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    <title>Transport Research International Documentation (TRID)</title>
    <link>https://trid.trb.org/</link>
    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <language>en-us</language>
    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
    <docs>http://blogs.law.harvard.edu/tech/rss</docs>
    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
    <image>
      <title>Transport Research International Documentation (TRID)</title>
      <url>https://trid.trb.org/Images/PageHeader-wTitle.jpg</url>
      <link>https://trid.trb.org/</link>
    </image>
    <item>
      <title>Integrated Fully-Over Actuated Multielectromagnet Collaborative Nonlinear Controller for Maglev Microgravity Experimental Capsule</title>
      <link>https://trid.trb.org/View/2603978</link>
      <description><![CDATA[The Maglev microgravity experimental capsule (MMEC) possesses advantages such as high precision, low cost, and strong controllability, making it as a crucial scientific instrument for future ground-based microgravity experiments. However, the intricate coupling and collaboration among multiple electromagnets for levitation in MMEC are unexplored, and the impact of the varying number of electromagnets on the control system, along with the significant mass changes and interference from the separation/combination of internal and external capsules in the microgravity phase, pose challenges to its microgravity performance improvement. To address these issues, this study proposes an integrated fully over actuated multielectromagnet collaborative nonlinear (MCN) controller. By leveraging the established comprehensive state-extended nonlinear model of MMEC and analyzing the relationships among multiple electromagnets, this controller enables effective control of fully actuated and over-actuated systems, addressing the challenge posed by the variable number of electromagnets resulting from payload fluctuations. A stability analysis for capsule separation and combination in the microgravity phase is also carried out to overcome the issues of sudden mass changes and external interference. Experiments on a ground-based platform verify the effectiveness of the proposed method, providing a theoretical basis and practical experience for enhancing MMEC’s microgravity performance.]]></description>
      <pubDate>Tue, 02 Dec 2025 16:09:26 GMT</pubDate>
      <guid>https://trid.trb.org/View/2603978</guid>
    </item>
    <item>
      <title>An Integrated Fault-Tolerant Control for Electric Actuation System in More Electric Aircraft</title>
      <link>https://trid.trb.org/View/2603936</link>
      <description><![CDATA[A more electric aircraft (MEA) is an innovative aircraft design that integrates secondary onboard energy sources into an electric system, offering significant advantages in fuel efficiency, reliability, and maintainability. A key enabler of the MEA concept is the development of advanced electric actuation systems, which are critical for optimizing aircraft performance. However, these systems frequently face challenges related to uncertainties and actuator failures in complex operational environments. To address these issues, this article proposes an integrated fault-tolerant control (FTC) approach that combines dynamic modeling, uncertainty analysis, fault compensation, and nonlinear robust control design. Specifically, a robust FTC strategy is developed to mitigate actuator faults and system uncertainties. The proposed approach is validated through theoretical analysis and numerical–hydraulic cosimulations, demonstrating its effectiveness in improving system stability and fault resilience. Cosimulation results confirm that the method significantly enhances control performance under multiple uncertainties, providing a practical solution for MEA actuation systems.]]></description>
      <pubDate>Thu, 20 Nov 2025 17:07:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/2603936</guid>
    </item>
    <item>
      <title>Disturbance rejection control for underactuated surface vessels with input saturation</title>
      <link>https://trid.trb.org/View/2570460</link>
      <description><![CDATA[This paper presents a disturbance rejection control strategy for underactuated surface vessels (USVs) under input saturation. The proposed disturbance observer generates real-time estimates of low-frequency disturbances, which effectively compensate for the lumped disturbances encountered by the USV in dynamic environments. A theoretical analysis of the proposed observer is conducted from a complex frequency domain perspective, which reveals its response characteristics across varying frequencies. This analysis framework circumvents the stringent assumptions regarding the differentiability of disturbance signals imposed by traditional methods, which reduces the conservativeness of the approach. Furthermore, a disturbance rejection strategy is developed based on the proposed disturbance observer, which enhances the robustness of the designed USV controller. The controller incorporates an auxiliary dynamic system to ensure stable control of the USV under input saturation. Lyapunov stability analysis is employed to prove the stability of the closed-loop control system, which provides theoretical support for achieving robust control performance. Experimental results demonstrate that the proposed disturbance rejection control strategy significantly enhances control performance.]]></description>
