Part Of Robot Research Articles

Higher Efficient Fruit Robot with Improved End Effectors

Under the situation that the technology level is improving recent year and the labor cost is increasing rapidly. In this paper, an autonomous harvesting robot with high efficiency is presented. The robot needs a fruit harvesting process with high obstacle avoidance efficiency for picking in complex and unstructured environments. In this research, the end-effector of the robotic arm picking process is optimized to reduce the number of times the fruit is crushed and to obtain the nearest moving trajectory to improve the picking efficiency. Therefore, the research topic of this paper is to optimize the picking method of the picking robot when performing picking operations. The following describes this paper's research methodology: first, the mechanical part of this harvesting robot is modeled, and then the most efficient way of the robot arm is found by analyzing the data of this model and combining it with the existing research. In this paper, it was found that changing the robotic arm's end-effector to a cylinder with a cutting blade would not only maximize the efficiency of the arm, but also ensure that the fruit would not be scratched. From this study, it was concluded that the end-effector can be customized to ensure efficient fruit picking according to the type of fruit and the approximate growth of the orchard fruit.

Design and Implementation of Omnidirectional Mobile Robot for Materials Handling among Multiple Workstations in Manufacturing Factories

This paper introduces the mechanical design and control system of a mobile robot for logistics transportation in manufacturing workshops. The robot is divided into a moving part and a grasping part. The moving part adopts the mecanum wheel four-wheel-drive chassis, which has omnidirectional moving ability. The mechanical system is based on four mechanical wheels, and a modular suspension mechanism is designed. The grasping part is composed of a depth camera, a cooperative manipulator, and an electric claw. Finally, the two are coordinated and controlled by computer. The controller hardware of the mobile platform is designed, and the functional modules of the mobile platform are designed based on the RT thread embedded system. For the navigation part of the mobile robot, a fuzzy PID deviation correction algorithm is designed and simulated. Using the Hough circular transform algorithm, the visual grasping of the manipulator is realized. Finally, the control mode of the computer-controlled manipulator and the manipulator-controlling mobile platform is adopted to realize the feeding function of the mobile robot, and the experimental verification is carried out.

Iterated-local-search-based chaotic differential evolution algorithm for hybrid-load part feeding scheduling optimization in mixed-model assembly lines

PurposeDriven by sustainable production, mobile robots are introduced as a new clean-energy material handling tool for mixed-model assembly lines (MMALs), which reduces energy consumption and lineside inventory of workstations (LSI). Nevertheless, the previous part feeding scheduling method was designed for conventional material handling tools without considering the flexible spatial layout of the robotic mobile fulfillment system (RMFS). To fill this gap, this paper focuses on a greening mobile robot part feeding scheduling problem with Just-In-Time (JIT) considerations, where the layout and number of pods can be adjusted.Design/methodology/approachA novel hybrid-load pod (HL-pod) and mobile robot are proposed to carry out part feeding tasks between material supermarkets and assembly lines. A bi-objective mixed-integer programming model is formulated to minimize both total energy consumption and LSI, aligning with environmental and sustainable JIT goals. Due to the NP-hard nature of the proposed problem, a chaotic differential evolution algorithm for multi-objective optimization based on iterated local search (CDEMIL) algorithm is presented. The effectiveness of the proposed algorithm is verified by dealing with the HL-pod-based greening part feeding scheduling problem in different problem scales and compared to two benchmark algorithms. Managerial insights analyses are conducted to implement the HL-pod strategy.FindingsThe CDEMIL algorithm's ability to produce Pareto fronts for different problem scales confirms its effectiveness and feasibility. Computational results show that the proposed algorithm outperforms the other two compared algorithms regarding solution quality and convergence speed. Additionally, the results indicate that the HL-pod performs better than adopting a single type of pod.Originality/valueThis study proposes an innovative solution to the scheduling problem for efficient JIT part feeding using RMFS and HL-pods in automobile MMALs. It considers both the layout and number of pods, ensuring a sustainable and environmental-friendly approach to production.

