Browse Topic: Congestion
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In response to the problems of urban traffic congestion and the limited expansion of infrastructure, this paper conducts two core research focusing on the intelligent chassis system of split-type flying vehicle. Firstly, an autonomous navigation strategy for the intelligent chassis module is proposed based on chassis module Navigation 2 architecture, which fuses LIDAR and IMU positioning to plan paths using the A* global planning algorithm on a global cost map, and update the local cost map in real time with sensor data. It is orchestrated by the BT Navigator using a behavior tree, with failures handled by the Recovery Server, to achieve autonomous driving across multiple waypoints. In simulation and closed-field experiments, the system can stably reach the preset target points. The positioning accuracy and trajectory tracking performance can meet the design requirements. Secondly, a mechanical slide rail-type docking structure adapted to the split flying vehicle architecture is designed. Deformation analysis under the representative working conditions are evaluated through finite element software. The test results show that the maximum deformation of this docking structure under typical load is significantly lower than the docking tolerance and positioning repeatability requirements. The structural stiffness and stability meet the design indicators. The above work indicates that the proposed autonomous navigation strategy and the docking structure for the intelligent chassis can effectively support the modular operation of “air trunk & ground terminal” mode, providing a scientific basis for the functional integration and system reliability research of split-type flying vehicles.
Growing population in Indian cities has led to packed roads. People need a quick option to commute for both personal trips and business needs. The 2-3 Wheel Combination Vehicle is a new, modular solution that switches between a two-wheeler (2W) and a three-wheeler (3W). Hero has designed SURGE S32 to be a sustainable and flexible transportation option. It is world’s first class changing vehicle. The idea is to use a single vehicle for zipping through city traffic, making deliveries, or earning an income. Manufactured to deal with the challenges of modern life, this dual-battery convertible vehicle can easily transform from a two-wheeler to a three-wheeler and vice versa within three minutes. The Surge S32 is a versatile vehicle that replaces the need for multiple specialised vehicles. By lowering the number of vehicles on the road, it decreases road congestion, reduces emissions, and improves livelihoods. It powers by electricity, ensuring sustainability in all aspects. The current Central Motor Vehicle Rules (CMVR) lacked a clause for something this new. A vehicle was either a two-wheeler or a three-wheeler, not both. You might wonder, "How do you even make rules for a vehicle that embodies dual characteristics?” For a new idea to hit the streets, you need new rules. The Ministry of Road Transport & Highways (MoRTH) under the Central Motor Vehicle Rules (CMVR) created a new L2-5 category and established a unique regulatory framework. Developed with our best safety experts and industry minds, this new framework is the foundation that allows these vehicles to exist legally and safely. It shows that India is not just building the vehicles of the future, but the rules for them too. CMVR approval framework for the L2-5 category has made it mandatory for these vehicles to comply with newly formulated standard AIS-177, which was developed carefully with pilot testing and stakeholders inputs. This category balances innovation with practical implementation. It also harmonizes taxation and insurance, while integrating seamlessly with the National Vehicle Registration Portal of India (VAHAN) system at the Regional Transport Office (RTO) level for streamlined registration and dual-configuration. The 2-3W Combi Vehicle establishes a new standard for sustainable urban mobility in India by integrating versatility, safety, and regulatory foresight.
With the acceleration of urbanization, freeway traffic congestion is becoming increasingly serious, especially at entrance ramps, where the concentrated inflow of traffic often leads to increased traffic pressure on the mainline, affecting the overall access efficiency. In order to alleviate the ramp congestion problem, this paper proposes a deep reinforcement learning-based intelligent control method for entrance ramps of network-connected vehicles, which adopts Proximal Policy Optimization (PPO) algorithm to optimize the ramp vehicle flow and speed control strategy in real time by constructing a reinforcement learning control framework. In this paper, simulation experiments are conducted in different traffic density scenarios and compared with the traditional reinforcement learning algorithms DQN and A2C. The experimental results show that the PPO algorithm is able to converge quickly in low, medium and high traffic densities, significantly improve the cumulative reward value, and exhibit higher stability and superiority compared with other algorithms. The research in this paper not only provides an intelligent solution for ramp flow optimization, but also provides theoretical support and technical reference for the development of intelligent transportation system.
