Design Of Robotic Arm Research Articles

Design of an affordable IoT open-source robot arm for online teaching of robotics courses during the pandemic contingency

This article explains the design and construction of an affordable, open-source robot arm for online teaching of robotics courses. The main goal of the proposed robotic prototype is to deal with the current situation of pandemic contingency, where students and instructors cannot attend laboratory facilities in person. The robotic system has four main components: an electromechanical robot arm structure, a control system, a Wi-Fi communications module, and a human-machine interface. The IoT (Internet of Things) robot arm can be used to demonstrate important robotics topics such as direct and inverse kinematics, which are shown by programming simple and complex motions using the Denavit-Hartenberg (DH) methodology. The capabilities of the robotic system are empowered by IoT technology, which is demonstrated with an HMI interface deployed in a smartphone using wireless Wi-Fi communication through an ESP32 microcontroller. The arm's purpose is to be a low-cost and replicable robot that aids the comprehension of robotics design through project-based learning, from the theoretical aspects to the actual coding and construction of a prototype.

Design and Development of Bio-Sensitive Robotic Arm using Gesture Control

In this paper, a model of a robotic arm is designed and manufactured using a 3D printer, which is to be operated via human gesture by using the Accelerometer and Gyroscope Module. This arm is proposed to help in the medical field, in military operations, in hazardous conditions and in industries to maximize human safety. The robot arm is designed such that, it has 5 degrees of freedom controlled by the 3-axis accelerometer mounted on the IC placed on the glove of the user. The module will replicate the movement of the user’s hand to extend, retract, and rotate accordingly to accurately position as required for the application. The user’s finger action is used to manipulate the working of the gripper. Therefore, gesture control in a broad sense is a computerized interface that allows computers to record and interpret those gestures into commands to adhere to actions.

Humanoid gesture control arm with manifold actuation using additive manufacturing

The design and implementation of humanoid gesture control robotic arm with multiple actuations is proposed. Utilization of gesture based design is made here. The design is made such a way that five separate movable fingers, flexion and extension installed wrist with tilt feature. Human palm movements are imitated in robotic arm using the motion glove. To develop the processing of arms with additional movement, to improve the aesthetics both for the safety and to look as less artificial. Already in this field metallic and plastic variants are used. The dimensions are made with the help of human palm dimensions. A human design is not sufficient. It also need the movements that is done by actual human [1]. This paper we propose the number of movements done by the arm is made to 120 [2].

The Design and Implementation of a Single-Actuator Soft Robot Arm for Lower Back Pain Reduction

This paper presents a simple and fast design and implementation for a soft robot arm. The proposed continuum arm has been built by a single self-bending contraction actuator (SBCA) with two-fingers soft gripper. Because of the valuable advantages of the pneumatic artificial muscle (PAM), this continuum arm provides a high degree of safety to individuals. The proposed soft robot arm has a bending behaviour of more 180° at 3.5 kg, while, its weight is 0.7 kg. Moreover, it is designed to assist the people by reducing the number of backbends and that leads to a decrease in the possibility of lower back pain.

An Economical Robotic Arm for Playing Chess Using Visual Servoing

The proposed paper outlines the design of an economical robotic arm which is used to visualize the chess board and play with the opponent using visual servoing system. We have used the FaBLab RUC's mechanical design prototype proposed and have further used Solidworks software to design the 4 jointed gripper. The proposed methodology involves detecting the squares on the corners of the chessboard and further segmenting the images. This is followed by using convolutional neural networks to train and recognize the image in order to determine the movement of the chess pieces. To trace the manipulator, Kanade-Lucas-Tomasi method is used in the visual servoing system. An Arduino uses Gcode commands to interact with the robotic arm. Game Decisions are taken with the help of chess game engine the pieces on the board are moved accordingly. Thus a didactic robotic arm is developed for decision making and data processing, serving to be a good opponent in playing chess.