      <pubDate>Wed, 27 Aug 2025 16:44:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/2570460</guid>
    </item>
    <item>
      <title>Robust performance comparison of PMSM for flight control applications in more electric aircraft</title>
      <link>https://trid.trb.org/View/2216657</link>
      <description><![CDATA[This paper describes a robust performance comparison of flight control actuation controllers based on a permanent magnet synchronous motor (PMSM) in more electric aircraft (MEA). Recently, the PMSM has become a favorite for the flight control applications of more electric aircraft (MEA) due to their improved efficiency, higher torque, less noise, and higher reliability as compared to their counterparts. Thus, advanced nonlinear control techniques offer even better performance for the control of PMSM as noticed in this research. In this paper, three nonlinear approaches i.e. Feedback Linearization Control (FBL) through the cancellation of the non-linearity of the system, the stabilization of the system via Backstepping Control (BSC) using the Lyapunov candidate function as well as the robust performance with chattering minimization by applying the continuous approximation based Sliding Mode Control (SMC) are compared with generalized Field-Oriented Controller (FOC). The comparison of FOC, FBL, BSC and SMC shows that the nonlinear controllers perform well under varying aerodynamic loads during flight. However, the performance of the sliding mode control is found superior as compared to the other three controllers in terms of better performance characteristics e.g. response time, steady-state error etc. as well as the control robustness in the presence of the uncertain parameters of the PMSM model and variable load torque acting as a disturbance. In essence, the peak of the tolerance band is less than 20% for all nonlinear and FOC controller, while it is less than 5% for SMC. Steady state error for the SMC is least (0.01%) as compared to other three controllers. Moreover, the SMC controller is able to withstand 50% parameter variation and loading torque of 10 N.m without significant changes in performance. Six simulation scenarios are used to analyze the performance and robustness which depict that the sliding mode controller performs well in terms of the desired performance for MEA application.]]></description>
      <pubDate>Mon, 01 Apr 2024 09:03:10 GMT</pubDate>
      <guid>https://trid.trb.org/View/2216657</guid>
    </item>
    <item>
      <title>Iterative Learning for Laboratory Electro-Hydraulic Fully Flexible
                    Valve Actuation System Transient Control</title>
      <link>https://trid.trb.org/View/2341672</link>
      <description><![CDATA[
                
                Fully flexible valve actuation (FFVA) is a key enabling technology of internal
                    engine combustion research and development. Two laboratory electro-hydraulic
                    FFVA systems have been developed and implemented in R&D test cells. These
                    FFVA systems were designed using repetitive control (RC), which is based on
                    internal model principle (IMP), for constant engine speed operation. With the
                    engine operating in a steady-state condition, the valve profile input is
                    periodic. This can be accommodated by a repetitive controller, which provides
                    the function of flexible control to step changes in valve lift, valve opening
                    duration, and cam phase angle position.
                During engine speed transients, as the valve reference trajectory becomes
                    aperiodic in the time domain, the controllers based on the linear time invariant
                    (LTI) IMP, such as RC, are no longer applicable. Engine speed transient control
                    is a desired function to engine research and other similar applications, such as
                    motor control. Several investigations are reported with limited results because
                    of the assumption of IMP and periodic input.
                This article presents the control design and verification of the iterative
                    learning control (ILC) algorithm for the laboratory electro-hydraulic FFVA
                    system. This algorithm tracks valve lift profiles under steady-state and
                    transient operation. A dynamic model of the plant was obtained from experimental
                    data to design and verify the effectiveness and robustness of this approach. The
                    simple structure of the ILC in implementation and low cost in computation are
                    crucial benefits to recommend the ILC. It is not an IMP-based approach, and its
                    structure does not depend on the system input. Therefore, it has higher
                    robustness to perturbation and modeling errors than other control methods for
                    repetitive valve lift profile tracking tasks.