An Overview of Flexible Jointed Robots

Background: Since the first industrial robots were created in the middle of the last century, robotics has shown strong growth prospects. Robotics has developed rapidly over time and is being used in more and more areas. Because of the need to minimize impact forces during robot movement, traditional rigid robots are no longer sufficient, flexible joints are more adaptable to the environment due to their adjustable stiffness and have higher application value in humancomputer interaction. Therefore, flexible jointed robots have become one of the research hotspots in recent years. Objective: Through a detailed analysis of the existing hardware and software control technologies of flexible joint robots, referring to papers and recent patents on flexible jointed robots, we aim to find ways to reduce the impact of flexible joint deformation of flexible joint robots and improve the overall force and position control accuracy of flexible joint robots. Methods: To categorize the hardware and software technologies of flexible jointed robots, to briefly explain the directions of the technologies categorized and to study them, to summarize the advantages and disadvantages of each type of technology respectively, and to outlook the future development trend. Results: Through the study and analysis of the various parts of the flexible joint robot, it can be seen that joint flexibility is mainly achieved through the drive motor and flexible components to achieve flexibility and then through the fusion control technology to control the deformation of the joint. Differences in structural materials affect the mechanical properties of robot motion. The detection and feedback accuracy of the sensor also has a significant impact on the control accuracy. Conclusion: The use of new motor technology, flexible component technology, material technology, and sensor technology, combined with improvements in software fusion control technology can reduce the impact of joint deformation, improve the control accuracy of joint flexibility, and achieve high-precision force-level control capability of flexible joint robots.

Control Algorithms for a Bidirectional Wireless Power Transmission System at the Redistribution of Energy Resources in a Group of Ground Robots

Redistributing energy resources within a group of ground robots allows for an increase in the reachable workspace area and expands its functional capabilities. The use of wireless energy transfer systems for exchanging energy resources between ground robots reduces the requirements for positioning accuracy and enhances the reliability of the robotic system. This study examines control and management algorithms for a bidirectional wireless energy transfer system when operating as part of a ground robot. A structural diagram of the bidirectional wireless energy transfer module is proposed for integration into the robot’s control system, built on distributed principles. The developed algorithms take into account the specific features of the circuitry solutions of the bidirectional wireless energy transfer system, implemented using an uncontrolled resonant generator. The proposed solutions are tested on a robotics platform. The experiments focus on the process of replenishing the energy resources of one robot with another robot. Energy is transmitted between robots equipped with the same Li-ion battery, which has a nominal voltage of 7.4 V and a capacity of 5 A•h. The battery is charged from 50 % to 90 % capacity with different positioning accuracies of the robots. When there is a displacement of 4 mm and a distance of 4 mm between the receiving and transmitting coils, the charging time was 48 minutes, which is 5 % longer than the wired charging method. The maximum charging time reached 57 minutes with a distance of 15 mm between the robots. The use of bidirectional wireless power transfer for energy exchange between ground robots or for charging robots at a charging station enhances the autonomy of the group’s operation, as energy transfer can be successfully achieved even with low positioning accuracy. The proposed solutions can be used for battery charging and resource redistribution processes in groups of ground and underwater robots.

The effect of ionizing radiation on robotic trajectory movement and electronic components

Robotics applications are greatly needed in hazardous locations, e.g., fusion and fission reactors, where robots must perform delicate and complex tasks under ionizing radiation conditions. The drawback is that some robotic parts, such as active electronics, are susceptible to radiation. It can lead to unexpected failures and early termination of the robotic operation. This paper analyses the ionizing radiation effect from 0.09 to 1.5 Gy/s in robotic components (microcontrollers, servo motors and temperature sensors). The first experiment compares the performance of various microcontroller types and their actuators and sensors, where different mitigation strategies are applied, such as using Radiation-Hardened (Rad-Hard) microcontrollers or shielding. The second and third experiments analyze the performance of a 3-Degrees of Freedom (DoF) robotic arm, evaluating its componentsʼ responses and trajectory. This study enhances our understanding and expands our knowledge regarding radiationʼs impact on robotic arms and components, which is useful for defining the best strategies for extending the robotsʼ operational lifespan, especially when performing maintenance or inspection tasks in radiation environments.

