Pneumatic robotic arm controlled by on-off valves for automatic harvesting based on vision localisation

Recently, research and development has focused on robots that work in place of people. It is necessary for robots to perform the same flexible motions as people. Additionally, such robots need to incorporate high-level safety features in order not to injure people. For creation of such robots, we need to develop a robot hand that functions like a human hand. At the same time, this type of robot hand can be used as an artificial hand. Here, we present artificial muscle-type pneumatic actuators as the driving source of a robot hand that is both safe and flexible. Some development of robot hands using pneumatic actuators has already taken place. However, until now, when a pneumatic actuator is used, a big compressor is needed. Therefore, the driving system also needs to be big, and enlargement of the driving system is a major problem. Consequently, in this research, we develop a low-pressure, low-volume pneumatic actuator for driving a robot hand that works flexibly and safely on the assumption that it will be in contact with people. We develop a five-fingered robot hand with pneumatic actuators. Next, we make a 1-link arm that has one degree of freedom using a pneumatic actuator, and models of the actuator and 1-link arm are constructed. A control PID control system is constructed, and the gains of the PID control system are determined by the simulation that uses the model of the 1-link arm. The step response of the joint angle is examined with the determined gains, and control performance of the PID control system is verified.

Since robotic arms operating close to people are becoming increasingly common, there is a need to better understand how they can be made safe when unintended contact occurs, while still providing the required performance. Several actuators and methods for improving robot safety are studied and compared in this paper. A robotic arm moving its end effector horizontally and colliding with a person’s head is simulated. The use of a conventional electric actuator (CEA), series elastic actuator (SEA), pneumatic actuator (PA) and hybrid pneumatic electric actuator (HPEA) with model-based controllers are studied. The addition of a compliant covering to the arm and the use of collision detection and reaction strategies are also studied. The simulations include sensor noise and modeling error to improve their realism. A systematic method for tuning the controllers fairly is proposed. The motion control performance and safety of the robot are quantified using root mean square error (RMSE) between the desired and actual joint angle trajectories and maximum impact force (MIF), respectively. The results show that the RMSE values are similar when the CEA, SEA, and HPEA drive the robot’s first joint. Regarding safety, using the PA or HPEA with a compliant covering can reduce the MIF below the safety limit established by the International Organization for Standardization (ISO). To satisfy this ISO safety limit with the CEA and SEA, a collision detection and reaction strategy must be used in addition to the compliant covering. The influences of the compliant covering’s stiffness and the detection delay are also studied.

In this paper, an interactive robotic anthropomorphic hand system is presented, which was developed as an important tool for the educational outreach activities. The robotic anthropomorphic hand incorporates 15 degrees of freedom, providing sufficient mobility in the demonstration of various postures. To increase the attractiveness of the robotic hand, pneumatic muscle actuators are used to drive the robotic hand motion through artificial tendons. The interaction of the robotic hand with a human is enabled with a control device, which allows the human operator to control the hand motion in a natural way. The robotic hand system has been successfully demonstrated in a recent engineering education outreach event, in which over 100 children at all ages operated the robotic hand through the control device.

Recently, research has focused on pneumatic robot. Here, we present artificial muscle-type pneumatic actuators as the driving source of a robot hand that is both safe and flexible. We develop a five-fingered robot hand with pneumatic actuators of low-pressure and low-volume. To control this hand in high accuracy, we construct the spring-damper model of the pneumatic actuator. We produce a I-link arm. We construct the model of 1-link arm that considers moment of inertia and the viscous friction coefficient. We construct a control system for 1-link arm. In addition, the effectiveness of the constructed model is verified by the experiment.

Practical and intuitive controller design method for precision positioning of a pneumatic cylinder actuator stage

The purpose of this study is a development of a nonmetallic and light robot hand driven by low-pressure pneumatic actuators. As the robot hand is used pneumatic actuators, if a human touches the robot hand, it is safe. The results of characteristics of the pneumatic actuator proved that it is possible to drive the robot hand and get enough generated force to grasp objects by lower inner pressure and lower air volume. Therefore, a model the same size as a human hand can be made without a big air compressor, and applications for prosthetic hands are considered.

