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WOA-tuned supertwisted synergetic control of multipurpose on-board charger for G2V/V2G/V2V operational modes of electric vehicles 针对电动汽车的 G2V/V2G/V2V 运行模式,对多功能车载充电器进行 WOA 调谐的超扭曲协同控制
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-22 DOI: 10.1016/j.conengprac.2024.106136
Hafiz Mian Muhammad Adil, Hassan Abbas Khan
On-board chargers within electric vehicles (EVs) must efficiently manage grid-to-vehicle (G2V), vehicle-to-grid (V2G), and vehicle-to-vehicle (V2V) modes for sustainable EV operation. This paper introduces a modified hybrid nonlinear control approach that utilizes the whale optimization algorithm-tuned supertwisted synergetic (WOA-ST-syn) technique for a multipurpose on-board charger (MP-OBC). The whale optimization algorithm(WOA) adjusts the parameters of supertwisted synergetic controller using the integral time absolute error, reducing the need for exhaustive trial-and-error adjustments. The controller employs the state space model of a two-stage on-board electric vehicle charging system, ensuring stability through the Lyapunov stability criterion. Simulations in MATLAB/Simulink evaluate the performance of the proposed controller across various operational modes, testing robustness against varying load currents and mode-switching conditions. Results indicate significant improvements over state-of-the-art nonlinear controllers, with minimal chattering, shortest rise time (0.0007 s for AC-DC, 1.5520 s for DC-DC), fastest settling time (0.0447 s for AC-DC, 2.0550 s for DC-DC), and minimal steady-state error (0.0010% for AC-DC, 0.0004% for DC-DC). Controller Hardware-in-the-Loop (C-HIL) experiments were also performed to confirm the real-time applicability of the controller.
电动汽车(EV)的车载充电器必须有效管理电网到车辆(G2V)、车辆到电网(V2G)和车辆到车辆(V2V)模式,以实现电动汽车的可持续运行。本文针对多功能车载充电器(MP-OBC)介绍了一种改进的混合非线性控制方法,该方法利用了鲸鱼优化算法调谐超扭曲协同(WOA-ST-syn)技术。鲸鱼优化算法(WOA)利用积分时间绝对误差来调整超扭曲协同控制器的参数,从而减少了反复试错调整的需要。控制器采用两级车载电动汽车充电系统的状态空间模型,通过 Lyapunov 稳定性准则确保稳定性。在 MATLAB/Simulink 中进行的仿真评估了拟议控制器在各种运行模式下的性能,测试了其在不同负载电流和模式切换条件下的稳健性。结果表明,与最先进的非线性控制器相比,该控制器的性能有了明显改善,颤振最小,上升时间最短(交流直流为 0.0007 秒,直流直流为 1.5520 秒),平稳时间最快(交流直流为 0.0447 秒,直流直流为 2.0550 秒),稳态误差最小(交流直流为 0.0010%,直流直流为 0.0004%)。还进行了控制器硬件在环 (C-HIL) 实验,以确认控制器的实时适用性。
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引用次数: 0
An improved multi-channel and multi-scale domain adversarial neural network for fault diagnosis of the rolling bearing 用于滚动轴承故障诊断的改进型多通道多尺度域对抗神经网络
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-21 DOI: 10.1016/j.conengprac.2024.106120
Yongze Jin , Xiaohao Song , Yanxi Yang , Xinhong Hei , Nan Feng , Xubo Yang
To improve the fault diagnosis accuracy of rolling bearings under diverse working conditions, an improved domain adversarial neural network is proposed, the feature extraction module is reconstructed by multi-channel and multi-scale CNN-LSTM-ECA (MMCLE) in the proposed network. The MMCLE module consists of several key components. Firstly, the multi-channel multi-scale Convolutional Neural Networks (CNN) and Long Short-Term Memory (LSTM) are established to extract spatial features and temporal dependencies of the input data. Then, the Efficient Channel Attention (ECA) module is introduced to weight the effective feature channels. Finally, the domain adversarial training is employed to extract common features from both the source and target domains. By minimizing the domain offset between these domains, the faults of rolling bearing under diverse working conditions can be accurately diagnosed. The simulation results show that, based on the proposed MMCLE model, the domain offset issue can be effectively addressed, and the fault diagnosis accuracy can be improved for samples in the target domain under diverse working conditions. The accuracy and feasibility of the proposed method can be effectively verified.