Design and Control of Pneumatic Muscle-Driven Robot Arm Based on Bilateral Rehabilitation Training

As a new treatment method, the upper limb rehabilitation training robot can help stroke hemiplegic patients recover their upper limb motor function by providing repetitive exercises and other ways. In this paper, based on the background of bilateral rehabilitation training with pneumatic muscle-driven robot arm containing paw system, the key technology of benevolence is systematically studied, and a set of experimental system is designed to verify the research results in detail. The mechanism design of the humanoid multi-joint double-arm is completed by imitating the human arm. Pneumatic artificial muscles are used to drive the shoulder and elbow joints of the mechanical arm, and stepping motors are used to drive auxiliary motion joints. The designed mechanical arm has both flexibility and compactness in structure. This study provides a useful reference for improving the effectiveness of arm design of upper limb rehabilitation pneumatic muscle-driven robot, and is helpful to broaden the research ideas of upper limb rehabilitation robot.

Parameter Estimation of a Friction Model for a Tendon-sheath Mechanism

Mechanical systems using tendon-driven actuators have been widely used for bionic robot arms because not only the tendon based actuating system enables the design of robot arm to be very efficient, but also the system is very similar to the mechanism of the human body’s operation. The tendon-driven actuator, however, has a drawback caused by the friction force of the sheath. Controlling the system without considering the friction force between the sheath and the tendon could result in a failure to achieve the desired dynamic behaviors. In this study, a mathematical model was introduced to determine the friction force that is changed according to the geometrical pathway of the tendon-sheath, and the model parameters for the friction model were estimated by analyzing the data obtained from dedicated tests designed for evaluating the friction forces. Based on the results, it is possible to appropriately predict the friction force by using the information on the pathway of the tendon.

Design and Static Analysis of Robotic Arm using Ansys

In this paper, analysis and exploration is done of the stresses and total deformation incited for a specific payload of a robot. A five degree of freedom (DOF) robot arm has been selected for stress and deformation evaluation. The design and model of the five DOF robot arm has been fabricated by Solid works and the whole structure evaluation has been executed by ANSYS software. In present world, robots are used in different fields especially where accuracy is needed. A model design development methodology utilizes the finite element analysis (FEA) for designing the robotic arm. In the past few years, the modelling, construction, and evolution of robot arm have been very dynamic research fields all over the world. In this paper, the simulation of a robotic arm is done with the help of ANSYS software, and many systemic aspects of a robotic arm are explored. The main purpose is the evolution of a design which has the ability to guessing the robot arm precision, under definite arm postures and maximum stress circumstances. Dissimilar nozzle weights are forced, and final data at various situations are equated to discover the feeble portions, so further structure upgrading should be possible.

Design, fabrication, modeling and control of a fabric-based spherical robotic arm

In this paper we present a spherical soft robotic arm made from fabric. The inflatable arm has a small mass and is pneumatically actuated. A configuration is employed with only three actuators controlling the two rotational degrees of freedom of a spherical joint. This differs from the commonly employed antagonistic pairs, including four actuators for two degrees of freedom. The fabrication procedure of the lightweight and compliant system is discussed in detail and uses commonly available materials and tools. The capability of the robotic arm to adjust the joint stiffness as a function of the actuator pressures is investigated and characterized for different deflection directions. The static mapping from the actuator pressures to the orientation of the robotic arm is identified from data and the inverse mapping is employed in a position controller. The modeling and controller derivation are performed for three different stiffness levels demonstrating the ability of the spherical robotic arm to change the joint stiffness independently of controlling the position. The position tracking performance is experimentally evaluated by tracking a square trajectory. A comparison of the tracking performance for the different stiffness levels shows that accurate tracking is more challenging for the smallest joint stiffness. A gray-box model capturing the interactions of the two degrees of freedom is used in a learning scheme that is applied for the smallest stiffness level. The learning approach reduces interactions between the two degrees of freedom and demonstrates the control performance achievable with the system developed.