The road network is a critical component of modern urban mobility systems, with signalized traffic intersections playing a pivotal role. Traditionally, traffic light phase timings and durations at intersections are designed by transportation engineers using historical traffic data. Some modern intersections employ trigger-based mechanisms to improve traffic flow; however, these systems often lack global awareness of traffic conditions across multiple intersections within a network. With the increasing availability of traffic data and advancements in machine learning, traffic light systems can be enhanced by modeling them as agents operating in an environment. This paper proposes a Reinforcement Learning (RL) based approach for multi-agent traffic light systems within a simulation environment. The simulation is calibrated using real-world traffic data, enabling RL agents to learn effective control strategies based on realistic scenarios. A key advantage of using a calibrated simulation is that RL agents can experiment with different control actions without compromising safety in real-world traffic. The proposed system demonstrates that RL agents can coordinate and learn optimal policies, effectively reducing overall vehicle wait times in heavy urban traffic scenarios. The reward function is carefully designed to minimize traffic congestion by reducing vehicle wait times. A comparative study between static phase timings, currently used by conventional controllers, and the RL-based policy highlights significant reductions in overall wait times. Additionally, this simulation-based approach allows RL agents to be deployed in real-time, continuously learning and adapting to live traffic data. By implementing updated control policies for traffic light phase timings, the system can effectively reduce congestion and improve traffic flow across the network.
The conventional process of last-mile delivery logistics often leads to safety problems for road users and a high level of environmental pollution. Delivery drivers must deal with frequent stops, search for a convenient parking spot and sometimes navigate through the narrow streets causing traffic congestion and possibly safety issues for the ego vehicle as well as for other traffic participants. This process is not only time consuming but also environmentally impactful, especially in low-emission zones where prolonged vehicle idling can lead to air pollution and to high operational costs. To overcome these challenges, a reliable system is required that not only ensures the flexible, safe and smooth delivery of goods but also cuts the costs and meets the delivery target. In the dynamic landscape of last-mile delivery, LogiSmile, an EU project, introduced a solution to urban delivery challenges through an innovative cooperation between an Autonomous Hub Vehicle (AHV) and an Autonomous Delivery Device (ADD). This work addresses not only these challenges but also provides insight into a future where last-mile delivery is safer, more efficient and nature friendly. As a part of this project, an integrated safety system architecture has been developed for the AHV, featuring a dependability cage (DC) for onboard monitoring of a single autonomous vehicle and a remote command control center (CCC) for offboard monitoring of a fleet of autonomous vehicles. Operating at SAE levels 3/4 (SAE L3/4), the AHV incorporates a safety driver and a monitoring system, ensuring compliance with SAE guidelines. The DC enables safe transitions to degraded/ fail-safe driving modes in response to safety violations of the autonomous driving system (ADS), optimizing the vehicle's operational safety. Additionally, the CCC enhances autonomy by redundantly monitoring the fleet of vehicles via real-time sensor streams, also facilitating the communication with the ADD and the reconfiguration of the driving mode depending on the current road scenario. The project results were successfully demonstrated in Hamburg in 2022, showcasing the practical implementation of the developed safety architecture and the insights gained.
This research investigates platoon dispersion characteristics in mixed-traffic flow of autonomous and human-driven vehicles. It presents a cellular automata-based platoon dispersion model. The study’s key findings are as follows: platoon dispersion initially increases and then decreases with the rise in autonomous vehicle proportions. When the autonomous vehicle proportion is approaching 100%, platoon dispersion descends rapidly and is completely eliminated while the proportion is 100%. Compared to platoon consisting entirely of human-driven vehicles, the peak value of standard deviation of vehicle speed is 1.71 times and the travel time drops by 38.19% when the proportion is 1. Moreover, the lane-changing behavior enhances platoon speed, acceleration, and space utilization at micro- and macrolevels by optimizing space resource allocation within the platoon. The study employs a two-lane mixed-flow platoon dispersion model that assumes uniform vehicle characteristics and prioritizes maximizing travel efficiency for autonomous vehicles. These findings bear significant implications for transportation planning and management, providing valuable insights for policymakers, transportation engineers, and researchers.
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