyping new products. It should be noted that since several independent parts can be manufactured at the same time, this problem belongs to the class of optimization geometric modelling problems, namely, the problem of three-dimensional irregular placement. An algorithmic solution is proposed for the most complex task - placing 3D objects in a container. The results of the analysis of the effectiveness of the proposed algorithms are discussed.


2020 ◽  
Vol 10 (3) ◽  
pp. 53-59
Author(s):  
L.N. Chernyshov ◽  
E.D. Zakharova

The article discusses already known methods of modeling three-dimensional objects with their subsequent animation. A combined modeling method is proposed, which includes the features of known methods, which reduces the design time of the model, while maintaining its realism.


Algorithms ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 72
Author(s):  
Luca Tonti ◽  
Alessandro Patti

Collision between rigid three-dimensional objects is a very common modelling problem in a wide spectrum of scientific disciplines, including Computer Science and Physics. It spans from realistic animation of polyhedral shapes for computer vision to the description of thermodynamic and dynamic properties in simple and complex fluids. For instance, colloidal particles of especially exotic shapes are commonly modelled as hard-core objects, whose collision test is key to correctly determine their phase and aggregation behaviour. In this work, we propose the Oriented Cuboid Sphere Intersection (OCSI) algorithm to detect collisions between prolate or oblate cuboids and spheres. We investigate OCSI’s performance by bench-marking it against a number of algorithms commonly employed in computer graphics and colloidal science: Quick Rejection First (QRI), Quick Rejection Intertwined (QRF) and a vectorized version of the OBB-sphere collision detection algorithm that explicitly uses SIMD Streaming Extension (SSE) intrinsics, here referred to as SSE-intr. We observed that QRI and QRF significantly depend on the specific cuboid anisotropy and sphere radius, while SSE-intr and OCSI maintain their speed independently of the objects’ geometry. While OCSI and SSE-intr, both based on SIMD parallelization, show excellent and very similar performance, the former provides a more accessible coding and user-friendly implementation as it exploits OpenMP directives for automatic vectorization.


2021 ◽  
pp. 1-38
Author(s):  
Yingya Jia ◽  
Anne S. Tsui ◽  
Xiaoyu Yu

ABSTRACT Optimal or rational decision making is not possible due to informational constraints and limits in computation capability of humans (March & Simon, 1958; March, 1978). This bounded rationality serves as a filtering process in decision making among business executives (Hambrick & Mason, 1984). In this study, we propose the concept of CEO reflective capacity as a behavior-oriented cognitive capability that may overcome to some extent the pervasive limitation of bounded rationality in executive decision-making. Following Hinkin's (1998) method and two executive samples, we developed and validated a three-dimensional measure of CEO reflective capacity. Based on two-wave surveys of CEOs and their executive-subordinates in 213 Chinese small-medium sized firms, we tested and confirmed three hypotheses on how CEO reflective capacity is related to a firm's sustainability performance (including economic, societal, and environmental dimensions) through the mediating mechanisms of strategic decision comprehensiveness and CEO behavioral complexity. We discuss the contribution of this study to the literature on the upper echelons and information processing perspectives. We also identify the implications for future research on strategic leadership and managerial cognition in complex and dynamic contexts.


i-Perception ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 204166952098231
Author(s):  
Masakazu Ohara ◽  
Juno Kim ◽  
Kowa Koida

Perceiving the shape of three-dimensional objects is essential for interacting with them in daily life. If objects are constructed from different materials, can the human visual system accurately estimate their three-dimensional shape? We varied the thickness, motion, opacity, and specularity of globally convex objects rendered in a photorealistic environment. These objects were presented under either dynamic or static viewing condition. Observers rated the overall convexity of these objects along the depth axis. Our results show that observers perceived solid transparent objects as flatter than the same objects rendered with opaque reflectance properties. Regional variation in local root-mean-square image contrast was shown to provide information that is predictive of perceived surface convexity.


2020 ◽  
Vol 26 (6) ◽  
pp. 2927-2955
Author(s):  
Mar Palmeros Parada ◽  
Lotte Asveld ◽  
Patricia Osseweijer ◽  
John Alexander Posada

AbstractBiobased production has been promoted as a sustainable alternative to fossil resources. However, controversies over its impact on sustainability highlight societal concerns, value tensions and uncertainties that have not been taken into account during its development. In this work, the consideration of stakeholders’ values in a biorefinery design project is investigated. Value sensitive design (VSD) is a promising approach to the design of technologies with consideration of stakeholders’ values, however, it is not directly applicable for complex systems like biorefineries. Therefore, some elements of VSD, such as the identification of relevant values and their connection to a technology’s features, are brought into biorefinery design practice. Midstream modulation (MM), an approach to promoting the consideration of societal aspects during research and development activities, is applied to promote reflection and value considerations during the design decision making. As result, it is shown that MM interventions during the design process led to new design alternatives in support of stakeholders' values, and allowed to recognize and respond to emerging value tensions within the scope of the project. In this way, the present work shows a novel approach for the technical investigation of VSD, especially for biorefineries. Also, based on this work it is argued that not only reflection, but also flexibility and openness are important for the application of VSD in the context of biorefinery design.


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