            ]]></description>
      <pubDate>Mon, 26 Feb 2024 08:52:14 GMT</pubDate>
      <guid>https://trid.trb.org/View/2341672</guid>
    </item>
    <item>
      <title>Investigate the In-Vehicle Healthcare System Design Opportunities: Findings from a Co-design Study</title>
      <link>https://trid.trb.org/View/2112990</link>
      <description><![CDATA[Many people spend a long time in vehicles in their daily commute, and they want their health condition to be taken care of during the journey. In line with this need, the advancement of smart technologies brings possibilities for ubiquitous healthcare. This work intends to explore users’ expectations regarding an in-vehicle healthcare system (IVHS) and guide the development of relevant technologies. Four co-design workshops were organized with sixteen participants with diverse professional backgrounds. Over two hundred ideas were generated and categorized into seven groups, indicating seven promising perspectives in developing an IVHS. Furthermore, a conceptual framework was proposed based on the ideas collected from the workshops. The framework organized the expected functions of an IVHS into three groups, namely data collection, communication, and actuation. In combination with the literature review about relevant technologies, the framework pointed out some future research directions.]]></description>
      <pubDate>Sat, 12 Aug 2023 16:54:24 GMT</pubDate>
      <guid>https://trid.trb.org/View/2112990</guid>
    </item>
    <item>
      <title>Augmented model-based dynamic positioning predictive control for underactuated unmanned surface vessels with dual-propellers</title>
      <link>https://trid.trb.org/View/2077639</link>
      <description><![CDATA[The dynamic positioning control for underactuated unmanned surface vessel (u-USV) is difficult but urgently needed. This paper aims to propose an effective dynamic positioning controller for u-USV. The accuracy of the internal dynamics of u-USV is improved by designing an augmented model (AM) based on a residual neural network. After that, an AM-based finite-time observer (AM-FTO) is designed. The disturbance observed by the AM-FTO is mainly the environmental disturbance, not the original composite disturbance anymore. Further, the direction of the environmental disturbance can be estimated. Taking the direction as the desired heading, a dynamic positioning controller is designed for u-USV based on the nonlinear model predictive control (NMPC) method. Simulations and experiments show that the proposed method can track the internal dynamics of u-USV with high accuracy. Additionally, the designed dynamic positioning controller has better performance than the existing popular NMPC method.]]></description>
      <pubDate>Fri, 16 Dec 2022 09:41:08 GMT</pubDate>
      <guid>https://trid.trb.org/View/2077639</guid>
    </item>
    <item>
      <title>The Preliminary Design of a Direct Actuation for CNG Pressure Regulator Low-Pressure Stage Control</title>
      <link>https://trid.trb.org/View/1813734</link>
      <description><![CDATA[This paper focuses on the preliminary design of a proportional solenoid aimed at controlling the low pressure stage of a two stage pressure regulator for CNG applications. In particular, the dynamic performance of a two stage pressure regulator is firstly studied in the whole operational field of a four stroke, four cylinder spark ignition engine, equipped with a simplified low-pressure Common Rail type collector serving four PWM actuated single stage injectors. Then, with the aim of developing an electro-magnetic direct actuation, the dynamic performance of the second stage needle is adopted to drive the design of a spires type, cylindrical coil proportional solenoid. In particular, both the steady and the transients steps needed to complete the preliminary design are highlighted, and the influence of some relevant design parameters (such as the coil geometry and the air gap) on the actuation characteristics are evidenced. Finally, the proportional solenoid is introduced into a standard electro-magnetic control circuit, and its driving capabilities, its dynamic performance and its limit of applications are determined for different actual operating conditions of the second stage needle.]]></description>
      <pubDate>Mon, 26 Sep 2022 11:26:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/1813734</guid>
    </item>
    <item>
      <title>Application of a Fully Flexible Electro-Hydraulic Camless System to a Research SI Engine</title>
      <link>https://trid.trb.org/View/1819240</link>
      <description><![CDATA[This paper presents the further development of an electro-hydraulic camless valve actuation system for internal combustion engines. The system (Hydraulic Valve Control - HVC) is an open loop device for engine valve fully flexible camless actuation. Valve timing and duration are controlled by a pilot stage governed by a solenoid, fast-acting, three-way valve. Valve lift is controlled by varying the oil pressure of the power stage. The system exploits an energy recovery working principle that plays a significant role in reducing the power demand of the whole valve train. In the present paper a new HVC actuator design is presented and its performances in terms of valve lift profile, repeatability and landing are discussed. Experimental data obtained by the application of the HVC system to a motored, single-cylinder research engine have been used to support the numerical evaluation of the potentialities of non-conventional valve actuation in engine part-load operation. This efficiency analysis was carried out including both thermodynamic benefits and the corresponding energy requirements of the used valve actuation system.]]></description>