Worst case identification based topology optimization of a 2-DoF hybrid robotic arm

In the design of robotic arms, structural topology optimization considering variable configurations with high computational efficiency is still a challenging issue. In this paper, the worst case identification based topology optimization of a 2-DoF hybrid robotic arm is accomplished, and the presented work mainly covers: (1) efficient worst case identification; (2) optimization problem construction and (3) iterative criterion and filtering method with fast convergence. The forward kinematics are investigated to identify the workspace. Thereafter, the equivalent external load is proposed to unify the effect of axial load and shear by force analysis and compliance calculation. The worst case is the load case with maximum compliance and can be located efficiently by searching for the maximum equivalent external load. The optimization problem is constructed based on the solid isotropic material with penalization (SIMP) interpolation scheme. For links with multiple worst cases, the objective function is constructed as the weighted sum of compliance under each worst case. For better computational efficiency, the modified guide-weight method is used to solve the optimization problem. To eliminate the mesh dependence and checkerboard problem, a guide weight filtering method is proposed. Under the guidance of derived optimal topology, the CAD model of the hybrid robotic arm is presented. The effect of the optimization is testified through performance comparison in finite element analysis. The optimization method can derive the optimal topology with global validity within allowable computational time and the optimization approach can be applied to other hybrid robotic arms as well.

New Insights on the Control and Function of Octopus Suckers

Octopuses utilize their suckers for a myriad of functions such as chemo‐ and mechanosensing, exploring and manipulating objects, anchoring the body during crawling, and navigating through narrow passages. The sucker attachment mechanism grants the octopus the ability to perform many of these tasks. The goal of this study is to analyze sucker function and control through the assessment of pull‐off forces under different conditions. Sucker pull‐off forces are measured in Octopus bimaculoides (three females, seven males), when the arm is intact, amputated, and amputated with the suckers punctured. Greater sucker pull‐off forces are observed for amputated arms, plausibly indicating that the brain and/or the interbrachial commissure are responsible for triggering early sucker detachment in the intact animal. In addition, after piercing and compromising the sucker cavity, pull‐off force significantly decreases, indicating that the primary mechanism for sucker attachment is suction, and is less dependent on adhesion. These results provide new insights into the control and function of octopus suckers that can be integrated into the design and development of soft robot arms for aquatic applications.

Novel design and kinematic analysis of a 5-DOFs robotic arm with three-fingered gripper for physical therapy

This paper presents the design and kinematic analysis of a novel robotic arm for the automation of manual operations performed by physiotherapists. Conventionally, a repetitive task is performed to visualize inflamed tendons, joints and ligaments with many patients. Therapeutic ultrasound techniques are further used to heal them by efficient energy transfer. During both, visualization and healing process, physiotherapists move the hand-held transducer knob for a set of specified trajectories. To perform such actions, a dedicated robotic arm can reduce manual working hours of physiotherapists and relax them. In this work, a 5-degrees of freedom (DOFs) robotic arm with three-fingered gripper is designed and modeled in SolidWorks software. The design specifications of the robotic arm are decided in accordance with therapist’s arm and available ultrasonic therapy unit of institute hospital. The detailed forward, inverse, and velocity kinematic analysis of the robotic arm are presented using Denavit-Hartenberg (D-H) parameters and Jacobian matrix. From the simulation runs in MATLAB, the joint variables and joint angular velocities are estimated for a specified set of trajectory responses viz., spiral and lemniscate curves in the x-y plane. A set of specified trajectories is selected in consultation with the institute physiotherapist. Furthermore, the linear and angular velocities of the end-effector are estimated using velocity kinematics. The smooth and small magnitude of variation in joint angles, joint angular velocities and end-effector linear and angular velocities establishes a framework for reliable design.

Design of Rover and Robotic Arm

A 4-wheel independent drive rover is designed, engineered and built. The rover suspension is made to cope with the adverse conditions of all terrains making it reliable to navigate and explore an alien planet like Mars. The robotic arm is also designed and manufactured with six degree of freedom which is useful to assist the rover for multiple purposes such as to collect the soil samples for testing, to open and close the taps or valves and also to assist the astronaut for picking up tools like screwdriver, cutting player, etc. during an emergency.