Path planning of mobile robots in dynamic environment based on analytic geometry and cubic Bézier curve with three shape parameters

With the improvement of technology, autonomous mobile robots have become an indispensable part of human life. Since path planning is the crucial part of mobile robots, these paths should be feasible, smooth and collision-free in a certain environment. However, forming desirable paths in a dynamic environment with static and moving obstacles is still a problem in the literature. In this paper, we present a new approach based on the analytic geometry for collision avoidance and the cubic Bézier curve with three shape parameters to obtain global and local paths in a dynamic environment. In this study, the environment for the mobile robot is considered to be a square plane without a grid consisting of several static obstacles in different geometric shapes, a mobile robot, and several dynamic obstacles in the shape of a circle with the same size. Moreover, we expressed the influence of the shape parameters on the optimal path using the objective function defined by the path length. Also, the paths generated by the cubic Bézier curve with three shape parameters and the classical cubic Bézier curve are compared in terms of their path length.

Location of acupuncture points based on graph convolution and 3D deep learning in virtual humans

AbstractAutomatic acupoint searching is an indispensable part of intelligent acupuncture robot. Clinical practice have proofed that Dazhu, Fengmen and Xinshu, which could be located by Dazhui, are curative when these points are acupuncture. The existing methods are mainly based on regular or image. The regular‐based methods are based on the experience of physicians, and the accuracy will decrease for different patients; While the image‐based methods will lose some features in image. In order to solve the existing problems, we propose a novel graph convolution mixed with point cloud deep learning method. In this method, the skinned multi‐person linear model is regarded as a graph structure input, and the coarsened graph is obtained by graph convolution. After feeding the coarsened graph into the PointNet network, the coordinates of Dazhui are output. Different from the existing methods, the proposed method can directly label the results on the adaptive model, thus improving the accuracy on different models. An optimization method based on graph structure is introduced for better fit the predicted acupoints to the surface. In addition, a dataset marked with Dazhui is constructed for training. Experiments show that the accuracy of positioning could meet the requirements of needle application under certain circumstances.

Design of the Paw of Wall-Climbing Robot with Spiny and Sensing Function

Paws are the key parts for wall-climbing robots to climb on vertical walls. Wall-climbing robots with spiny feet have important application value in the safety monitoring of buildings, bridges, tunnels, and other buildings. Researchers have designed a variety of spiny feet that can bear large weights and have strong adaptability. However, due to the lack of robot grasp state perception, it is difficult to complete the task normally when there are obstacles and complex walls. In this paper, according to the perceptual feedback mode of the foot of the domestic cat when climbing, a kind of paw with a spiny and sensing function is designed. The paw can give real-time feedback of the gripping force, which well copes with the failure of gripping force and helps the wall-climbing robot to cope with uncertain wall environment.

Beyond Trade-Off: An Optimized Binocular Stereo Vision Based Depth Estimation Algorithm for Designing Harvesting Robot in Orchards

Depth estimation is one of the bottleneck parts for harvesting robots to determine whether the operation of grasping or picking succeeds or not directly. This paper proposed a novel disparity completion method combined with bilateral filtering and pyramid fusion to improve the issues of incorrect outputs due to the missed or wrong matching when achieving 3D position from 2D images in open-world environments. Briefly, our proposed method has two significant advantages in general. Firstly, occlusion between leaves, branches, and fruits is a universal phenomenon in unstructured orchard environments, which results in the most depth estimation algorithms facing great challenges to obtain accurate outputs in these occluded regions. To alleviate these issues, unlike other research efforts that already exist, we optimized the semi-global matching algorithm to obtain high accuracy sparse values as an initial disparity map; then, an improved bilateral filtering algorithm is proposed to eliminate holes and discontinuous regions caused by occlusion to obtain precise and density disparity outputs. Secondly, due to taking the practical high-efficiency requirements of the automated harvesting robot in its working status into consideration, we attempted to merge multiple low-resolution bilateral filtering results through the pyramid fusion model which goes beyond the trade-off mechanism to improve the performance of both accuracy and time cost. Finally, a prototype harvesting robot was designed to conduct experiments at three kinds of different distances (0.6~0.75 m, 1~1.2 m, and 1.6~1.9 m). Experiment results showed that our proposed method achieved density disparity maps and eliminated holes and discontinuous defects in the disparity map effectively. The average absolute error of our proposed method is 3.2 mm, and the average relative error is 1.79%. In addition, the time cost is greatly reduced more than 90%. Comprehensive experimental results demonstrate that our proposed algorithm provides a potential possibility for designing harvesting.

