Cable-Driven Actuation for Highly Dynamic Robotic Systems

This paper presents design and experimental evaluations of an articulated robotic limb called Capler-Leg. The key element of Capler-Leg is its single-stage cable-pulley transmission combined with a high-gap radius motor. Our cable-pulley system is designed to be as light-weight as possible and to additionally serve as the primary cooling element, thus significantly increasing the power density and efficiency of the overall system. The total weight of active elements on the leg, i.e. the stators and the rotors, contribute more than 60% of the total leg weight, which is an order of magnitude higher than most existing robots. The resulting robotic leg has low inertia, high torque transparency, low manufacturing cost, no backlash, and a low number of parts. Capler-Leg system itself, serves as an experimental setup for evaluating the proposed cable- pulley design in terms of robustness and efficiency. A continuous jump experiment shows a remarkable 96.5 % recuperation rate, measured at the battery output. This means that almost all the mechanical energy output used during push-off returned back to the battery during touch-down

Two worlds:design relativity in the complex world

This paper proposes that there could be ‘relative’ meanings of design in organizations, according to the different national cultures in which the organizations predominantly reside, due to the different organizational vocabulary that is used in the design of a ‘complex product’. The paper suggests that under complex conditions, different meanings of design according to national cultures could influence, not only the development of an organization, but also the design of these complex products. The author contends that much research on the meaning of design and its use in design-led innovation takes a Western perspective; however this paper discusses how different national cultures influence the construction of product design and how different national cultures could influence the meaning of design in complex organizations. This is achieved by examining a case study in Samsung, which has been involved in a global dispute regarding its product design patents with Apple. This paper explores how this lens might help to understand how design-led innovation is viewed differently and how the resulting product design is influenced by national and derived organizational cultures

Performance Evaluation of Wind Power Systems Based on Production Economics Theory

The research in this dissertation addresses the issues in the performance evaluation of wind power systems under commercially operating circumstances. Such an evaluation is critical to a wide range of decisions including operations and maintenance planning, reliability assessment, asset procurement, and system designs. However, accurate evaluation is excessively challenging due to the unknown causal relationship between wind input and power output, the dependency of power output on numerous uncontrollable factors, and the high level of uncertainty observed in power output. While addressing these challenges, we develop a new performance measure based on production economics theories and propose effective methodologies for evaluating the performance of wind power systems. By doing so, this dissertation study aims to improve the practice of performance evaluation in the wind industry. We define an efficiency metric analogous to productive efficiency, which requires estimating a performance benchmark, i.e., the performance referring to 100% efficiency. For the performance benchmark, we develop a stochastic nonparametric estimator maintaining S-shape, the typical shape observed in the wind input-power output relationship. When applying the efficiency metric for comparing performance under different scenarios, other environmental factors need to be controlled for, as their difference could produce a difference in power output. We devise a covariate density matching method that selects subsets of data for which probability densities of the environmental factors are comparable; evaluating only these subsets, then, ensures a fair comparison. We further investigate wake situations in which the operation of a turbine could cause a significant power deficit on its neighboring turbines. In the presence of the performance benchmark introduced earlier, ii we can model the power deficit as a non-negative term subtracted from the benchmark. Based on this model setup, we develop a spline model with a non-negativity constraint imposed for characterizing such a wake effect. When each of the proposed methods is applied to operational wind data, the respective results demonstrate that each of the methods outperforms its competitive alternatives in terms of estimation and/or prediction accuracy. This suggests that the methods can reduce the unaccounted uncertainty in power output and thus provide better insight into the performance of wind power systems

Understanding of large Far Eastern organizational cultures in approaches to new product development process:designing versus controlling

This paper explores how approaches to new product design can differ nationally when examining large organizational cultures between the East and the West, especially looking at different approaches in the context of ‘openness’. Currently, approaches to new product development in digital landscape have shifted to evolutionary perspectives, which embrace an ‘open’ context in the design process – ‘designing’, rather than single hierarchical and closed strategy for efficiency- ‘controlling’. This paper highlights that NPD process in Far Eastern Asia’s organizational cultures have been underlined in single hierarchical organizational cultures resulting in engineered product design under ‘controlling’, rather than ‘designing’

Ambidexterity of design management in different approaches to digital design:review of organizational attitudes in the East and the West in new product development process

Currently, there is growing interest in shaping a digital ecosystem that embraces holistic design approaches. In the digital realm, organizational approaches to managing design are required to shift to ‘designing’ towards holistic digital design, rather than ‘design’ for a completed output. Within this context, this paper reviews how organizational cultures can impact the development of holistic product design in competitive digital landscapes. This is done by investigating different organizational cultures as reflected in large Eastern and Western organizations’ approaches to managing design in the new product development (NPD) process. Despite significances of ‘designing’ this study discovered ambidexterity aspects of digital design in NPD projects, from international organizational perspectives. The findings offer key understandings that can explain the dilemmatic relations by examining key differences of design priorities in new digital product development in the East and the West: namely the East focusing on ‘design output’; whereas the West expecting ‘design outcomes’. Based on this we propose two major scenarios that represent the different approaches to managing design by organizational cultures