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Cable-based robots as well as their control are relatively new fields of research. The objective of this work is to design, simulate and compare two robot control techniques which are dedicated to be implemented for cable-based robots. The first controller is a classical proportional derivative one (PDC) while the second controller is the sliding mode one (SMC).

The proposed controllers are inserted into a closed loop around the cable-based robot for ensuring point to point transfer operations and trajectory tracking. Simulations have been carried out confirming the effectiveness of the PDC and SMC for controlling planar cable-based robots. Performances concerning settling time, precision, vibration and system stability are analyzed and compared. Some simulation results are presented showing, for each control techniques during trajectory tracking, the instantaneous profile evolution of cable lengths and cable tensions.

Cable-based Robots are new type of parallel robots that use cables instead of metallic cylinders. They have good properties that can be used for various applications. The main objective of this work is: the first is to use the direct and inverse geometric model to study and simulate the end effector position of the robot with three and four cables. A graphical user interface has been implemented in order to visualizing the position of the robot. Secondly, we present the determination of static and dynamic tensions and lengths of cables required to flow different trajectories. At the end, we study the response of our systems in closed loop with a Proportional-Integrated-Derivative (PID) and Proportional-Integrated (PD) controllers then this last are compared the results for the same examples using MATLAB/Simulink.; we found that the PID method gives the better performance, such as rapidly speed response, settling time, compared to PD controller.

This paper presents a modeling and control of new model in a spatial coordinates (x, y, z), from this structures we choose: regular pyramid of a square basis manipulated by five cables and eight cables for a cubic shape. The main objective of this work is to integrate the axe (z) on the horizontal plane (x, y) i-e the plan 3D. This last their intervention especially when we obliged to transfer the end effector from point to point, for that we used the direct and inverse geometric model to study and simulate the end effector position of the robot with five and eight cables. A graphical user interface has been implemented in order to visualizing the position of the robot. Secondly, we present the desired path and determination the tensions and cables lengths of kinematic model required to follow spiral trajectory. At the end, we study the response of our systems in closed loop with a Proportional-Integrated-Derivative (PID) using MATLAB/Simulink which used to verify the performance of the controller.

This paper presents the design and the implementation of a multimodal operator interface dedicated for planar cable-based robots. Three interactive robot control modes which have been implemented are namely point and click based control, gesture-based control and voice based control. Point and click based control enables robot control by simply clicking on features appearing on images of the robot workspace. Gestural-based control enables robot control by means of human operator gestures. Voice based control enables robot control by means of natural speech. Successful experiments have been tested on a homemade planar cable-driven robot. The availability and the combination of these three modes improve greatly the capability of the global system.

Pipeline robots are often used in pipeline non-destructive testing. Given the need for long-range in-pipe inspections, this study aims to develop a wireless in-pipe inspection robot for image acquisition.

In this paper, an in-pipe robot with a new mechanical system is proposed. This system combines a three-arm load-bearing structure with spring sleeves and a half-umbrella diametric change structure, which can ensure the stability of the camera when acquiring images while maintaining the robot’s flexibility. In addition, data were transmitted wirelessly via a system that uses a 433 MHz ultra-high frequency and wireless local-area network–based image transmission system. Software and practical tests were conducted to verify the robot’s design. A preliminary examination of the robot’s cruising range was also conducted.

The feasibility of the robot was demonstrated using CATIA V5 and MSC ADAMS software. The simulation results showed that the centre of mass of the robot remained in a stable position and that it could function in a simulated pipeline network. In the practical test, the prototype functioned stably, correctly executed remote instructions and transmitted in near real-time its location, battery voltage and the captured images. Additionally, the tests demonstrated that the robot could successfully pass through the bends in a 200-mm-wide pipe at any angle between 0° and 90°. In actual wireless network conditions, the electrical system functioned for 44.7 consecutive minutes.

A wheeled wireless robot adopts a new mechanical system. For inspections of plastic pipelines, the robot can adapt to pipes with diameters of 150–210 mm and has the potential for practical applications.

This paper aims to develop a robotic mirror therapy system for lower limb rehabilitation, which is applicable for different patients with individual movement disability levels.

This paper puts forward a novel system that includes a four-degree-of-freedom sitting/lying lower limb rehabilitation robot and a wireless motion data acquisition system based on mirror therapy principle. The magnetorheological (MR) actuators are designed and manufactured, whose characteristics are detected theoretically and experimentally. The passive training control strategy is proposed, and the trajectory tracking experiments verify its feasibility. Also, the active training controller that is adapt to the human motor ability is designed and evaluated by the comparison experiments.

The MR actuators produce continuously variable and compliant torque for robotic joints by adjusting excitation current. The reference limb joint position data collected by the wireless motion data acquisition system can be used as the motion trajectory of the robot to drive the affected limb. The passive training strategy based on proportional-integral control proves to have great trajectory tracking performance through experiments. In the active training mode, by comparing the real-time parameters adjustment in two phases, it is certified that the proposed fuzzy-based regulated impedance controller can adjust assistance torque according to the motor ability of the affected limb.