Fiqh Robotic For Artificial Intelligent In Humanoids Used For Therapy, Services And Other Social Activities: An Integration Of Artificial Intelligence (Ai) And Maqasid Shariah

Humanoid is part of the Social Assistive Robotics (SAR) which has been designed with a comprehensive artificial intelligence system that is widely used for elderly care, rehabilitation for people with physical disabilities as well as the intervention of individuals with cognitive impairment. Nowadays, with the advance of this technology, the world is also utilizing these humanoids for social activities and services. Consequently, some controversial questions amongst religious scholars, academicians, clinicians, services and societies arise on the urgency to use humanoid robots for therapy of the intervention in the brain-impairments, elderly care, rendering general services or for social companions when the world seems to adapt that humanoid is one of those modes, which shows potential in giving better outcomes. Due to the problem, there is an urgency to develop Fiqh Robotics to help the nation at large on the permissible of using humanoids used for social activities, services and rehabilitation. A qualitative method is used in analysing and synthesizing the relevant literature and document review to develop this Fiqh Robotic from the framework of Maqasid Shariah, together with the combination of accelerating rapid growth of the world Artificial Intelligence (AI, particularly discussing the measurement Humanoid Robot Interaction (HRI), Maqasid Shariah Principles, Islamic Legal Maxims and the permission of using this approach in Islam.

Prototyping and Integration of Educational Low-Cost Mobile Robot Platform

This paper describes the process of designing and prototyping a low-cost robotic platform based on existing equipment and projects that enable extracurricular STEM activities in Croatia and beyond. A robotic platform with a differential drive configuration was chosen for education from an early age due to its simplicity and a wide range of cheap and compatible components from which it can be made. From the aspect of integration into extracurricular or curricular activities, the BBC micro:bit ecosystem was considered, enabling block-based visual programming. Components with printable parts make up the assembly of the educational robot. The main steps in designing and creating a robot prototype are presented, which consist of the modelling, 3D printing of robot parts, and assembly into a functional system. After several stages of testing, an interactive workshop was held with 7th-grade primary school pupils. Further work is planned to create educational material for extracurricular STEM workshops.

BiTac: A Soft Vision-Based Tactile Sensor With Bidirectional Force Perception for Robots

Although various designs have been reported in the literature for vision-based tactile sensors, a few of them can detect pressing forces. These designs are often addressed with learning-based approaches that critically rely on training and require large amounts of training data. This study presents a novel visuotactile sensing technology for the development of large-scale vision-based tactile sensors named BiTac, which can accurately reconstruct its 3-D surface shape in real-time and is capable of detecting the bi-directional distribution of normal forces applied to its soft sensing surface. The sensor skin was made of soft and elastic materials composed of an array of markers which are tracked efficiently by a compact stereo camera, whose parameters could be calibrated automatically. Notably, the complexity of mapping the displacement fields calculated from the images to the normal force distribution is resolved by the finite element method, which would be a generalized modeling technique for soft materials. This article comprehensively covers the design, fabrication, theoretical modeling, calibration, and experiments. The hardware capability and tactile perception were assessed quantitatively and qualitatively through real interactions with various objects. With a simple structure and analytical approach, the BiTac sensor can be easily customized and manufactured for different parts of robots, making it a potential design for mass production.