      <pubDate>Thu, 21 Jul 2022 13:39:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1819240</guid>
    </item>
    <item>
      <title>Adaptive synchronization with disturbance rejection for under-actuated ships with disturbances under thruster saturation</title>
      <link>https://trid.trb.org/View/1950348</link>
      <description><![CDATA[An adaptive synchronization control scheme with the disturbance estimation and rejection is proposed for the under-actuated ships with unknown time-varying disturbances under thruster saturation effects without leader ship’s velocities. The unknown time-varying disturbances are described as the sinusoidal disturbances whose amplitudes, frequencies and phases are uncertain. The disturbances are expressed by using an unknown parametric exogenous system which is converted into a canonical model with the disturbances as inputs. A disturbance filter is constructed to estimate the state vector in the canonical model such that the disturbances are represented by the parametric equations with exponentially decaying errors. The main highlights lie in that the anti-disturbance problem is transformed into the adaptive control problem based on parametric disturbance representations. This enables that the additional control filters are constructed to generate the filtered signals of the control deviations to on-line correct feedback control errors such that the adaptive disturbance rejection control would be workable under thruster saturation effects. The proposed adaptive synchronization scheme achieves the disturbance rejection and the thruster saturation attenuation simultaneously. Simulations with comparisons demonstrate the effectiveness and the superiority of the control scheme.]]></description>
      <pubDate>Wed, 25 May 2022 09:35:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1950348</guid>
    </item>
    <item>
      <title>Actuator Fault Detection for Unmanned Ground Vehicles Considering Friction Coefficients</title>
      <link>https://trid.trb.org/View/1907090</link>
      <description><![CDATA[This paper proposes an actuator fault detection method for unmanned ground vehicle (UGV) dynamics with four mecanum wheels. The actuator fault detection method is based on unknown input observers for linear parameter varying systems. The technical novelty of current work compared to similar work in the literature is that wheel frictions are directly taken into account in the dynamics of UGV, and unknown input observers are developed accordingly. Including the wheel friction, the vehicle dynamics are in the form of linear parameter varying systems. Friction estimation is also discussed in this work, and the effect of friction mismatch was quantitatively investigated by simulations. The effectiveness of proposed method was evaluated under various operation scenarios of the UGV.]]></description>
      <pubDate>Mon, 31 Jan 2022 16:49:16 GMT</pubDate>
      <guid>https://trid.trb.org/View/1907090</guid>
    </item>
    <item>
      <title>Improved ELOS based path following control for underactuated surface vessels with roll constraint</title>
      <link>https://trid.trb.org/View/1903021</link>
      <description><![CDATA[This study aims to the path following control of underactuated surface vessels with an improved extended state observer based line-of-sight (ELOS). The large roll motion and nonzero drift angle can affect the guidance law and the course tracking accuracy in rough waves, the two factors should be considered when the path following control system is designed. The robustness of the tracking control system is enhanced by handling the system dynamic uncertainty and external random disturbances. First, the roll motion based track error dynamics are established, then a reduced order extended state observer is applied to estimate the time varying drift angle, and the adaptive heading guidance law is proposed. Finally, a robust adaptive heading control law is developed by combining dynamic surface control, sliding mode control and backstepping techniques. The ELOS based path following control methodology can ensure that all estimation and track errors are uniformly ultimately bounded. Simulations were used to illustrate the effectiveness of the proposed controller by comparing it with sliding mode control.]]></description>
      <pubDate>Tue, 25 Jan 2022 09:50:46 GMT</pubDate>
      <guid>https://trid.trb.org/View/1903021</guid>
    </item>
    <item>
      <title>Review of Electric Machines in More-/Hybrid-/Turbo-Electric Aircraft</title>
      <link>https://trid.trb.org/View/1883061</link>
      <description><![CDATA[Aircraft electrification is currently the best alternative to address the rising demand for more air transportation and deal with anticipated economic and environmental impacts. Although the all-electric-aircraft (AEA) concept is not yet a feasible solution, the more-electric aircraft (MEA) is gaining significant attention. Electrical systems either partially or entirely replace the large and inefficient hydraulic, pneumatic, and mechanical conventional aircraft actuating systems. The upgrade could also encompass the propulsion system, as in hybrid- and turbo-electric aircraft. This upgrade reduces the aircraft weight, reduces the usage of pollutant fluids, increases fuel efficiency, reduces carbon emissions, and increases aircraft controllability and reliability. This article reviews various application areas of electric machines in electrified aircraft, such as actuation, taxiing, propulsion, and generation. Moreover, it reviews the main types of currently/to be utilized electric machines and the critically required specifications. Finally, a comparison between the different considered machines and potential future research is discussed.]]></description>