The system developed in this paper fulfills the needs of robot-assisted mirror therapy for hemiplegic patients.

The purpose of this paper is to study the preload range of tendon-driven manipulator and the relationship between preload and damping. The flexible joint manipulator (FJM) with joint flexibility is safer than traditional rigid manipulators. A FJM having an elastic tendon is called an elastic tendon-driven manipulator (ETDM) and has the advantages of being driven by a cable and having a more flexible joint. However, the elastic tendon introduces greater residual vibration, which makes the control of the manipulator more difficult. Accurate dynamic modeling is effective in solving this problem.

The present paper derives the relationship between the preload of the ETDM and the friction moment through the analysis of the forces of cables and pulleys. A dynamic model dominated by Coulomb damping is established.

The linear relationship between a decrease in the damping moment of the system and an increase in the ETDM preload is verified by mechanics analysis and experiment, and a curve of the relationship is obtained. This study provides a reference for the selection of ETDM preload.

The method to identify ETDM damping by vibration attenuation experiments is proposed, which is helpful to obtain a more accurate dynamic model of the system and to achieve accurate control and residual vibration suppression of ETDM.

Cables are widely used, and they play a key role in complex electromechanical products such as vehicles, ships, aircraft and satellites. Cable design and assembly significantly impact the development cycle and assembly quality, which is be-coming a key element affecting the function of a product. However, there are various kinds of cables, with complex geo-metric configurations and a narrow assembly space, which can easily result in improper or missed assembly, an unreasonable layout or interference. Traditional serial design methods are inefficient and costly, and they cannot predict problems in installation and use. Based on physical modeling, computer-aided cable design and assembly can effectively solve these problems. This paper aims to address virtual assembly (VA) of flexible cables based on physical modeling.

Much research has focused recently on virtual design and assembly-process planning for cables. This paper systematically reviews the research progress and the current state of mechanical models, virtual design, assembly-process planning, collision detection and geometric configuration and proposes areas for further research.

In the first instance, the main research groups and typical systems are investigated, followed by extensive exploration of the major research issues. The latter can be reviewed from five perspectives: the current state of mechanical models, virtual design, assembly-process planning, collision detection and geometric configuration. Finally, the barriers that prevent successful application of VA are also discussed, and the future research directions are summarized.

This paper presents a comprehensive survey of the topics of VA of flexible cables based on physical modeling and investigates some new ideas and recent advances in the area.

The purpose of this review paper is to address the substantial challenges of the outdated exoskeletons used for rehabilitation and further study the current advancements in this field. The shortcomings and technological developments in sensing the input signals to enable the desired motions, actuation, control and training methods are explained for further improvements in exoskeleton research.

Search platforms such as Web of Science, IEEE, Scopus and PubMed were used to collect the literature. The total number of recent articles referred to in this review paper with relevant keywords is filtered to 143.

Exoskeletons are getting smarter often with the integration of various modern tools to enhance the effectiveness of rehabilitation. The recent applications of bio signal sensing for rehabilitation to perform user-desired actions promote the development of independent exoskeleton systems. The modern concepts of artificial intelligence and machine learning enable the implementation of brain–computer interfacing (BCI) and hybrid BCIs in exoskeletons. Likewise, novel actuation techniques are necessary to overcome the significant challenges seen in conventional exoskeletons, such as the high-power requirements, poor back drivability, bulkiness and low energy efficiency. Implementation of suitable controller algorithms facilitates the instantaneous correction of actuation signals for all joints to obtain the desired motion. Furthermore, applying the traditional rehabilitation training methods is monotonous and exhausting for the user and the trainer. The incorporation of games, virtual reality (VR) and augmented reality (AR) technologies in exoskeletons has made rehabilitation training far more effective in recent times. The combination of electroencephalogram and electromyography-based hybrid BCI is desirable for signal sensing and controlling the exoskeletons based on user intentions. The challenges faced with actuation can be resolved by developing advanced power sources with minimal size and weight, easy portability, lower cost and good energy storage capacity. Implementation of novel smart materials enables a colossal scope for actuation in future exoskeleton developments. Improved versions of sliding mode control reported in the literature are suitable for robust control of nonlinear exoskeleton models. Optimizing the controller parameters with the help of evolutionary algorithms is also an effective method for exoskeleton control. The experiments using VR/AR and games for rehabilitation training yielded promising results as the performance of patients improved substantially.

Robotic exoskeleton-based rehabilitation will help to reduce the fatigue of physiotherapists. Repeated and intention-based exercise will improve the recovery of the affected part at a faster pace. Improved rehabilitation training methods like VR/AR-based technologies help in motivating the subject.

The paper describes the recent methods for signal sensing, actuation, control and rehabilitation training approaches used in developing exoskeletons. All these areas are key elements in an exoskeleton where the review papers are published very limitedly. Therefore, this paper will stand as a guide for the researchers working in this domain.