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In this article, a novel interval type-2 Takagi–Sugeno fuzzy $c$ -regression modeling method with a modified distance definition is proposed. The modified distance definition is developed to describe the distance between each data point and the local type-2 fuzzy model. To improve the robustness of the proposed identification method, a modified objective function is presented. In addition, different from most previous studies that require numerous free parameters to be determined, an interval type-2 fuzzy $c$ -regression model is developed to reduce the number of such free parameters. Furthermore, an improved ratio between the upper and lower weights is proposed based on the upper and lower membership function with each input data, and the ordinary least-squares method is adopted to establish the type-2 fuzzy model. The Box–Jenkins model and two numerical models are given to illustrate the effectiveness and robustness of the proposed results. [ABSTRACT FROM AUTHOR]

In this article, we design the controller for multiagent systems such that the agents with nonlinear dynamics can form into arbitrarily given shapes, rotate around the formation centroid at the given angular velocity, track the reference trajectory, and dynamically adjust the formation for obstacle avoidance. In addition, the proposed design ensures that the agents can be positioned with a specified order in the formation. We propose an extended model for the system to facilitate the design. To deal with the order issue, we introduce the phase weighting parameter and the phase penalty flow exchange mechanism such that the agent’s position can be adjusted to the desired order. With the aid of the proposed tools, we first design the formation controller for MAS with a planar unicycle model and then extend it to the three-dimensional space. The controller is designed based on information from the neighbors and is measured in the agents’ local reference frame. Moreover, unlike most of the existing works, the initial conditions are not restricted in our approach. Finally, system stability is proved via the Lyapunov theorem and several simulation examples are provided to validate our results. [ABSTRACT FROM AUTHOR]

This work evaluated several electrode designs in a capacitive tactile sensor (CTS) to provide an optimized solution that shows the maximized sensitivity in shear force detection. In addition to shear angle derivation procedure, identical overlapping areas between the paired electrodes in capacitors were assigned for fair comparison on detection sensitivity of normal force. The theoretical calculation, numerical simulation, practical fabrication, analysis, and discussion were comprehensively conducted in this work with a typical CTS that showed square electrodes as a reference. Results indicated that when the number of legs in a polygon electrode is small, the detection sensitivity in shear force application is high. Furthermore, because the operating principle was unaltered, all designs exhibited compatible detection capability on shear angle in terms of resolution and accuracy. Although only two extreme cases of CTSs with triangular and circular electrodes were demonstrated as proofs-of-concept in this work, the universal solution is also eligible to other designs with polygon electrodes. [ABSTRACT FROM AUTHOR]

Four factors that contribute to shear angle derivation tolerances in a vertically stacked capacitive tactile sensor with the highest detection sensitivity were thoroughly studied. The fringe effect that appears in a sensing array was found as an environmental factor contributing to the tolerance (0.031°); the torsional deformation that appears in the electrode was found as a structural factor contributing to the tolerance (0.011°); the torque-induced deformation generated from the bump was found as an applicational factor contributing to the tolerance (0.087°); and the asymmetrical stress distribution in the elastomeric dielectric was found as an operational factor contributing to the tolerance (− 0.968°). The effects of these factors were neglected in previous related studies. This paper provides a calibration solution for each case. Additionally, tolerances projected from the contributions of these factors under different conditions are provided with high coefficients of determination based on corresponding regressions. This paper provides scientific and quantified tolerances for verifying the derived shear angle when accurate detection is desired. [ABSTRACT FROM AUTHOR]

In this study, a novel response acquisition method was proposed and verified in a capacitive tactile sensing array, which collected signals from shared capacitors between two adjacent sensing units. In the proposed design, the electrodes of a capacitor exhibited intentional misalignments in the xy-plane and four types of misalignments existed in the array. The tactile sensing array was then numerically evaluated, fabricated, and demonstrated. With the proposed method, the previously undetectable normal force was resolvable with noticeable (at least 225%) spatial resolution enhancement. Because the composition of the sensing array, number of capacitors in the array, and electrode dimensions in the capacitors were all unaltered from the conventional design, high detection sensitivities (on average 3.261 pF/ N for the normal force) were obtained. Additionally, although the four types of sensing unit required four corresponding algorithms to derive the shear angles, results proved that the supportiveness was remained and accuracy was unaltered compared to existing similar works. [ABSTRACT FROM AUTHOR]

