Model Reference Adaptive Control and Fuzzy Neural Network Synchronous Motion Compensator for Gantry Robots

A model reference adaptive control and fuzzy neural network (FNN) synchronous motion compensator for a gantry robot is presented in this paper. This paper proposes the development and application of gantry robots with MRAC and FNN online compensators. First, we propose a model reference adaptive controller (MRAC) under the cascade control method to make the reference model close to the real model and reduce tracking errors for the single axis. Then, a fuzzy neural network compensator for the gantry robot is proposed to compensate for the synchronous errors between the dual servo motors to improve precise movement. In addition, an online parameter training method is proposed to adjust the parameters of the FNN. Finally, the experimental results show that the proposed method improves the synchronous errors of the gantry robot and demonstrates the methodology in this paper. This study also successfully integrates the hardware and successfully verifies the proposed methods.

Design and Implementation of Morphed Multi-Rotor Vehicles with Real-Time Obstacle Detection and Sensing System

Multirotor unmanned aerial vehicles (MUAVs) are becoming more prominent for diverse real-world applications due to their inherent hovering ability, swift manoeuvring and vertical take-off landing capabilities. Nonetheless, to be entirely applicable for various obstacle prone environments, the conventional MUAVs may not be able to change their configuration depending on the available space and perform designated missions. It necessitates the morphing phenomenon of MUAVS, wherein it can alter their geometric structure autonomously. This article presents the development of a morphed MUAV based on a simple rotary actuation mechanism capable of driving each arm’s smoothly and satisfying the necessary reduction in workspace volume to navigate in the obstacle prone regions. The mathematical modelling for the folding mechanism was formulated, and corresponding kinematic analysis was performed to understand the synchronous motion characteristics of the arms during the folding of arms. Experiments were conducted by precisely actuating the servo motors based on the proximity ultrasonic sensor data to avoid the obstacle for achieving effective morphing of MUAV. The flight tests were conducted to estimate the endurance and attain a change in morphology of MUAV from “X-Configuration” to “H-Configuration” with the four arms actuated synchronously without time delay.

Synchronous facial action binds dynamic facial features

We asked how dynamic facial features are perceptually grouped. To address this question, we varied the timing of mouth movements relative to eyebrow movements, while measuring the detectability of a small temporal misalignment between a pair of oscillating eyebrows—an eyebrow wave. We found eyebrow wave detection performance was worse for synchronous movements of the eyebrows and mouth. Subsequently, we found this effect was specific to stimuli presented to the right visual field, implicating the involvement of left lateralised visual speech areas. Adaptation has been used as a tool in low-level vision to establish the presence of separable visual channels. Adaptation to moving eyebrows and mouths with various relative timings reduced eyebrow wave detection but only when the adapting mouth and eyebrows moved asynchronously. Inverting the face led to a greater reduction in detection after adaptation particularly for asynchronous facial motion at test. We conclude that synchronous motion binds dynamic facial features whereas asynchronous motion releases them, allowing adaptation to impair eyebrow wave detection.

Research on distributed real-time synchronous motion control based on time-sensitive networking

As a set of protocol standards defining time sensitive mechanism of Ethernet data transmission, Time sensitive network (TSN) can support transmission of isochronous data and non-periodic data in the same network . Distributed synchronous control plays an important role in large precision manufacturing scene. In this paper, a distributed real-time synchronous motion control scheme of two motors based on TSN is proposed, and the experiment shows that the two motors moving at high speed can still maintain phase synchronization under the scheduling mechanism of IEEE Std 802.1Qbv even if there is a large traffic load in the network.

Melt into the group Electrophysiological Evidence of Gestalt Perception of Human Dyad

It has been showed recently that the human brain has dedicated networks for perception of human bodies in synchronous motion or in situation of interaction. However, below motion and interaction, how does the brain process a simple plurality of humans in close positioning? We used EEG frequency tagging technique to investigate integration of human dyad elements in a global percept. We presented to participants images of two silhouettes, a man and a woman flickering at different frequencies (5.88 vs. 7.14 Hz). Clear response at these stimulation frequencies reflected response to dyad parts, both when the dyad was presented upright and inverted. However, an emerging intermodulation component (7.14 + 5.88 = 13.02 Hz), a nonlinear response regarded as an objective signature of holistic representation, was significantly enhanced in upright relatively to inverted position. Inversion effect was significant only for the intermodulation component as opposed to stimulation frequencies revealing that dyad configuration perception overrides structural properties of dyad elements. Inversion effect was not significant for a pair of non-human objects. Our results show that merely facing two humans in close positioning leads to perceptually bind them and suggest that the perception of individuals is of different nature when they form a plurality.

Design of Insertion Mechanism with Friction Wheels for Cannula Flexible Needle Based on TRIZ

Background: Flexible needle insertion is one of the minimally invasive surgeries, which takes advantage of the lateral force acted on the bevel tip to make the needle shaft bend when inserted into the tissue. The bending makes the needle avoid the obstacles (like bones, veins, nerves, etc.) in order to reach the target. However, the traditional flexible needle neither can change its curvature of the path, nor can realize a precise control because of the torsional friction between the needle and the tissue. Hence, a cannula flexible needle was proposed to overcome the drawbacks, which consists of a cannula and a stylet. Also, there is a need of an insertion mechanism for the cannula flexible needle in robot-assisted surgery. Objective: The aim of this paper is to innovatively design an insertion mechanism with friction wheels for the cannula flexible needle, which is used as an end-effector in robot-assisted surgery system. The mechanism is supposed to realize the coordinated driving of the cannula and the stylet in order to achieve variable curvatures of paths. Methods: Making references of the patents and research papers on needle insertion mechanisms, and based on the requirement of degree of freedom for the cannula flexible needle insertion, the insertion mechanism for the cannula flexible needle is designed by using the TRIZ theory. The conflicts matrix analysis, the invention principles and the substance-field analysis are used to innovatively design the driving scheme and the synchronous motion mechanism. Results and Conclusion: In this paper, the concrete structure design of the insertion mechanism for the cannula flexible needle is achieved, which is compact and simple. The friction coefficient between the needle and the wheels, and the pretightening force between both wheels are calculated through the data from experiments. The insertion accuracy of friction wheel mechanism is tested and analyzed through experimentation. The results show that the maximum placement error of the needle executed by the insertion mechanism is less than 0.5 mm, which meets the demands of surgical operations.