Based on aging Japanese society, there has been a strong desire for development of rehabilitation devices that patients can use at home. The purpose of this study is to develop a home-based compact, lightweight, flexible, and safe rehabilitation device. In this study, a flexible robot arm for wrist rehabilitation that can be used, while patients hold the top of the robot arm, is proposed and tested. The proposed robot arm consists of three extension type flexible pneumatic actuators (EFPAs) restrained by 22 PET sheets. To achieve suitable bending stiffness of the robot arm, three EFPAs are restrained so as to form a tetrahedral shape. The robot arm can bend toward each radial direction. In this paper, the construction and operational principles of the tested robot arm are described. Additionally, the analytical model of the robot arm for attitude control is also described. In addition, the tracking control using the robot arm for the desired orbit is performed. As a result, the tested robot arm can trace the desired orbit based on the model. It is confirmed that the robot arm has the possibility for application as a wrist rehabilitation device for patients.

This paper presents the detailed analysis of a pneumatic clutch actuator with an artificial intelligence control algorithm. The low cost of pneumatic actuator makes it an advantage in automotive applications, but fast and precise control is difficult on account of its time-varying and nonlinear character. In order to achieve good performance and save cost, the development of a fast, accurate, and inexpensive automatic pneumatic actuator clutch system for a single-axle parallel hybrid electrical is important. Targeted for the working principle of electric-drive automated mechanical transmission parallel hybrid system for shifting and clutch dynamic control during operation mode switch course, the design adopts single neuron-adaptive PID-based clutch operation process, proposed the clutch actuator piston non-contact cylinder lock control method to overcome time-varying and nonlinear characteristics’ impact present in the pneumatic actuator closed-loop control, and through the effective control of segment displacement self-diagnosis during the clutch operation process, performs variable clutch control and improve the actuator fault tolerance. Experiments show that the proposed control algorithm is feasible, which has effectively reduced the torque shock and clutch friction work during clutch engaging process.

<p>A pneumatic actuator is a device that converts compressed air into mechanical energy to perform varieties of work. It exhibits high nonlinearities due to high friction forces, compressibility of air and dead band of the spool movement which is difficult to manage and requires an appropriate controller for better performance. The purpose of this study is to review the controller design of pneumatic actuator recommended by previous researchers from the past years. Initially, the basic views of the pneumatic will be presented in terms of introduction to the pneumatic actuator and its applications in industries. At the end of this review, discussions on the design of the controllers will be concluded and further research will be proposed along with the improvement of control strategies in the pneumatic actuator systems</p>

In this paper, a fabric-based wearable soft robotic limb (SRL) is presented. It can be worn on the user’s body to potentially assist with activities of daily living. This SRL can perform a bidirectional bending motion by inflating the pneumatic bending actuators. The end effector, which is a fabric-based soft gripper, can pick up small objects in daily life. The SRL is pneumatically actuated, and its bending motion and payload capability were characterized. All the actuation and control systems are integrated in a portable control box. The SRL can be voice-controlled using an Android-based voice recognition mobile application. We expect the SRL to be a promising wearable tool that can assist the user in managing simple activities in daily living, while allowing the user’s natural human hands to work on more complex tasks.