为提高不同工况下滚动轴承的故障诊断精度,提出了一种改进的域对抗神经网络,其特征提取模块是通过多通道、多尺度 CNN-LSTM-ECA (MMCLE) 重构的。MMCLE 模块由几个关键部分组成。首先,建立多通道多尺度卷积神经网络(CNN)和长短期记忆(LSTM),以提取输入数据的空间特征和时间相关性。然后,引入高效通道注意(ECA)模块,对有效特征通道进行加权。最后,采用域对抗训练来提取源域和目标域的共同特征。通过最小化源域和目标域之间的域偏移,可以准确诊断不同工况下滚动轴承的故障。仿真结果表明,基于所提出的 MMCLE 模型,可以有效地解决域偏移问题,并提高不同工况下目标域样本的故障诊断精度。该方法的准确性和可行性得到了有效验证。
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引用次数: 0
A high-performance model predictive torque control concept for induction machines for electric vehicle applications 用于电动汽车感应机的高性能模型预测扭矩控制概念
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-19 DOI: 10.1016/j.conengprac.2024.106128
Georg Janisch , Andreas Kugi , Wolfgang Kemmetmüller
Induction machines are widely used in electric vehicles due to their high reliability and low costs. Controlling these machines to meet the high-performance demands presents a significant challenge since they are often operated at high speed and within operating ranges where magnetic saturation plays a significant role. Furthermore, specific motor parameters are not accurately known or vary during operation, e.g., due to temperature changes. Therefore, there is still a demand for control strategies to meet these demands systematically. This paper proposes a novel control strategy combining a model predictive control (MPC) concept with a fast feedback controller and a nonlinear observer. The proposed MPC strategy is based on a magnetic nonlinear model and allows for a long prediction horizon. It features high torque dynamics while ensuring energy optimality in the steady state. The results also show excellent performance for high rotational speeds and the operation at the system limits, outperforming state-of-the-art control concepts.
感应电机因其高可靠性和低成本而被广泛应用于电动汽车中。控制这些机器以满足高性能要求是一项重大挑战,因为它们通常是在高速运转和磁饱和起重要作用的工作范围内运行。此外,具体的电机参数并不准确,或者在运行过程中会发生变化,例如由于温度变化。因此,仍然需要控制策略来系统地满足这些需求。本文提出了一种结合模型预测控制(MPC)概念、快速反馈控制器和非线性观测器的新型控制策略。所提出的 MPC 策略基于磁性非线性模型,允许较长的预测范围。它具有高扭矩动态特性,同时确保稳态下的能量优化。研究结果还显示,该策略在高转速和系统极限运行时表现出色,优于最先进的控制概念。
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引用次数: 0
A reusable decoder network penalized by smooth group lasso and its applications to large-scale fault diagnosis of machinery 用平滑组套索惩罚的可重复使用解码器网络及其在大规模机械故障诊断中的应用
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-17 DOI: 10.1016/j.conengprac.2024.106127
Zhiqiang Zhang, Hongji He, Shuiqing Xu, Lisheng Yin, Xueping Dong
Representation learning approaches have achieved great success in fault diagnosis of large-scale mechanical data, among which the popular auto-encoder method has developed a series of effective variants. In the existing variants, the encoder network is re-employed to encode feature representations of the data, while the decoder network is directly discarded after training, leading to a regrettable waste of computational resources. Instead of proposing advanced variants of the auto-encoder, this paper explicitly penalizes the decoder network with group lasso, thereby transforming waste into treasure. Specifically, the group lasso constrains the column vectors of the decoder network’s weight matrix at the group level, making them reusable for feature selection. Moreover, a smooth function is utilized to approximate the group lasso to prevent numerical oscillations when computing the gradients. The simulated data and experimental gear data are sequentially used to verify the effectiveness of the smooth group lasso through investigations on two representative auto-encoder variants. The results show that the decoder network penalized by smooth group lasso can be re-utilized to guide selection of a subset of key features for training a classifier, exhibiting an extraordinary feature selection capability.