      <pubDate>Mon, 15 Nov 2021 09:24:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/1883061</guid>
    </item>
    <item>
      <title>DVSL guidance-based composite neural path following control for underactuated cable-laying vessels using event-triggered inputs</title>
      <link>https://trid.trb.org/View/1877979</link>
      <description><![CDATA[In this note, the path following issue of underactuated cable-laying vessels is addressed from two aspects, i.e., guidance and control. By exploiting the hierarchical design, a so-called dual virtual ships layered (DVSL) guidance algorithm is proposed with two reference path generators. In the first guidance layer, the logical virtual ship (LVS) is used to programme the setpoints-based reference path for cables. Based on the cable-related geometrical derivation, the corresponding ship’s reference path can be obtained in the second layer, and its smoothness can be guaranteed by the adaptive virtual ship (AVS). For the control part, a novel composite neural event-triggered control algorithm is developed by taking the main engine revolution and the rudder as actual control inputs, which are characterized by the practical measurability and the aperiodic update. The radial basis function neural networks (RBF-NNs) are employed to deal with the model uncertainty, and the approximation performance is improved with the aid of the serial-parallel estimation model (SPEM). By fusing the robust neural damping technique, only two adaptive parameters require to be updated, which leads to a simpler controller with less computation burden. Besides, the inputs-dominated event-triggered mechanism is introduced to release the communication traffic in the controller-to-actuator channel. Through the Lyapunov stability analysis, all signals in the closed-loop system are guaranteed to be semi-global uniformly ultimately bounded (SGUUB), and the existence of minimum inter-event time is proved. Finally, three simulation experiments are conducted to illustrate the effectiveness and the superiority of proposed algorithm.]]></description>
      <pubDate>Mon, 20 Sep 2021 14:52:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1877979</guid>
    </item>
    <item>
      <title>Air-System and Variable Valve Actuation Recipe for High Load Gasoline Compression Ignition Operation in a Heavy-Duty Diesel Engine</title>
      <link>https://trid.trb.org/View/1847361</link>
      <description><![CDATA[Gasoline compression ignition (GCI) offers improved efficiency by harnessing gasoline’s low reactivity to induce an extended ignition delay that promotes partial premixing of air and fuel before combustion occurs. However, enabling GCI across the full engine operating load map poses several challenges. At high load, due to the elevated pressures and temperatures of the charge mixture, the ignition delay time shrinks, leading to diminished GCI efficiency benefits. At low load, insufficient temperatures and pressures can lead to combustion instability. Variable valve actuation offers a practical solution to these challenges by enabling effective compression ratio (ECR) control. In this paper, the effects of variable intake valve closings were investigated for high load operations in a prototype heavy-duty GCI engine, using a research octane number 93 gasoline fuel. The study focused on the 50% (B50) and the 75% (B75) load conditions at 1375 RPM. Both late intake valve closing and early intake valve closing strategies were analyzed as a measure to reduce the effective compression ratio. Reducing ECR, enabled by variable intake valve closing, not only provided control over in-cylinder temperature and pressure, but also led to a reduced in-cylinder trapped charge-mass that compromised engine load. This, in turn, led to higher boost pressure requirements. Subsequently, a detailed air-handling system analysis was conducted to identify a turbocharger capable of delivering the high boost pressure demands for high load operations at reduced ECR. Three turbocharger systems were evaluated: (a) a stock 1-Stage turbocharger, (b) an available production 2-Stage turbocharger and (c) a prototype high-efficiency 1-Stage variable geometry turbocharger. For the analysis, an approach that closely coupled 1-D engine simulations with a 3-D CFD combustion model was used. At B50 and B75, reducing the ECR to 13 and 12, via variable intake valve closing, resulted in 1% and 1.5% increases in gross indicated efficiency, respectively. As a result, the boost pressure demand rose by approximately 0.47 bar at B50 and 0.65 bar at B75, to compensate the loss in trapped in-cylinder charge mass. Against the elevated boost pressure demand, the stock turbocharger, due to inadequate combined efficiencies, struggled to deliver the boost pressure targets. The production two-Stage turbocharger system successfully delivered the boost targets, at the expense of relatively high pumping losses. Finally, the prototype 1-Stage variable geometry turbocharger delivered the best combined turbocharger efficiencies at B50 and B75, resulting in the lowest pumping losses and the best brake efficiencies. The combined effects of the prototype turbocharger system, high pressure exhaust gas recirculation and variable valve actuation delivered a viable recipe for high load GCI operation in heavy-duty engines.]]></description>
      <pubDate>Thu, 29 Jul 2021 11:58:55 GMT</pubDate>
      <guid>https://trid.trb.org/View/1847361</guid>
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