Robotics
B. Sarikhani; M. A. Ahmadi-Pajouh; A. Kolivand; F. Bakhtiari-Nejad
Abstract
The hand plays a crucial role in daily activities; injury or paralysis significantly reduces independence. Therefore, robotic hand exoskeletons have been developed to restore motor function safely and effectively. Considering the major role of the hand in daily activities, many researchers have been ...
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The hand plays a crucial role in daily activities; injury or paralysis significantly reduces independence. Therefore, robotic hand exoskeletons have been developed to restore motor function safely and effectively. Considering the major role of the hand in daily activities, many researchers have been working on hand rehabilitation exoskeletons. This research presents the design and implementation of a tendon-driven exoskeleton for finger rehabilitation. Continuous passive motion devices are used to maintain and restore the range of motion of the joints. The exoskeleton has been designed to help patients easily perform functional tasks. To achieve this goal, an adjustable thimble mechanism with flexible filament and a finger guide was designed. Also, this design provides the necessary force to fully guide the fingers through the whole range of motion of the joints. The designed mechanism has been modeled and simulated in MATLAB software. It has also been tested on healthy human subjects. Recorded images from the index finger in a complete range of motion have been analyzed to find the finger trajectory during flexion. The metacarpophalangeal joint of the index finger in healthy subjects has a range of motion between 0 and 90 degrees, while the exoskeleton can provide a range of motion between 0 and 94 degrees. Results show that the designed exoskeleton can provide sufficient force and an acceptable range of motion for patients up to level 2 of the Ashworth scale, which is acceptable for most different and functional varieties of continuous passive motion exoskeletons.
Robotics
Vengatesan Arumugam; Vasudevan Alagumalai
Abstract
Mobile robots have garnered significant attention across various domains, including industrial automation, healthcare, logistics, and autonomous vehicles. However, effective navigation in dynamic and complex environments remains a critical challenge. This research introduces an improved deep q-network ...
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Mobile robots have garnered significant attention across various domains, including industrial automation, healthcare, logistics, and autonomous vehicles. However, effective navigation in dynamic and complex environments remains a critical challenge. This research introduces an improved deep q-network algorithm for learning-based mobile robot navigation, addressing a multi-objective optimization problem that seeks to minimize path distance, energy consumption, and travel time within a grid-mapped complex environment. The deep q-network algorithm was enhanced to improve its efficiency in determining the optimal path to a target point. Experimental validation using a learning robot demonstrated the effectiveness of the proposed approach, ensuring safe path generation with collision avoidance, optimized path distance, and practical implementability in mobile robot applications. Furthermore, training, simulation, and analysis results revealed less than 2% deviations between simulation and experimental outcomes, with a path distance error of only 1.3765%. Finally, the proposed algorithm was benchmarked against existing approaches, including the A* algorithm, enhanced deep q-network, and dueling double deep q-network, showcasing its superior performance.
Robotics
Phongsavanh Sengaphone; Juan Miguel De Leon; Ronnie Concepcion; Argel A Bandala; Gerardo L Augusto; Raouf Naguib; Jeremias A Gonzaga; Joseph Aldrin Chua; Laurence A Gan Lim
Abstract
Integrating robotic technologies into agricultural practices has witnessed significant strides, particularly in tomato harvesting. This review paper offers a comprehensive examination of robot arms' end effectors developed for the intricate task of harvesting tomatoes. Drawing insights from a diverse ...