Simulation Modeling of Mobile Robotic Complexes Tool Analysis According to Physical Laws (a Review)

This article is about the technologies of simulation modeling of mobile robotic complexes. The basic demands for a simulation environment are defined such as realistic results, open-source code, extensibility, performance of system, possibility of usage of low-level code for simulation. Moreover, the most significant characteristics for physics engines are described in the article, specifically solid-state physics, torque setup, stability of "axle" connection, stability of the simulated many-body system. The frequently used physics engines such as PhysX, ODE, MuJoCo, Bullet, Havok are analyzed and the search of modeling services is made in order to make the comparative table. The platform Unity is in focus of this work to show its abilities in modeling of mechanical and electronic parts of mobile robots. The aim of this work is minimizing mobile robots development outgoings. Programming product is given as result of simulation modeling of robotic complexes. The Unity platform is used as the engine for development of simulation tools for mechanical and electronic parts of robotic complex. The set of tools based on Unity engine is developed in order to create virtual models of mobile robots. The architecture of the project was developed in order to determine aspects of creating mobile robots in a simulation modeling environment. The logic of scripts for modeling the solid-state physics, kinematic chains and joints with different degrees of freedom is presented as a result of developing architecture of the project. The package was tested, a model of a mobile four-wheeled robotic platform was built as a result of the test.

Организация практико-ориентированного обучения на кафедре «Инженерная графика» РТУ МИРЭА

The article discusses the organization of practice-oriented learning at the Department of Engineering Graphics of the RTU MIREA, the essence of which is the development of not only design documentation, but also the production of a prototype device for which design documentation has been made. Geoinformatics students create 3D models of terrain objects: buildings, terrain and vegetation based on photo and video data from drones. The course project serves as the basis for a deeper study of geometric and graphic disciplines in the form of competitive works, scientific reports and publications, or can serve as the basis for the final qualification work.
 As part of the course work, students of the Institute of Radio Electronics and Informatics perform a multi-level study of an electronic device - a sensor using "smart home" technology. Not only a significant amount of design documentation is developed with the help of circuitry and design CAD: diagrams, printed circuit boards with tracing, assembly drawings, specifications and other text documents, but also a working prototype of the sensor is made.
 As part of the course work, chemists-technologists design a workshop for large- and medium-tonnage chemical production and develop a complete set of design documentation for one of the main apparatuses of this workshop. Based on the created 3D models, students print a model of the apparatus on a 3D printer.
 As part of the "Fundamentals of Design" course, some students develop design documentation and make one of the two printed circuit boards of a dog robot based on it. Another part of the students creates 3D models of robot parts and prints them on a 3D printer. Both groups jointly assemble and program a robot dog.

Two-stage multi-sensor fusion positioning system with seamless switching for cooperative mobile robot and manipulator system

The stoppage of a mobile platform is generally scheduled to feed parts for machines on production lines, such as fenced industrial robotic manipulators. A non-stop mobile robotic part feeding system can contribute to production efficiency and flexibility but contains several challenging tasks. For example, the industrial robotic manipulator needs to perceive the positions of the mobile robot accurately and robustly before grasping the supplies when the mobile robot moves around. Thus, based on the relative distance between the two robots, an interaction mode of the integrated robotic system consisting of a fixed robotic manipulator and a mobile robot is developed for robotic interaction. In order to accurately and robustly perceive the positions of a mobile robot, two different positioning approaches for the robotic manipulator positioning mobile robot in an indoor environment are utilised. One approach is ultrasonic sensors fused with inertia measurement units (IMU) by extended Kalman filter (EKF). Furthermore, an outlier rejection mechanism is implemented to escape outliers from ultrasonic measurement. Another positioning approach is achieved by detecting an ArUco marker with visual sensor. Lastly, a positioning switching strategy according to the visual sensor state allows the robotic manipulator to reposition the mobile robot seamlessly. According to the static experiments, EKF-based positioning approach fusing IMU with ultrasonic sensor can export high-accuracy (the root mean square error is 0.04 m) and high-precision (the standard deviation is 0.0033 m) in positioning while keeping a high update frequency of 181.9 HZ in static positioning. Evaluations through dynamic experiments demonstrate that the proposed positioning system can suppress the positioning drifts over time in comparison with wheel encoder-based positioning method. The two-stage repositioning strategy can support the robotic manipulator to identify the positions of the mobile robot robustly, even in the case when the visual sensor is occluded.