表征学习方法在大规模机械数据的故障诊断中取得了巨大成功,其中流行的自动编码器方法已发展出一系列有效的变体。在现有的变体中,编码器网络被重新用于对数据的特征表示进行编码,而解码器网络则在训练后被直接丢弃,这导致了令人遗憾的计算资源浪费。本文并没有提出自动编码器的高级变体,而是通过组套索(group lasso)对解码器网络进行明确的惩罚,从而变废为宝。具体来说,组套索在组的层面上对解码器网络权重矩阵的列向量进行约束,使其可重新用于特征选择。此外,在计算梯度时,利用平滑函数来近似组套索,以防止数值振荡。通过对两个具有代表性的自动编码器变体的研究,模拟数据和实验齿轮数据依次用于验证平滑组套索的有效性。结果表明,通过平滑组套索惩罚的解码器网络可以重新用于指导选择用于训练分类器的关键特征子集,表现出非凡的特征选择能力。
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引用次数: 0
Event-triggered formation control with obstacle avoidance for multi-agent systems applied to multi-UAV formation flying 应用于多无人机编队飞行的具有避障功能的多代理系统事件触发编队控制
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-16 DOI: 10.1016/j.conengprac.2024.106105
Liang Han , Yue Wang , Ziwei Yan , Xiaoduo Li , Zhang Ren
This study investigates time-varying formation control with communication constraint for general discrete-time multi-agent systems (MASs), which aims to control a swarm of agents to maintain a desired formation while avoiding obstacles in the scenario with spatial constraint. The event-triggered mechanism is introduced to effectively reduce the system communication frequency and an artificial potential field function is incorporated into the proposed controller to achieve obstacle avoidance in formation. The obtained results are applied to solve obstacle avoidance problems for multiple unmanned aerial vehicles (UAVs) in formation flight. Physical simulations are completed with four UAV models on a 3-D visualization simulation platform integrated by Robot Operating System (ROS) and Gazebo. Then, practical experiments are carried out with four quadrotors in a complex experimental scenario combined with the motion capture system. The physical simulation and practical experiments are implemented to verify the effectiveness of the theoretical results.
本研究探讨了一般离散时间多代理系统(MASs)具有通信约束的时变编队控制,旨在控制代理群在具有空间约束的场景中保持理想编队,同时避开障碍物。引入事件触发机制以有效降低系统通信频率,并将人工势场函数纳入所提出的控制器以实现编队避障。所获得的结果被应用于解决编队飞行中多个无人飞行器(UAV)的避障问题。在由机器人操作系统(ROS)和 Gazebo 集成的三维可视化仿真平台上完成了四种无人飞行器模型的物理仿真。然后,结合动作捕捉系统,在复杂的实验场景中使用四架四旋翼飞行器进行了实际实验。物理仿真和实际实验的实施验证了理论结果的有效性。
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引用次数: 0
Real-time model predictive control of path-following for autonomous vehicles towards model mismatch and uncertainty 面向模型不匹配和不确定性的自动驾驶汽车路径跟踪实时模型预测控制
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-16 DOI: 10.1016/j.conengprac.2024.106126
Wenqiang Zhao , Hongqian Wei , Qiang Ai , Nan Zheng , Chen Lin , Youtong Zhang
The path following function is a critical component of functional safety for autonomous vehicles, and following precision has garnered increased attention in practical applications. However, control performance can be compromised due to uncertainties in vehicle parameters and discrepancies between the control model and the actual vehicle to be controlled. To address this, a real-time model predictive control for path following of autonomous vehicles is proposed, incorporating an estimation of model mismatch. An adaptive extended Kalman filter is developed to estimate the potential model mismatch terms, and state deviations are compensated accordingly. Subsequently, a parameter-varying model predictive controller is formulated to achieve unbiased path-following control while maintaining robustness to parameter variations. Simulation results demonstrate a significant improvement in lateral following accuracy, with enhancements of 53.85%, 47.83%, and 42.86% compared to the nonlinear model predictive control, robust model predictive control, and learning-based control, respectively. The hardware-in-the-loop and real-road experiments further validate the excellent real-time executability, with a maximum time cost of 12.4 ms, accounting for 62% of the sampling period.