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Integrating robotic technologies into agricultural practices has witnessed significant strides, particularly in tomato harvesting. This review paper offers a comprehensive examination of robot arms' end effectors developed for the intricate task of harvesting tomatoes. Drawing insights from a diverse range of sources spanning Google Scholar, Scopus, IEEE Xplorer, and AnimoSearch, the study analyzes the trends, challenges, and future trajectories of employing robotic end effectors in the agricultural context. The investigation encompasses an in-depth exploration of various end-effector methodologies, including grippers, rotational mechanisms, scissor-type tools, and suction devices, elucidating their merits and prevalence in the current research literature. Focusing on the utilizations of end effectors in agricultural robotic harvesting systems, the review delves into fruit detachment methods, types of end tools designed explicitly for harvesting tomatoes, and the integration of sensors into end effectors for enhanced capabilities. The paper highlights the nuanced criteria involved in end effector design, emphasizing operational characteristics, technical features, and the need for adaptability to diverse fruit shapes. Furthermore, a detailed analysis of the challenges faced by end effectors in tomato harvesting is presented, with proposed solutions and recommendations for future research. The discussion extends to the future trends in this evolving field, envisioning advancements in sensing technology, artificial intelligence integration, adaptability, autonomy, and sustainability. In conclusion, the synthesis of technological innovation and agricultural expertise holds promise for reshaping tomato harvesting, paving the way for more sustainable, efficient, and cost-effective farming practices.
Robotics
M. Mohammadi; R. Dehghani; A. R. Ahmadi
Abstract
In this paper, a quadrotor with two manipulators constrained on a straight path is modeled and a robust adaptive controller is proposed for it. Adding two manipulators to quadrotor increases its capabilities and applications in industry. Here, these two manipulators are used to place the robot on a constraint ...
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In this paper, a quadrotor with two manipulators constrained on a straight path is modeled and a robust adaptive controller is proposed for it. Adding two manipulators to quadrotor increases its capabilities and applications in industry. Here, these two manipulators are used to place the robot on a constraint path so that the quadrotor can perform monitoring operations more accurately, since the under-actuated quadrotor becomes over-actuated by these constrained manipulators and one can use this feature to accurately control the position of the robot. Reduced form of motion equations is derived for the constrained quadrotor and based on this a robust adaptive controller is proposed. The nonlinear terms in the dynamic model are approximated by basic functions with constant weights; and adaptive laws are designed by projection operator. Stability analysis is performed based on the Lyapunov theory. Evaluation of the presented controller is done by some numerical simulations. The simulation results showed that the robot tracks the reference path with bounded error in spite of dynamic uncertainties and wind force; and satisfies the considered constraints.
Robotics
E. Neha; M. Suhaib; S. Asthana; S. Mukherjee
Abstract
The structure of the human hand is a complex design comprising of various bones, joints, tendons, and muscles functioning together in order to produce the desired motion. It becomes a challenging task to develop a robotic hand replicating the capabilities of the human hand. In this paper, the analysis ...
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The structure of the human hand is a complex design comprising of various bones, joints, tendons, and muscles functioning together in order to produce the desired motion. It becomes a challenging task to develop a robotic hand replicating the capabilities of the human hand. In this paper, the analysis of the four-fingered robotic hand is carried out where the tendon wires and a spring return mechanism is used for the flexion and extension motion of the fingers, respectively. Stable grasping and fine manipulation of different objects are desired from any multi-finger robotic hand. In this regard, it becomes necessary to check the performance of the four-fingered robotic hand. Simulations are performed for the hand to grasp objects of different size and shapes, and the hand model is controlled in a MATLAB environment using the SimMechanics toolbox. Here the Kinematics and Dynamics study of the hand system is carried out by importing the Solidworks model into the SimMechanics. Simulation results demonstrate that the developed hand model is able to grasp objects of varying size and shapes securely.
Robotics
Mohammad Hossein Falsafi; Khalil Alipour; Bahram Tarvirdizadeh
Abstract
Due to various advantages of Wheeled Mobile Robots (WMRs), many researchers have focused to solve their challenges. The automatic motion control of such robots is an attractive problem and is one of the issues which should carefully be examined. In the current paper, the trajectory tracking problem of ...
