Research on the water and land motion performance of an amphibious vehicle

Abstract

The key motions of land and water are analyzed for a designed amphibious carrier robot. On land, based on the characteristics of the multi-joint crawler, the robot has planned two gaits for climbing steps on land. The kinematic models of climbing steps and climbing steps are established for the two planned gaits, and the maximum height that the robot can climb steps is obtained based, Based on the laws of dynamics, the stability equation of the robot under strong transient impact is established to obtain the conditions for the robot to maintain its own stability when the robot is under strong transient impact during traveling, which provides a theoretical basis for the attitude control of the robot arm. In the water, the fluid numerical method is used to simulate the underwater motion of the robot's swing arm in the extended and retracted state, obtain the traveling resistance and surface pressure of the robot's swing arm crawler in the two states, analyze the relationship between the robot's traveling resistance and speed, obtain the relationship expression between the robot's traveling resistance and the traveling speed, and provide data support of the state selection and speed setting of the robot's underwater crawler.

Effect of meso‐structure characteristics on surface emissivity of 2.5D Woven ablative composite for thermal protection

“…Fiber tows are opaque surface and the emissivity changes with temperatures from 1273 to 1873 K, which is obtained from experimental data and shown in Table 1. [ 53 ] where the subscripts in and out represent radiation from air striking to tows and radiation from tows to air. It shows that the input radiation from semitransparent air strikes to surfaces of fiber tows (the first term of the right side) and then is reflected (the second term of the right side).…”

Design and Ground Performance Evaluation of a Multi-Joint Wheel-Track Composite Mobile Robot for Enhanced Terrain Adaptability

“…There are currently many wheeled and tracked hybrid mobile robots available, such as the VIPER robot developed by Israeli Elbit Systems, the Lizard intelligent robot, developed by the Shenyang Institute of Automation, and research robots cited in the literature [9][10][11][12][13]. These robots take advantage of the benefits of combining wheels and tracks, providing good obstacle traversal capabilities and adaptability to various complex terrains.…”

“…The wheel-tracked composite robot is shown in Figure 1. Compared to the design in the literature [10], our robotic platform has undergone significant improvements. One of the major changes we made was to adopt a pendulum wheel design with different sizes between the front and rear.…”

“…Yonggan Wang et al, analyzed the crucial movements for their self-designed amphibious delivery robot on water and land. However, the robot's large body mass (resulting from the swing arm wheel being the same size as the main wheel) and the overly complicated and inefficient gait when climbing stairs are due to structural limitations [10]. Zhang, S., et al, proposed an adaptive wheel-legged shape reconfigurable mobile robot and conducted a kinematics analysis of the robot's ability to climb obstacles, stairs, and gullies.…”

“…In this paper, the focus is on analyzing the ground performance of an urban mobile robot operating in a complex environment. To enhance movement efficiency, obstacle traversal capabilities, and overall stability in complex environments, a multi-joint wheelrail composite mobile robot was designed by drawing from the literature [10]. The rest of the paper is structured as follows.…”