Genetic Algorithm-Based Trajectory Optimization for Digital Twin Robots

Mobile robots have an important role in material handling in manufacturing and can be used for a variety of automated tasks. The accuracy of the robot’s moving trajectory has become a key issue affecting its work efficiency. This paper presents a method for optimizing the trajectory of the mobile robot based on the digital twin of the robot. The digital twin of the mobile robot is created by Unity, and the trajectory of the mobile robot is trained in the virtual environment and applied to the physical space. The simulation training in the virtual environment provides schemes for the actual movement of the robot. Based on the actual movement data returned by the physical robot, the preset trajectory of the virtual robot is dynamically adjusted, which in turn enables the correction of the movement trajectory of the physical robot. The contribution of this work is the use of genetic algorithms for path planning of robots, which enables trajectory optimization of mobile robots by reducing the error in the movement trajectory of physical robots through the interaction of virtual and real data. It provides a method to map learning in the virtual domain to the physical robot.

Coming Out, Going Home

Despite the historical centrality of Western cities as sites of queer cultural settlement, larger global economic and political forces have vociferously shaped, dispersed, and altered dreams of mobility for gay Taiwanese millennials in the age of globalization. While Taiwanese gay millennials follow a seemingly universal “rural-to-urban,” “East-to-West” movement trajectory, this study also explicates local nuanced ramifications running against the common trend. Drawn upon five-year ethnographic studies in Taiwan, this study examines how parents could to some extent conform to societal pressures by co-creating a life narrative to the society. Parents/family appear to contribute to how participants' decision on spatial movement but gay male millennials with supportive parents are eventually “going home.” However, the concept of home is configured by multiple economic and social forces involving (1) the optimal distance with the biological family and (2) the proper performances of consumption policed and imposed by the gay community in the neoliberal Taiwanese society.

Even well-practiced movements benefit from repetition

Professional golf players spend years practicing, but will still perform one or two practice swings without a ball before executing the actual swing. Why do they do this? In this study we tested the hypothesis that repeating a well-practiced movement leads to a reduction of movement variability. To operationalize this hypothesis, participants were tested in a center-out reaching task with four different targets, on four different days. To probe the effect of repetition they performed random sequences from one to six movements to the same target. Our findings show that, with repetition, movements are not only initiated earlier but their variability is reduced across the entire movement trajectory. Furthermore, this effect is present within and across the four sessions. Together, our results suggest that movement repetition changes the tradeoff between movement initiation and movement precision.

A Mobile Robot with Omnidirectional Tracks—Design and Experimental Research

This article deals with the design and testing of mobile robots equipped with drive systems based on omnidirectional tracks. These are new mobile systems that combine the advantages of a typical track drive with the advantages of systems equipped with omnidirectional Mecanum wheels. The omnidirectional tracks allow the robot to move in any direction without having to change the orientation of its body. The mobile robot market (automated construction machinery, mobile handle robots, mobile platforms, etc.) constantly calls for improvements in the manoeuvrability of vehicles. Omnidirectional drive technology can meet such requirements. The main aim of the work is to create a mobile robot that is capable of omnidirectional movement over different terrains, and also to conduct an experimental study of the robot’s operation. The paper presents the construction and principles of operation of a small robot equipped with omnidirectional tracks. The robot’s construction and control system, and also a prototype made with FDM technology, are described. The trajectory parameters of the robot’s operation along the main and transverse axes were measured on a test stand equipped with a vision-based measurement system. The results of the experimental research became the basis for the development and experimental verification of a static method of correcting deviations in movement trajectory.