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Due to various advantages of Wheeled Mobile Robots (WMRs), many researchers have focused to solve their challenges. The automatic motion control of such robots is an attractive problem and is one of the issues which should carefully be examined. In the current paper, the trajectory tracking problem of WMRs which are actuated by two independent electrical motors is deliberated. To this end, and also, computer simulation of the system, first the system model is derived at the level of kinematics. The system model is nonholonomic. Then a simple non-mode-based controller based on fuzzy logic will be proposed. The control input resulted from fuzzy logic will then be corrected to fulfill the actuation saturation limits and non-slipping condition. To prove the efficiency of the suggested controller, its response, in terms of the required computational time burden and tracking error, will be compared with a previously suggested method. The obtained simulation results support the superiority of fuzzy based method over a previous study in terms of the considered measures.
Robotics
k. Alipour; m. Ghiasvand; B. Tarvirdizadeh
Abstract
In this paper, the important formation control problem of nonholonomic wheeled mobile robots is investigated via a leader-follower strategy. To this end, the dynamics model of the considered wheeled mobile robot is derived using Lagrange equations of motion. Then, using ADAMS multi-body simulation software, ...
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In this paper, the important formation control problem of nonholonomic wheeled mobile robots is investigated via a leader-follower strategy. To this end, the dynamics model of the considered wheeled mobile robot is derived using Lagrange equations of motion. Then, using ADAMS multi-body simulation software, the obtained dynamics of the wheeled system in MATLAB software is verified. After that, in order to generate and keep the desired formation, a Fuzzy Logic Controller is designed. In this regard, the leader mobile robot is controlled to follow a reference path and the follower robots use the Fuzzy Logic Controller to keep constant relative distance and constant angle with respect to the leader. The efficiency of the suggested dynamics-based formation controller has been proved using several computer simulations under different situations and desired trajectories. Also, the performance of the follower robot in path tracking is checked in the presence of receiving noisy data from the leader robot.
Robotics
M. H. Ghasemi; A. H. Korayem; S. R. Nekoo; M. H. Korayem
Abstract
Recording the variation of joint angles as a feedback to the control unit is frequent in articulated arms. In this paper, magnetic sensor AS5045, which is a contactless encoder, is employed to measure joint angles of 6R robot and the performance of that is examined. The sensor has a low volume, two digital ...
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Recording the variation of joint angles as a feedback to the control unit is frequent in articulated arms. In this paper, magnetic sensor AS5045, which is a contactless encoder, is employed to measure joint angles of 6R robot and the performance of that is examined. The sensor has a low volume, two digital outputs and provides a high resolution measurement for users; furthermore its zero position is adjustable. Installation and use of this measurement system on 6R robot has been expressed by using output signals of sensor AS5045 in the digital control board of 6R and equipped with ARM processor LPC1768. First, a sample of digital board is used for controlling a DC motor in both speed and position, in order to investigate specifications of AS5045’s digital and analogue outputs. Simulation of 6R robot in point-to-point motion has been performed with MATLAB software using a proportional derivative (PD) controller. Then, experiment with the same condition and gains via a PD controller has been designed and implemented on the digital control board. The feedback system has been also checked in a circular path to show its advantages in trajectory tracking. The comparison of simulation results with experiments shows improvement: less error and better performance of 6R robot. This new setup omitted the noise of previous analogue feedback system since its digital outputs provides a precise measurement.
Robotics
A. Rahmani Hanzaki; E. Yoosefi
Abstract
This paper shows the coordinates influence on singularity of a three degree-of-freedom structure, namely, three-Universal-Prismatic-Spherical (3-UPS) parallel manipulator. Rotational coordinates, which are chosen to define the orientation of the platform, affect the singularity of the manipulator. Euler ...
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This paper shows the coordinates influence on singularity of a three degree-of-freedom structure, namely, three-Universal-Prismatic-Spherical (3-UPS) parallel manipulator. Rotational coordinates, which are chosen to define the orientation of the platform, affect the singularity of the manipulator. Euler parameters, which don't have any inherent geometrical singularity are utilized, however they are dependent coordinates. This paper shows the advantage of Euler parameters rather than Euler angles as the rotational coordinates for the manipulator. Additionally, the real loci of singularity for the manipulator due to its structure are predicted.