Robotic technology towards industry 4.0: Automatic object sorting robot arm using kinect sensor

As one of the most commonly employed robots in manufacturing business, robot arm has to develop into a technology capable of successing the industry 4.0 revolution. A robot arm that can interact well with humans to solve a problem becomes one of the encouraging research topics. It requires the ability to behave like humans which causes a robot arm should be utilizing intelligent peripherals. This study aims to create a robot arm design that uses a Kinect sensor as a smart peripheral to approach the human ability to see an object. As a case study, a color-based object sorting simulation was conducted. The automatic movement that the robot used is based on inverse kinematics. The experimental test shows that average percentage errors for end-effector’s position in x, y and z coordinates are 5.83%, 5.89% and 8.59%, respectively. This result has led the robot arm equipped with the Kinect sensor managed well to sort and move objects based on the color.

Integrated structure/control design of high-speed flexible robot arms using topology optimization

Most robotic applications demand lightweight and high-speed manipulators for considerably reducing the consumed power and achieving high production rates. The two ways for seeking such high-speed arms are; applying advanced control algorithms and/or performing an extensive optimization of the arm structure itself. Therefore, the topology optimization technique is proposed here for obtaining an optimal robot arm design from both structure and control viewpoints. Results of some researches, that have been previously accomplished by size and shape optimization, were encouraging enough to extend and propose this optimization approach. The method of moving asymptotes (MMA) as an optimization algorithm, the finite element analysis (FEA) by ANSYS, and the time-optimal control method are integrated to gain an optimum design capable of attaining the minimum traveling time. The proposed methodology focuses on performing different comparisons between the proposed optimum topological designs and their initial designs for different robot arms’ sizes and materials. It also distinguishes between the proposed optimum design and the previously achieved one by size optimization under the same operational conditions. Therefore, the significance of the proposed technique is emphasized. It shows that the traveling time is reduced by 44.8%, while the previous work only achieved 23.5%. In addition, the mass is reduced to nearly half of its initial value, taking into account the air damping as the real case in all terrestrial applications.

A generalizable equilibrium model for bending soft arms with longitudinal actuators

Current models of bending in soft arms are formulated in terms of experimentally determined, arm-specific parameters, which cannot evaluate fundamental differences in soft robot arm design. Existing models are successful at improving control of individual arms but do not give insight into how the structure of the arm affects the arm’s capabilities. For example, omnidirectional soft robot arms most frequently have three parallel actuators, but may have four or more, while common biological arms, including octopuses, have tens of distinct longitudinal muscle bundles. This article presents a quasi-static analytical model of soft arms bent with longitudinal actuators, based on equilibrium principles and assuming an unknown neutral axis location. The model is presented as a generalizable framework and specifically implemented for an arm with fluid-driven actuators, a subset of which are pressurized to induce a bend with a certain curvature and direction. The presented implementation is validated experimentally using planar (2D) and spatial (3D) bends. The planar model is used to initially estimate pressure for a closed-loop curvature control system and to bound the accessible configurations for a rapidly-exploring random trees (RRT) motion planner. A three-segment planar arm is demonstrated to navigate along a planned trajectory through a gap in a wall. Finally, the model is used to explore how the arm morphology affects maximum curvature and directional resolution. This research analytically connects soft arm structure and actuator behavior to unloaded arm performance, and the results may be used to methodically design soft robot arms.

Design and Construction of a Cost-Effective Didactic Robotic Arm for Playing Chess, Using an Artificial Vision System

This paper presents the design and construction of a robotic arm that plays chess against a human opponent, based on an artificial vision system. The mechanical design was an adaptation of the robotic arm proposed by the rapid prototyping laboratory FabLab RUC (Fabrication Laboratory of the University of Roskilde). Using the software Solidworks, a gripper with 4 joints was designed. An artificial vision system was developed for detecting the corners of the squares on a chessboard and performing image segmentation. Then, an image recognition model was trained using convolutional neural networks to detect the movements of pieces on the board. An image-based visual servoing system was designed using the Kanade–Lucas–Tomasi method, in order to locate the manipulator. Additionally, an Arduino development board was programmed to control and receive information from the robotic arm using Gcode commands. Results show that with the Stockfish chess game engine, the system is able to make game decisions and manipulate the pieces on the board. In this way, it was possible to implement a didactic robotic arm as a relevant application in data processing and decision-making for programmable automatons.