Building Virtual Scene Construction and Environmental Impact Analysis Based on Image Processing

With the rapid development of computer technology, the virtual scene construction technology of image processing has gradually become a hotspot in computer research. The application of virtual scene construction technology in the construction industry is also expanding, with the intelligentization of architectural design and construction. With the rapid development of the industry, virtual technology can better provide users with diversified services and experiences. The main content of the article is as follows: (1) The article introduces image construction technology and analyzes the three-dimensional presentation of virtual technology in construction design and the diversified application of virtual technology in construction design. (2) The article introduces two virtual scene construction techniques: one is to combine the real scene obtained by taking pictures with the virtual scene by image technology processing to construct a natural virtual scene; the other is the use of geometric construction by architects. The virtual building model is drawn by the model method, and the virtual building model is thus obtained. (3) The article chooses two representative buildings as cases. The virtual platform monitors and records the movement trajectory of volunteers in the virtual environment in real time. The experimental results show that the number and shape characteristics of the escalators in the building all have a little impact on volunteers’ awareness. (4) The article sets up three control groups of normal mode, fixed skin, and variable skin. It analyzes the environmental impact of buildings from three different aspects of wind environment, thermal environment, and light environment and proposes related control measures.

Kinematic projection in modern technologies

The trajectories and coordinates of unmanned aircrafts spatial location determination is researched with the help of kinematic projection means. The methodology offered below considers the formation of two mobile and independent kinematic projection centers raised into the air by drones. The electromagnetic radio waves emitted by them, penetrating an unknown aircraft object, form two independent projecting rays intersecting at the searched aircraft location point. In this case, the searched object spatial location instantaneous (at a certain point in time) point will be placed on an imaginary “picture plane” on a line connecting the points projections generated by drones interceptors projecting rays. As far as all of the projection objects in this case are movable, all the moving trajectory projection of the searched aircraft will be displayed on the monitor. The introduction of another “picture plane”, perpendicular to the main one, will help to build an axonometric mapping not only for projections, but also for the aircraft spatial movement trajectory itself. Each point of this trajectory gives an information about the “instantaneous” coordinates of the aircraft spatial location. The method of application of kinematic projection for display of a trajectory of movement and search of coordinates of moving objects is described. In kinematic projection, all its key components, namely the object, the center of projection, the image plane and the projecting rays, are in continuous motion with certain speeds and accelerations. Kinematic projection deepens the field of practical application of descriptive geometry. This is confirmed by the example of practical application of kinematic projection presented in the article for improvement of remote control of tillage equipment in automated land treatment complexes. The main technical support for the practical application of kinematic projection are stationary radio towers or unmanned aerial vehicles (BPLA), such as drones. They are equipped with video cameras and electromagnetic radiation devices. This equipment serves as a center of kinematic projection. The projecting rays generated by the projection center will be received by a stationary command post (center). It is equipped with a radar system (radar) and modern computer equipment with appropriate software. This equipment, in this case, performs the function of a “picture plane”, which will reflect the trajectory of agricultural machinery. Actuators and controls of the movement of tillage equipment are equipped with receivers of control radio waves and means of automated control. The use of kinematic projection helps to improve the quality of tillage. This is ensured by the fact that its use is carried out automatically and eliminates possible errors of operators. Kinematic projection can also be used in military affairs to detect enemy drones in the airspace. In this case, use a kind of kinematic projection with its two centers of generation of projecting rays. This is an example of the solution of the so-called “inverse problem” of kinematic projection, which provides the ability to search for the coordinates of the motion of the projected object at a known trajectory of its motion. The main advantage of kinematic projection is the ability to identify and display an object on a computer screen not only in a flat view, but also taking into account its spatial coordinates.

Study on the training model of football movement trajectory drop point based on fractional differential equation

To study the landing point of the curved football track, the dynamic differential equations of the football were derived in this paper. The air resistance moment was taken into account, and the rotation axis was no longer confined to the vertical direction. We compare various soccer movement regularity of different initial angular velocity 0, in turn, using standard numerical methods to solve differential equations, the selection of the initial angular velocity of three typical 0s has been carried on the detailed numerical study, and the results show that: in the same velocity V play football, corresponding to different initial angular velocity 0, the movement of football is an obvious difference. Conclusion: For the same V = 5 + 28 + 11 m/s, when no rotation Ω 0 = 0, the trajectory of the football is the usual trajectory of the projectile. When 0 = 2 − 2 + 16 rad/s, the trajectory of the football is a typical banana ball trajectory; When 0 = 13+0+0 rad/s, the trajectory of the football shows the phenomenon of left-right fluttering, similar to the fallen leaf ball.