Pneumatic soft robotic systems show remarkable potentials in producing versatile locomotion and manipulations, owing to their flexibility in structural design and material selections. However, fabrication of pneumatic soft robotic systems with complex 3D structures and material distribution still remains elusive. Herein, a mode‐free fabrication approach, called planar laser cutting and stacking fabrication (PLCSF), is proposed to create pneumatic soft robotic systems with multi‐material and complex structure, which involves the following steps: 1) slicing the 3D model of desired pneumatic soft robotic systems into 2D layers; 2) fabricating each layer via laser cutting corresponding 2D membrane; 3) stacking all layers together to finish the fabrication. With the PLCSF approach, various prevalent pneumatic soft actuators are fabricated with complex structures (including fiber‐reinforced and pneu‐net) and different actuation modes (such as bending, elongation, twisting, abduction, contraction, and grabbing). The scalability of the PLCSF approach to fabricate multiple degrees‐of‐freedom (DOFs) pneumatic soft actuators with integrated structures, such as twisting‐bending pneumatic soft actuators for delivering and bending‐elongation‐bending pneumatic soft actuators for crawling, is also demonstrated. It is further demonstrated that the PLCSF approach also enables creating a bio‐inspired soft hand with nine DOFs, capable of various dexterous motions and manipulations.

This paper presents a simple approach to mimic human motion. The objective of this research is to mimic the human motions using visual feedback and convert it into robotic motion. A 3 degree-of-freedom robotic arm is developed that utilizes visual feedback capturing the human hand motion. The motion of the robotic arm is governed by converting the workspace configuration into configuration space using inverse kinematics. The proposed approach is applied to freehand drawing and is implemented in real-time. The real-time human hand following robot arm shows that it can be used for environments endangered for humans effectively.

In this study, we propose a novel micro valve usingPluronic^[○!R] F127 as thermally responsive solution. It was hard to integrated conventional micro valves into micro devices because of their complicated composition. Thus, we propose novel micro valve to be integrated with pneumatic micro actuator. The thermally responsive solution valve was designed and fabricated by using micro channel containing thermally responsive solution with micro heater. The micro valve can be reversibly driven by heating and gellirig of thermally responsive solution. Furthermore,we integrated the micro valve topneumatic balloon actuator and successfully controlled its actuation by developed micro valve. Integration of a valve into pneumatic actuator allows designing compact pneumatic actuator system.

A speed controller's primary input, for an internal combustion engine-based vehicle, is the throttle angle. The most common way to adjust the throttle angle setting is with a pneumatic actuator. When a faster and more accurate throttle response is desired, the pneumatic based system is generally replaced with a stepping motor mounted directly on the throttle plate assembly. For controller design purposes that fit the physical situation, a model of the throttle actuator system has been developed that is comprised of two second-order linear systems. Using this variable structure model, a switching controller has been designed which has been verified, both theoretically and experimentally, to work satisfactorily. This paper provides an interesting example of designing a reference tracking controller for a real physical system by switching between its stable and unstable structures while achieving closed loop stability.

Nowadays, the robotic arm is fast becoming the most popular robotic form used in the industry among others. Therefore, the issues regarding remote monitoring and controlling system are very important, which measures different environmental parameters at a distance away from the room and sets various condition for a desired environment through a wireless communication system operated from a central room. Thus, it is crucial to create a programming system which can control the movement of each part of the industrial robot in order to ensure it functions properly. EDARM ED-7100 is one of the simplest models of the robotic arm, which has a manual controller to control the movement of the robotic arm. In order to improve this control system, a new controller system was redesigned in this work by using Zigbee. It is a communication protocol for safety and economic data communication in an industrial field, where the wired communication is either expensive or difficult under physical and experimental conditions, such as the worker cannot recognize the error through the manufacturing process. Hence, this paper introduced a system that used microcontroller (AT89S52) with wireless devices (Zigbee) and sensors to control the robotic hand (EDARM ED-7100) and to monitor the information regarding the robot's parameter using WiFi technology. A mathematical model was derived through an empirical method to specify the robot's configuration changes. In this work, the ability of controlling system had increased, as well as hardware, while the necessities of other similar equipment for data communication were minimized. In addition, it presents the comparison of two controlling systems: using the Zigbee and without using it. Based from the experiment it can be safely concluded that the robotic arm's movement had followed a linear function.