Lateral motion pin device for tactile communication: an approach with DC mini-motors

AbstractThis paper proposes a lateral lane change obstacle avoidance constraint control simulation algorithm based on the driving behavior recognition of the preceding vehicles in adjacent lanes. Firstly, the driving behavior of the preceding vehicles is recognized based on the Hidden Markov Model, this research uses longitudinal velocity, lateral displacement and lateral velocity as the optimal observation signals to recognize the driving behaviors including lane-keeping, left-lane-changing or right-lane-changing; Secondly, through the simulation of the dangerous cutting-in behavior of the preceding vehicles in adjacent lanes, this paper calculates the ideal front wheel steering angle according to the designed lateral acceleration in the process of obstacle avoidance, designs the vehicle lateral motion controller by combining the backstepping and Dynamic Surface Control, and the safety boundary of the lateral motion is constrained based on the Barrier Lyapunov Function; Finally, simulation model is built, and the simulation results show that the designed controller has good performance. This active safety technology effectively reduces the impact on the autonomous vehicle safety when the preceding vehicle suddenly cuts into the lane.

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Design, static analysis and development of a new three-legged shake table

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211018487 ◽

2021 ◽

pp. 095440622110184

Author(s):

Ganesh Mangavu ◽

Anjan Kumar Dash

Keyword(s):

Vertical Motion ◽

Torsional Stiffness ◽

Shake Table ◽

Lateral Motion ◽

Sinusoidal Motion ◽

Gravity Load ◽

Simulation Results ◽

Electromechanical Actuation ◽

Translational Stiffness ◽

Earthquake Data

In this paper, an alternative design is proposed based on a family of three-legged manipulators. Such manipulators have two actuators (one vertical and one horizontal) in each leg, unlike the standard UP̅S Stewart platform, which has one actuator in each leg. The arrangement of the two actuators is such a way that, to have vertical motion of the shake table only the Vertical Motion Actuators (VMA) are actuated and for longitudinal or lateral motion, the Horizontal Motion Actuators (HMA) alone are moved. Due to its inherent features such as simplified kinematics, control and distributed loading, a study is carried out to determine the performance of such three-legged manipulators as a shake table. Sinusoidal motion and white noise motions are given to the actuators and shown that the VMA forces have linear relationship with the platform forces. The translational stiffness and the torsional stiffness are studied separately for the manipulators. In the dynamic analysis, it is highlighted that the gravity load of the legs is borne by the Vertical actuators, irrespective of the motion being spatial or planar. Hence, this topology provides scope for lighter electromechanical actuation. The performance analysis of the 3 legged configuration is accomplished using simulation results, in comparison to a 7-UP̅S configuration of shake table. A prototype of the shake table is fabricated and tested with earthquake data of El Centro.

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Structural organization and cohesiveness of foraging groups in Camponotus sericeus (Fabricius) (Hymenoptera: Formicidae): locally regulated or self-organized?

BMC Zoology ◽

10.1186/s40850-020-00062-6 ◽

2020 ◽

Vol 5 (1) ◽

Author(s):

Panayanthatta Ashwathi ◽

Barman Puspita ◽

K. N. Ganeshaiah

Keyword(s):

Small Groups ◽

Structural Organization ◽

Middle Part ◽

Entire Group ◽

Chaotic Search ◽

Self Organized ◽

Single File ◽

Tail Part ◽

Tactile Communication ◽

Group B

Abstract Background In Camponotus sericeus (Fabricius), foraging ants are recruited mostly as individuals but occasionally as small groups that move in a single file. We studied the structure and organization of these small foraging groups and attempted to understand the process through which the cohesiveness of the moving file is maintained. Results The recruited group moves in a single file as if steered by a leader at the moving tip. Ants in the group were found to exhibit certain fidelity to their respective positions in the file, despite the occasional breakdown of the cohesiveness due to disturbance and or obstructions on their path. This fidelity decreases from both ends towards the middle part of the file. Accordingly, three segments could be recognized in the moving file: (a) the leading ant that almost always maintains its position and steers the group, (b) a short tail part with a few ants that always trail the file and, (c) the mid part that binds the group; ants in this segment always tend to follow the leader through a cascading chain of tactile communication. If the leader ant is removed, entire group loses its orientation and enters into a chaotic search state. But removing any other ant does not affect the cohesiveness; rather it’s position is occupied by the member preceding it and thus maintains the link in the group. Conclusions The cohesiveness of the moving group appeared to result from (a) regulation of the movement of the group by the leading ant, and, (b) an interactive process among the rest of the ants. Based on these two elements, a simple automated model of the group’s movement was developed that could effectively mimic the observed pattern. We also provide evidence to suggest that recruitment of groups occurs in the direction of, and in response to, the information received by the colony on, the resource rich patches.

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Inactivation of Semicircular Canals Causes Adaptive Increases in Otolith-Driven Tilt Responses

Journal of Neurophysiology ◽

10.1152/jn.00775.2001 ◽

2002 ◽

Vol 87 (3) ◽

pp. 1635-1640 ◽

Cited By ~ 21

Author(s):

Dora E. Angelaki ◽

Shawn D. Newlands ◽

J. David Dickman

Keyword(s):

Eye Movements ◽

Semicircular Canal ◽

Translational Motion ◽

Semicircular Canals ◽

Vertical Axis ◽

Lateral Motion ◽

Functional Interaction ◽

Gaze Stabilization ◽

Theoretical Evidence ◽

Ocular System

Growing experimental and theoretical evidence suggests a functional synergy in the processing of otolith and semicircular canal signals for the generation of the vestibulo-ocular reflexes (VORs). In this study we have further tested this functional interaction by quantifying the adaptive changes in the otolith-ocular system during both rotational and translational movements after surgical inactivation of the semicircular canals. For 0.1–0.5 Hz (stimuli for which there is no recovery of responses from the plugged canals), pitch and roll VOR gains recovered during earth-horizontal (but not earth-vertical) axis rotations. Corresponding changes were also observed in eye movements elicited by translational motion (0.1–5 Hz). Specifically, torsional eye movements increased during lateral motion, whereas vertical eye movements increased during fore-aft motion. The findings indicate that otolith signals can be adapted according to a compromised strategy that leads to improved gaze stabilization during motion. Because canal-plugged animals permanently lose the ability to discriminate gravitoinertial accelerations, adapted animals can use the presence of gravity through otolith-driven tilt responses to assist gaze stabilization during earth-horizontal axis rotations.

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