Influence Of Travel Speed Research Articles

Have a Good Travel Time in Routing: Bibliometric Analysis, Literature Review, and Future Directions

ABSTRACTTravel time serves as a critical factor in routing problems, affecting routing decisions, congestion avoidance, and environmental sustainability. In this study, a thorough bibliometric and network analysis is presented based on 1752 documents collected from Web of Science published in the past three decades. CiteSpace is adopted to generate research clusters for topological analysis that graphically illustrate the publications' evolution over time and identify the current state and the emerging trends of routing problems with travel time focus. The collaboration network explores the cooperation patterns between countries and institutions. Attention toward the time‐dependency, uncertainty, dynamic characteristics of travel time, and the influence of travel speed on emissions, is uncovered through document co‐citation analysis. Furthermore, a comprehensive review of the literature has been conducted from an information quality and evolution perspective. Realistic scenarios such as fuel consumption and traffic conditions are eliciting more attention. Significant emphasis is increasingly placed on the time dependency, reliability, uncertainty, and dynamics of travel time. This study systematically reviews and analyzes relevant research on routing problems with travel time focus, identifying key emerging trends and knowledge gaps, and offering valuable insights for future research.

Influence of travel speed on porosity and liquation cracking in cold wire pulsed gas metal arc welding of aa7075-t651 aluminum alloy

Influence of travel speed on porosity and liquation cracking in cold wire pulsed gas metal arc welding of aa7075-t651 aluminum alloy

Influence of travel speed on microstructure and mechanical behavior of Inconel 625 fabricated using wire fed laser directed energy deposition

The printing of Inconel 625 via wire-fed laser directed energy deposition is required for the near net shape fabrication of large scale components. In this study, an array of processing parameters was tested to identify a defect-free low-travel-speed and high-travel speed parameter for wire-fed laser directed energy deposition of Inconel 625. Samples printed using these parameters were subject to characterization in terms of grain morphology and tensile properties. Results showed that the high-travel-speed parameter had a refined columnar+equiaxed grain structure, whereas the low-travel-speed parameter had a columnar grain structure. The experimentally observed microstructure is correlated to the processing parameters by calculation of the solidification rate and thermal gradient. When tested perpendicular to the build direction, both parameters exhibited a similar yield strength. When tested parallel to the build direction, the high-travel-speed parameter exhibited a higher yield strength than the low-travel-speed parameter. For both parameters, samples pulled parallel to the build-direction showed a lower yield strength than samples pulled perpendicular to the build direction. The differences in yield strength for differing parameters and orientation are attributed primarily to dislocation strengthening.

Analysis of Position and State Estimation of Quadruped Robot Dog Based on Invariant Extended Kalman Filter

Abstract: Compared with the state estimation of quadruped robots based on external sensors such as camera and lidar, the state estimation based on body sensors can provide high-frequency and stable odometer estimation. By analyzing the state estimation methods of the legged robot based on the body sensor, the invariant extended Kalman filter (IEKF) based on the body sensor is determined to conduct the state estimation analysis of the quadruped robot. Through various path tracking experiments in simulation and real environment, the influence of travel speed, travel distance and different steering angles on the position state estimation results was analyzed, and the IEKF model was optimized by compensating the angular velocity. Experiments show that within the set speed range, after adding angular velocity compensation, the position estimation accuracy error of the robot dog is well controlled and is less than 1%.

Influence of travel speed on the microstructural evaluation and mechanical characteristics of bobbin tool friction stir-welded thick AA5456-H112 plates

5456-H112 aluminum alloy plates with a thickness of 20 mm were joined using floating-bobbin tool friction stir welding at different travel speeds from 28 to 160 mm/min and a fixed rotational speed of 90 rpm. The results of microstructural analysis indicated that the grain size is decreased at a constant travel speed (at each of the speeds of 28, 40, 56, 80, 112, and 160 mm/min), from the retreating side to the advancing side of the joints whereas the density and the size of the intermetallic compounds are increased. Increasing the travel speed also reduces heat input and recrystallized grain size of the stirred region leading to increased hardness of the joints. The tensile test results showed that the ultimate tensile strength, yield strength, and elongation of the welded samples initially increase by increasing the travel speed and then start to decrease due to the formation of defects in the stir zone. The fracture of all transverse tensile test specimens occurs on the advancing side of the joints. The fracture location of the best specimen is located at the adjacent of the base metal with the heat-affected zone. The maximum mechanical properties are achieved at a travel speed of 40 mm/min, and the welding efficiency in that condition is approximately 97%.

Influence of travel speed on microstructure and mechanical properties of wire + arc additively manufactured 2219 aluminum alloy

Wire + arc additive manufacturing (WAAM) was preliminarily employed to fabricate the 2219 aluminum alloy. The influence of the electric arc travel speed (TS) on the macro-morphology, microstructure, and mechanical properties were investigated. The results indicated that as the electric arc TS increased, the size and the volume fraction of equiaxed grain decreased. The high arc TS during WAAM also promoted the precipitation of the θ (Al2Cu) phase. The volume fractions of θ″ and θ′ phases reached maximum values when TS is 350 and 250 mm/min, respectively. The thermal cycle facilitated the precipitation of the θ′ phase. In addition, the micro-hardness and tensile strength of the alloy were analyzed, and the results indicated that samples fabricated at TS of 350 mm/min possessed finer equiaxed grain and exhibited higher ultimate tensile strength (273.5 MPa) and yield strength (182.9 MPa) compared to those fabricated at 250 mm/min.

Demonstrating Tractor Performance Trends using Lotus Templates

Tractor performance results obtained from Lotus templates were demonstrated. Comparison of bias-ply versus radial-ply tires, dual versus single tires, and the influence of travel speed, tire size, ballast distribution, soil condition, two-wheel-drive (2WD) and four-wheeldrive/mechanical-front-wheel-drive (4WD/MFWD) tractors was shown. An alternative calculation mode can be used to determine the required weight to obtain a desired performance. This mode was used with an optimizing ballast scheme to predict the optimum wheel slip and maximum tractor efficiency for each comparison. The tractor performance templates have been used as an educational tool to demonstrate these comparative features to both undergraduate classes and farm clientele.