路径跟踪功能是自动驾驶车辆功能安全的重要组成部分,在实际应用中,跟踪精度越来越受到关注。然而,由于车辆参数的不确定性以及控制模型与实际受控车辆之间的差异,控制性能可能会受到影响。为解决这一问题,我们提出了一种用于自动驾驶车辆路径跟随的实时模型预测控制,其中包含对模型不匹配的估计。开发了一种自适应扩展卡尔曼滤波器来估计潜在的模型失配项,并对状态偏差进行相应补偿。随后,制定了参数变化模型预测控制器,以实现无偏的路径跟踪控制,同时保持对参数变化的鲁棒性。仿真结果表明,与非线性模型预测控制、鲁棒性模型预测控制和基于学习的控制相比,横向跟随精度有了显著提高,分别提高了 53.85%、47.83% 和 42.86%。硬件在环和实际道路实验进一步验证了其出色的实时可执行性,最大时间成本为 12.4 毫秒,占采样周期的 62%。
{"title":"Real-time model predictive control of path-following for autonomous vehicles towards model mismatch and uncertainty","authors":"Wenqiang Zhao ,&nbsp;Hongqian Wei ,&nbsp;Qiang Ai ,&nbsp;Nan Zheng ,&nbsp;Chen Lin ,&nbsp;Youtong Zhang","doi":"10.1016/j.conengprac.2024.106126","DOIUrl":"10.1016/j.conengprac.2024.106126","url":null,"abstract":"<div><div>The path following function is a critical component of functional safety for autonomous vehicles, and following precision has garnered increased attention in practical applications. However, control performance can be compromised due to uncertainties in vehicle parameters and discrepancies between the control model and the actual vehicle to be controlled. To address this, a real-time model predictive control for path following of autonomous vehicles is proposed, incorporating an estimation of model mismatch. An adaptive extended Kalman filter is developed to estimate the potential model mismatch terms, and state deviations are compensated accordingly. Subsequently, a parameter-varying model predictive controller is formulated to achieve unbiased path-following control while maintaining robustness to parameter variations. Simulation results demonstrate a significant improvement in lateral following accuracy, with enhancements of 53.85%, 47.83%, and 42.86% compared to the nonlinear model predictive control, robust model predictive control, and learning-based control, respectively. The hardware-in-the-loop and real-road experiments further validate the excellent real-time executability, with a maximum time cost of 12.4 ms, accounting for 62% of the sampling period.</div></div>","PeriodicalId":50615,"journal":{"name":"Control Engineering Practice","volume":"153 ","pages":""},"PeriodicalIF":5.4,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Multi-model integration for predicting circulating load ratio based on clustering SAG milling operating conditions 基于聚类 SAG 磨削操作条件的循环负载率预测多模型集成
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-15 DOI: 10.1016/j.conengprac.2024.106129
Zhenhong Liao , Ce Xu , Wen Chen , Feng Wang , Jinhua She
Grinding in mineral processing is used to control the ore at the technically feasible and economically optimum particle size to achieve mineral liberation for separation. A circulating-load ratio (CLR) during a semi-autogenous grinding (SAG) milling process is critical for controlling particle size and energy consumption. This paper presents a CLR-prediction model based on clustering SAG milling operating conditions. First, operating parameters affecting the CLR are identified by comprehensively analyzing the complex mechanism and characteristics of a typical industrial SAG milling process. Next, a method is developed to cluster operating conditions of the SAG milling process based on the power consumption and CLR of the process. The method reveals the actual physical significance of each operating condition. Then, support vector regression (SVR) is used to model the CLR in each operating condition. After that, a distance-based model integration strategy is designed to determine the weights of each SVR model to predict the CLR. Finally, integrating the SVR submodels yields a CLR prediction model. Actual run data demonstrated the accuracy and effectiveness of the model in predicting CLR. This method has significant practical value for improving SAG milling efficiency via its utilization in control system design.