Soft robotic finger with variable effective length enabled by an antagonistic constraint mechanism

Compared to traditional rigid robotics, soft robotics has attracted increasing attention due to its advantages in compliance, safety, and low cost. As an essential part of soft robotics, the soft robotic gripper also shows its superior while grasping objects with irregular shapes. Recent research has been conducted to improve grasping performance by adjusting the variable effective length (VEL). However, the existing VEL function achieved by mechanisms such as multi-chamber design or tunable stiffness shape memory material requires a complex pneumatic circuit design or a time-consuming phase-changing process. This work proposes a fold-based soft robotic finger with VEL function from 3D printing. It is experimentally tested and modeled by the hyperelastic material property. Mathematic and finite element modeling is conducted to study the bending behaviour of the proposed soft actuator. Most importantly, an antagonistic constraint mechanism is proposed to achieve the VEL, and the experiments demonstrate that better conformity is achieved. Finally, dual-mode grippers are designed and evaluated to demonstrate the advances of VEL on grasping performance.

Perspective Of Vision, Motion Planning, And Motion Control for Quadruped Robots

In recent years, robot technology has made great progress, especially quadruped robots. Quadruped robot is a bionic robot that imitates the movement of quadruped animals. For quadruped machines in complex environments, our group first investigate the control of quadruped robots in complex situations. It is found that the current quadruped robots can achieve better motion control under various complex conditions, but there are still limitations. Its structure includes the trunk and four legs located in front and behind the trunk. Each leg has the same structure, including the thigh, calf, and foot. This paper summarizes the research on foot structure design and foot tip trajectory optimization of quadruped robot. Machine Vision is a branch of artificial intelligence that is developing rapidly. Simply put, machine vision is to use machines instead of human eyes to make measurements and judgments. The following passage discusses about two main kinds of algorithm, while making analytic and comparisons among others and why to choose these two out in the machine vision part of quadruped robots. By summarizing and analyzing the research status, this paper proposes some challenging and valuable future research directions.

Sensor Fusion using Model Predictive Control for Differential Dual Wheeled Robot

Every mobile robot mission starts with the robot being moved to the task site. From there, the robot executes its tasks. A control system is required to move the mobile robot's actuator (which may be in the shape of wheels or legs) and comprehend the environment around the robot to perform these movements (perception). This research aims to develop a technique to control a robot’s movement while detecting obstacles and distances toward an object. The robot is equipped with LIDAR and a camera to perform these tasks. The control is divided into two major parts, low-level and high-level controller. As part of a low-level controller robot, the Model Predictive Control (MPC) method is proposed to help with the control of the wheel while the Artificial Neural Network (ANN) approach to use in this study to identify obstacles and the Convolutional Neural Network (CNN) method for detecting objects, both ANN and CNN as a control for high-level part of the robot. The results of this study can prove that CNN can help detect existing objects with a value of 45% for detecting some objects. The obtained result from the MPC method, which has been combined with an ANN as an obstacle detector, is that the smaller the horizon value, the shorter the time needed to reach the desired coordinates with the result being 45 seconds.

Three birds with one stone: Design and synthesis of polyurethane actuator for executing heat, light and humidity triggered deformation

Intelligent actuation materials are widely utilized as parts of soft robots, smart sensors and other applications, due to their response to external stimuli (such as heat, light, magnetism, humidity, etc.). Yet preparing a single polymer material with multi-stimuli responsive functions remains challenging and less explored. Herein, we have explored a novel multi-stimuli responsive intelligent actuating polyurethane material, AzoPU50, through one-pot co-polymerization of 4,4′-bis (6-hydroxy-hexoxy) azobenzene (BHHAB), polyethylene glycol 400 (PEG400) and 4,4′-methylene bis (phenyl isocyanate) (MDI) at a ratio of 1:1:2. This novel material can respond to three types of stimuli to trigger shape deformation movements. The intrinsic microphase separation structure of polyurethane can afford thermal responsive shape memory performances. Furthermore, the variation in the configuration of azobenzene units endows the polyurethane film with good light-responsive deformation. Most importantly, this polyurethane actuator can also achieve humidity-responsive movements including flipping motion on a wet filter paper, bending deformation driven by the palm and finger, etc. In addition, a biomimetic device that integrated the heat, light and humidity stimuli together to imitate human gestures of praise was successfully assembled. This work provides a new strategy for constructing actuators with triple-functions and will pave a way for further development of multi-stimuli-responsive smart actuating devices and other intelligent materials/systems.