Trajectory Recording and Analysis System for Cockroach Robot

In this study, We design a trajectory recording and analysis system to record and analysis the changes in the movement behavior of the cockroach robot after stimulation. The external hardware of this system is an infrared touchpad as the experimental platform for the cockroach robot to crawl freely, and the infrared matrices densely distributed in the X and Y directions of the infrared touchpad are used to detect and locate the position of the cockroach robot. The cockroach robot's movement trajectory is displayed visually through the projector's interface projection on the infrared touchpad. The system software consists of three main parts: the electrical signal parameter setting module, the movement trajectory recording module, and the data analysis module. The electrical signal parameter setting module sets the stimulation parameters and configures the corresponding serial port to independently stimulate the left and right antenna and cercus of the cockroach; the trajectory recording module is used to record the trajectory of the cockroach robot through the coordinate positioning method. The data analysis module explores the change of motion behavior of the cockroach robot with time after receiving the stimulus by using the stage analysis method, and explores the change of motion of the cockroach robot with different voltage stimulus by using the module analysis method. The system is tested in experiments and the results demonstrated its applicability to the recording and analysis of the cockroach robot's trajectories.

Sensorimotor strategy selection under time constraints in the presence of two motor targets with different values

Goal-directed movements often require choosing an option from multiple potential goals under time constraints. However, there are limited studies on how humans change their time spent on decision-making and movement patterns according to time constraints. Here, we examined how sensorimotor strategies are selected under time constraints when the target values are uncertain. In the double-target condition, the values were uncertain until the movement onset and presented immediately afterwards. The behavior in this condition was compared to the single-target condition, in relation to time constraints and target-separation-angles. The results showed that the participants frequently used the choice-reaction even under tight time constraints, and their performance was consistently lower than that in the single-target condition. Additionally, in the double-target condition, differences in the movement trajectory depending on the time constraint and target-separation angle were confirmed. Specifically, the longer the time constraint, the higher the frequency of the intermediate behavior (to initiate movement toward the intermediate direction of two targets) or the change-of-mind behavior (to change the aiming target during movement). Furthermore, the smaller the target-separation angle, the higher the frequency of intermediate behavior, but the frequency of change-of-mind was not affected by the target-separation angle. These results suggest that the participants initiated the movement at an incomplete value judgment stage in some trials. Furthermore, they seemed to select a strategy to utilize the information obtained during the movement, taking into account the time constraints and target-separation angle. Our results show a consistent cognitive bias in choosing a higher value when multiple alternatives have different values. Additionally, we also suggest flexibility and adaptability in the movement patterns in response to time constraints.

Multi-Angle Fusion-Based Safety Status Analysis of Construction Workers

Hazardous accidents often happen in construction sites and bring fatal consequences, and therefore safety management has been a certain dilemma to construction managers for long time. Although computer vision technology has been used on construction sites to identify construction workers and track their movement trajectories for safety management, the detection effect is often influenced by limited coverage of single cameras and occlusion. A multi-angle fusion method applying SURF feature algorithm is proposed to coalesce the information processed by improved GMM (Gaussian Mixed Model) and HOG + SVM (Histogram of Oriented Gradient and Support Vector Machines), identifying the obscured workers and achieving a better detection effect with larger coverage. Workers are tracked in real-time, with their movement trajectory estimated by utilizing Kalman filters and safety status analyzed to offer a prior warning signal. Experimental studies are conducted for validation of the proposed framework for workers’ detection and trajectories estimation, whose result indicates that the framework is able to detect workers and predict their movement trajectories for safety forewarning.