矿物加工中的磨矿是将矿石控制在技术上可行、经济上最佳的粒度,以实现矿物分离。半自磨机(SAG)研磨过程中的循环负荷率(CLR)对于控制粒度和能耗至关重要。本文提出了一种基于 SAG 研磨操作条件聚类的 CLR 预测模型。首先,通过全面分析典型工业 SAG 研磨过程的复杂机理和特征,确定了影响 CLR 的操作参数。然后,根据 SAG 磨工艺的功耗和 CLR,开发了一种对 SAG 磨工艺操作条件进行聚类的方法。该方法揭示了每个运行条件的实际物理意义。然后,使用支持向量回归(SVR)对每种操作条件下的 CLR 进行建模。然后,设计一种基于距离的模型集成策略,以确定每个 SVR 模型的权重,从而预测 CLR。最后,对 SVR 子模型进行整合,得出 CLR 预测模型。实际运行数据证明了该模型预测 CLR 的准确性和有效性。这种方法在控制系统设计中的应用对于提高 SAG 磨矿效率具有重要的实用价值。
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引用次数: 0
Effectiveness of cooperative yaw control based on reinforcement learning for in-line multiple wind turbines 基于强化学习的在线多风力涡轮机协同偏航控制的有效性
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-15 DOI: 10.1016/j.conengprac.2024.106124
Longyan Wang , Qiang Dong , Yanxia Fu , Bowen Zhang , Meng Chen , Junhang Xie , Jian Xu , Zhaohui Luo
Wind farm wake interactions are critical determinants of overall power generation efficiency. To address these challenges, coordinated yaw control of turbines has emerged as a highly effective strategy. While conventional approaches have been widely adopted, the application of contemporary machine learning techniques, specifically reinforcement learning (RL), holds great promise for optimizing wind farm control performance. Considering the scarcity of comparative analyses for yaw control approaches, this study implements and evaluates classical greedy, optimization-based, and RL policies for in-line multiple wind turbine under various wind scenario by an experimentally validated analytical wake model. The results unambiguously establish the superiority of RL over greedy control, particularly below rated wind speeds, as RL optimizes yaw trajectories to maximize total power capture. Furthermore, the RL-controlled policy operates without being hampered by iterative modeling errors, leading to a higher cumulative power generation compared to the optimized control scheme during the control process. At lower wind speeds (5 m/s), it achieves a remarkable 32.63 % improvement over the optimized strategy. As the wind speed increases, the advantages of RL control gradually diminish. In consequence, the model-free adaptation offered by RL control substantially bolsters robustness across a spectrum of changing wind scenarios, facilitating seamless transitions between wake steering and alignment in response to evolving wake physics. This analysis underscores the significant advantages of data-driven RL for wind farm yaw control when compared to traditional methods. Its adaptive nature empowers the optimization of total power production across a range of diverse operating regimes, all without the need for an explicit model representation.
风场尾流相互作用是决定整体发电效率的关键因素。为了应对这些挑战,涡轮机的协调偏航控制已成为一种非常有效的策略。虽然传统方法已被广泛采用,但当代机器学习技术(特别是强化学习 (RL))的应用为优化风电场控制性能带来了巨大希望。考虑到偏航控制方法的对比分析很少,本研究通过实验验证的分析唤醒模型,对各种风况下的多风力涡轮机的在线偏航控制策略进行了经典的贪婪策略、优化策略和强化学习策略的实施和评估。结果清楚地表明,RL 比贪婪控制更有优势,尤其是在额定风速以下,因为 RL 优化了偏航轨迹,使总功率捕获最大化。此外,RL 控制策略的运行不受迭代建模误差的影响,在控制过程中与优化控制方案相比,累积发电量更高。在风速较低(5 米/秒)时,它比优化策略显著提高了 32.63%。随着风速的增加,RL 控制的优势逐渐减弱。因此,RL 控制提供的无模型适应性大大增强了在各种风速变化情况下的稳健性,促进了尾流转向和对准之间的无缝转换,以应对不断变化的尾流物理特性。与传统方法相比,这项分析强调了数据驱动 RL 在风电场偏航控制方面的显著优势。其自适应性使其能够在各种不同的运行状态下优化总发电量,而无需明确的模型表示。
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引用次数: 0
Multivariable switching control of a compliant piezoelectric microgripper with force/position interaction interferences 具有力/位置相互作用干扰的顺应式压电微型夹持器的多变量开关控制
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-12 DOI: 10.1016/j.conengprac.2024.106102
Gaohua Wu , Yiling Yang , Yuguo Cui , Guoping Li , Yanding Wei
This paper presents multivariable switching control of a piezoelectric microgripper regarding its output displacement, gripping force, and manipulated position. Unlike existing microgripper control, it simultaneously regulates force/position variables. Meanwhile, force/position interaction interferences and signal itself overshooting are suppressed. Firstly, a symmetrical microgripper with two independent gripping arms is introduced. Then, a generalized dynamic model is established by considering structural dynamics, electromechanical coupling, and force/position interaction. After that, multivariable switching control is proposed to achieve clamp-carry-release manipulation using dual-input and dual-output (DIDO) perturbation displacement and force/position controllers. Finally, various switching experiments are conducted, demonstrating that force/position interaction interferences are reduced by 83.76 % and 87.51 %, and interference-suppression time is shortened from 0.86 s and 0.70 s to 0.49 s and 0.41 s. Also, overshoots of gripping force and position are eliminated with a smaller settling time. The proposed multivariable switching control exhibits superior regulation performance, guaranteeing manipulation accuracy and stability.