Design and Development of an Educational 5-DoF Robotic Arm

The effective training of engineering students require hands-on experience in what they would later work with in the industry. The trend in manufacturing nowadays is towards robotics and automation. Relevant to this technology is the robotic hand. This paper outlines the design and the development of a 5-DoF (Degree of Freedom) robotic arm. The robotic arm is intended for educational purposes. The design proposed the use of servos to power the joints and to implement the inverse kinematics of the robotic arm. A simulation of the robotic arm was achieved by using the Matlab Robotics Toolbox, to visualise the joint movements. A suitable servo controller was selected for the implementation and a control software for the robotic arm was developed using Microsoft's C# programming language. The software allows the robotic arm gripper to be postioned in space, by specifying the coordinates of its centre position. Polymethyl methacrylate was selected to fabricate the components of the robotic arm. The robotic arm was tested by specifying various coordinates for the gripper with reference to the robot's base and measuring the corresponding coordinates of the centre position of the gripper, which gave satisfactory results.

Design and Modeling of an Extensible Soft Robotic Arm

Soft robotic arms are receiving more and more attention for their intrinsic safety and natural compliance. Instead of traditional serialized rotary joints, soft robotic arms often have complex joints with coupled degrees of freedom like bending, rotation, and elongation, enabling them with more freedoms in achieving sophisticated movements. However, currently soft robotic arms are mostly focusing on bending and rotation, whereas elongation is either unavailable due to the inextensible backbone or only has a small range because of the limited contraction ratio of actuators. Furthermore, the coupling of actuators and complex structure makes the modeling and control hard. In this letter, we introduced an extensible soft robotic arm with a large elongation ratio of 400%, and give a novel modeling method from a new perspective of the force balance of the arm. The models were experimentally tested both in loaded and unloaded situations, showing the effectiveness of predicting the bending, rotation, and elongation of the arm.

Design and development of a 5R 2DOF parallel robot arm for handling paper pot seedlings in a vegetable transplanter

This paper presents a complete mechatronic approach in designing and developing a robotic arm for handling paper pot seedlings in a transplanter for the purpose of inclusion of automation and possible reduction of heavy mechanical components in pot seedling transplanters by utilizing microcontrollers and embedded systems. The robot arm developed was of two degrees of freedom (DOF), five revolute joints (5R) with parallel arm structure using 3D printed parts, commercially available embedded microcontrollers and sensors. The gripper which was connected to the parallel robot arm performed pick and place operations at a desired path. For achieving the preferred maximum and minimum reach of the gripper, a suitable method for synthesizing the link length has been discussed. A complete logical technique to program microcontrollers was developed which enabled smooth actuation of both the independent input links simultaneously. Parabolic blends were utilized at the beginning and at the end of the robot input joint trajectory for minimizing dynamic vibrations during continuous operation. The developed robot arm was flexible to change the number of pickup points in a row, pickup and drop co-ordinates within the workspace envelope. Finally, the robot arm was tested and evaluated for picking and placing 15 numbers (4 replications, 60 runs) of actual paper pots filled with vermicompost, soil and sand. Each pot weighed approximately 80 g with a moisture content of approximately 5%. The robot arm took 2.1 to 2.4 s to pick and drop a pot seedling from a distance of 116.6 mm with a maximum power consumption of 20.47 W. Experimental results showed that no pots were missed in picking and dropping, no visual cracks and damage appeared on the pots. The repeatability of the robot arm was 2.1 mm in X-axis and 3.4 mm in Y-axis.