In this study, a capacitive tactile sensor (CTS) that simultaneously supports high detection sensitivity and high spatial resolution with a hollow dielectric structure is reported. By vertically stacking two capacitors with intentionally misaligned electrodes among the capacitors, not only the normal and shear force but also the shear angle can be detected. A comprehensive fabrication procedure that advanced the existing solutions was developed in addition to its theoretical design and numerical evaluation. Results indicated that the proposed hollow CTS outperformed the referential solid CTS in detection sensitivity for both the normal (on average 31.660 pF/N under 0.5 N) and shear force (at least 5.61 times enhancement under 1.5 N) applications. The results also proved comparable shear angle detection accuracy to previously existing CTS. Additionally, the periodical variation of sensitivity enhancement along the shear angle was found and analyzed for the first time, which provided design guidance for the arrangement of the electrodes in the CTS regardless of its dielectric structure. [ABSTRACT FROM AUTHOR]

In this investigation, we propose and demonstrate an integrated vertical-cavity surface-emitting laser (VCSEL) and blue light emitting diode (LED) based visible light communication (VLC) system by using the decode-and-forward (DF) relay scheme indoors. The 682 nm visible VCSEL can reach 3 Gbit/s on-off keying (OOK) modulation rate for 4 m free space transmission by applying 1.25 GHz bandwidth PIN photodiode (PD). Then, the VLCVCSEL signal connects to multiple blue LEDs for broadcasting VLCLED traffic in parallel. Therefore, the maximum VLCLED rates of 775, 700, and 600 Mbit/s are obtained at the free space transmission lengths of 2, 3, and 4 m, respectively within the forward error correction (FEC) target under 4 m VLC transmission at the low detected power of 15 μW. In addition, the number of LEDs used in the DF relay VLC system depends on the practical requirement of VLCLED rate and traffic length indoors. [ABSTRACT FROM AUTHOR]

In this study, stoppers were designed and allocated in a planar four-capacitor (P4C) sensing unit for modulating capacitive tactile sensor (CTS) characteristics. The stoppers deterred the structural deformation of the CTS when applied with normal forces, realizing a three-stage operation: high detection sensitivity, wide dynamic range, and saturation. Comprehensive studies including theoretical design, numerical evaluation, demonstrator fabrication, experimental analysis, and a technical discussion were conducted. The proposed CTS achieved 0.901 pF/N sensitivity, enhanced dynamic range by 235.3%, and supported 2.1 N detection in the first, second, and third stages under normal force applications, respectively. With the CTS characteristics resulting from varying stopper locations, a relationship between the capacitive response and applied force is established to support typical P4C CTSs in arbitrary dimensions. In addition, systematic tolerance is studied to explain detection accuracy for the first time. The proposed CTS provides operation flexibility in normal force detections, and unaltered supportiveness on shear force and its angle detections, compared with typical CTSs. [ABSTRACT FROM AUTHOR]

Fluctuated penetration of electric vehicle (EV) loads and production capacities from distributed energy resource (DER) bring large impacts to power systems. To smooth fluctuations, financial incentives have to be maximized for customers controlling their consumption patterns. A fair demand response with electric vehicles (F-DREVs) is proposed for the cloud-based energy management service. Customers with EV, DER, storage and multiple loads form communities and obtain optimal choices (electricity usage and trading) from F-DREV. F-DREV aims to maximize incentives by minimizing global cost for each community within the given time period, and smooth fluctuations. In order to attract customers to actively participate, we propose the fairness as “customers with higher participation level can reduce their individual cost more than those with lower participation level within the same community,” which is attainable by customizing trading prices. A binary linear programming model is formulated, and performances are evaluated in experiments. [ABSTRACT FROM PUBLISHER]

The increasing penetration of renewable energy has become a critical issue in recent years. The future power system is foreseen to depend on distributed energy resource (DER) excessively for continuous load support. Yet, DER providers are also facing limited choices in their produced renewable energy. Massive information and complicated cooperation emerging from involvers intensify issues in terms of efficiency, reliability, and scalability. In this paper, a cloud-based framework is proposed to provide a customer-oriented energy management as a service (EMaaS) for green communities, which are formed as virtual retail electricity providers (REPs) by involved DERs providers. It can be adopted by existing REPs or utilities. For each green community, the multiperiod global cost is minimized to promote renewable energy, and renewable energy consumption is stabilized to enhance integration. A solvable linear programming model is formulated for EMaaS. The case studies results reveal the proposed EMaaS retains satisfactory performances. [ABSTRACT FROM PUBLISHER]

Our objective is to allocate power to air conditioners in a fair manner when the demand for power exceeds the supply or when the load in regions of the network exceeds the capacity of the transmission links. This is an alternative to the current practice of brown outs or black outs and to the proposed pricing mechanisms that curtail demand. The procedure operates on a smart grid. Customers request a thermostat setting for their air conditioner, and the power company sets the thermostat to fairly allocate the available power. We describe 1) simple techniques to predict changes in power consumption for modest changes in the setting of a thermostat in each residence, 2) algorithms to apply two fairness metrics used in communications networks to power allocation, 3) an algorithm to control power to different parts of a capacity constrained distribution network, and 4) a practical procedure to apply these techniques. [ABSTRACT FROM PUBLISHER]