本文介绍了压电微型机械手输出位移、抓取力和操纵位置的多变量开关控制。与现有的微机械手控制不同,它同时调节力/位置变量。同时,力/位置相互作用干扰和信号本身的过冲也被抑制。首先,介绍了具有两个独立抓取臂的对称微型机械手。然后,通过考虑结构动力学、机电耦合和力/位置相互作用,建立了广义动态模型。然后,提出了多变量切换控制,利用双输入双输出(DIDO)扰动位移和力/位置控制器实现夹持-释放操纵。最后,进行了各种切换实验,结果表明力/位置交互干扰分别减少了 83.76 % 和 87.51 %,干扰抑制时间从 0.86 秒和 0.70 秒缩短到 0.49 秒和 0.41 秒。所提出的多变量开关控制具有优异的调节性能,保证了操纵精度和稳定性。
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引用次数: 0
A framework for joint vehicle localization and road mapping using onboard sensors 利用车载传感器进行联合车辆定位和道路测绘的框架
IF 5.4 2区 计算机科学 Q1 AUTOMATION & CONTROL SYSTEMS Pub Date : 2024-10-10 DOI: 10.1016/j.conengprac.2024.106112
Karl Berntorp, Marcus Greiff
This paper presents a modeling framework for joint estimation of a host vehicle state and a map of the road based on global navigation satellite system (GNSS) and camera measurements. We model the road using a spline representation based on lower-dimensional Bézier curves parametrized in generalized endpoints (GEPs) with implicit guarantees of continuous lane boundaries. We model the GEPs by a parameter vector having a Gaussian prior representing the uncertainty of the prior map, and provide a systematic way of defining this prior from generic map representations. Both GNSS and camera measurements, such as lane-mark measurements, have noise characteristics that vary in time. To adapt to the changing noise levels and hence improve positioning performance, we formulate the problem as a joint vehicle state, map parameter, and noise covariance estimation problem and present two noise-adaptive linear-regression Kalman filters (LRKFs); (i) an interacting multiple-model (IMM) LRKF and (ii) a variational-Bayes (VB) LRKF. We conduct a Monte-Carlo study and compare the two approaches in terms of estimation precision and computation times. Embedded implementations in an automotive-grade dSpace Micro Autobox-II indicate the real-time validity of both approaches, with turn-around times of between 2–80ms, depending on the problem size and if the map is updated. The results indicate that while the IMM-LRKF shows marginally better estimation accuracy, the VB-LRKF is at least a factor of 2 faster.
本文提出了一个建模框架,用于根据全球导航卫星系统(GNSS)和摄像头的测量结果,联合估算主机车辆状态和道路地图。我们使用基于低维贝塞尔曲线的样条表示法对道路进行建模,该样条表示法以广义端点(GEP)为参数,并隐含连续车道边界的保证。我们通过参数向量对 GEPs 进行建模,该参数向量具有代表先验地图不确定性的高斯先验,并提供了从通用地图表示法定义该先验的系统方法。全球导航卫星系统和相机测量(如车道标记测量)都具有随时间变化的噪声特性。为了适应不断变化的噪声水平,从而提高定位性能,我们将问题表述为一个联合车辆状态、地图参数和噪声协方差估计问题,并提出了两个噪声自适应线性回归卡尔曼滤波器(LRKF):(i) 交互多模型(IMM)LRKF 和 (ii) 可变贝叶斯(VB)LRKF。我们进行了蒙特卡洛研究,并在估计精度和计算时间方面对这两种方法进行了比较。在汽车级 dSpace Micro Autobox-II 中的嵌入式实现表明,这两种方法都具有实时有效性,根据问题大小和地图是否更新,周转时间在 2-80 毫秒之间。结果表明,虽然 IMM-LRKF 的估计精度略高,但 VB-LRKF 至少快 2 倍。
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引用次数: 0
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Control Engineering Practice
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