scholarly journals Conceptual Design of a High-Speed Wire EDM Robotic End-Effector Based on a Systematic Review Followed by TRIZ

Machines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 132
Author(s):  
Sergio Tadeu Almeida ◽  
John Mo ◽  
Cees Bil ◽  
Songlin Ding ◽  
Xiangzhi Wang
Keyword(s):  
High Speed ◽  
Dimensional Accuracy ◽  
Research Field ◽  
Industrial Robots ◽  
Cnc Machining ◽  
Surface Finishing ◽  
Robot Arm ◽  
Technical Problems ◽  
End Effector ◽  
Robotic Machining

Exotic materials such as titanium offer superior characteristics that, paradoxically, make them hard-to-cut by conventional machining. As a solution, electric discharge machining (EDM) stands out as a non-conventional process able to cut complex profiles from hard-to-cut materials, delivering dimensional accuracy and a superior surface. However, EDM is embodied in CNC machines with a reduced axis and machining envelope, which constrains design freedom in terms of size and shape. To overcome these CNC constraints, traditional machining using six-axis industrial robots have become a prominent research field, and some applications have achieved cost efficiency, an improved envelope, and high flexibility. However, due to the lack of stiffness and strength of the robot arm, accuracy, material rate removal, and surface finishing are not comparable to CNC machining. Therefore, the present study investigates the design of a novel WEDM combined with six-axis robotic machining to overcome the limitations of traditional robotic machining and enhance EDM applications. This study extends the work of a conference paper to confirm potential outcomes, quantifying and ranking undesired interactions to map technical problems and applying the TRIZ approach to trigger solutions. Finally, an effective robotic end-effector design is proposed to free EDM from CNC and deliver robotic machining as a flexible and accurate machining system for exotic materials.

scholarly journals Detachable Robotic Grippers for Human-Robot Collaboration

2021 ◽  
Vol 8 ◽  
Author(s):  
Zubair Iqbal ◽  
Maria Pozzi ◽  
Domenico Prattichizzo ◽  
Gionata Salvietti
Keyword(s):  
Degrees Of Freedom ◽  
Tactile Feedback ◽  
Industrial Robots ◽  
Physical Interaction ◽  
Robot Arm ◽  
Robotic Hands ◽  
End Effector ◽  
External Power ◽  
Self Powered ◽  
Automatic Tool

Collaborative robots promise to add flexibility to production cells thanks to the fact that they can work not only close to humans but also with humans. The possibility of a direct physical interaction between humans and robots allows to perform operations that were inconceivable with industrial robots. Collaborative soft grippers have been recently introduced to extend this possibility beyond the robot end-effector, making humans able to directly act on robotic hands. In this work, we propose to exploit collaborative grippers in a novel paradigm in which these devices can be easily attached and detached from the robot arm and used also independently from it. This is possible only with self-powered hands, that are still quite uncommon in the market. In the presented paradigm not only hands can be attached/detached to/from the robot end-effector as if they were simple tools, but they can also remain active and fully functional after detachment. This ensures all the advantages brought in by tool changers, that allow for quick and possibly automatic tool exchange at the robot end-effector, but also gives the possibility of using the hand capabilities and degrees of freedom without the need of an arm or of external power supplies. In this paper, the concept of detachable robotic grippers is introduced and demonstrated through two illustrative tasks conducted with a new tool changer designed for collaborative grippers. The novel tool changer embeds electromagnets that are used to add safety during attach/detach operations. The activation of the electromagnets is controlled through a wearable interface capable of providing tactile feedback. The usability of the system is confirmed by the evaluations of 12 users.

scholarly journals Robotic Surface Finishing of Curved Surfaces: Real-Time Identification of Surface Profile and Control

2018 ◽  
Author(s):  
Yalun Wen ◽  
Prabhakar R. Pagilla
Keyword(s):  
Real Time ◽  
Force Control ◽  
Surface Profile ◽  
Industrial Robots ◽  
Surface Finishing ◽  
Laser Sensor ◽  
Curved Surfaces ◽  
End Effector ◽  
Real Time Identification ◽  
Finishing Tool

An efficient strategy for robotic surface finishing of curved surfaces that includes real-time identification of the surface profile, control, and implementation is presented in this paper. Real-time identification of the surface profile in the robot base frame is accomplished by employing a proximity laser sensor mounted on the robot end-effector. This surface profile description allows us to generate trajectories for both motion and force control as it provides the surface normal at each point of the surface. Using the surface profile, a trajectory is generated that would orient the surface finishing tool to the local normal of the surface. An algorithm for simultaneous position and force control is developed for surface finishing of curved surfaces. The integrated robotic surface finishing system consists of a UR5 robot and a custom end-effector that includes a force/torque sensor, an electromechanical sander, and the proximity laser sensor. Robot Operating System (ROS) is utilized for real-time implementation, which would enable easy migration of the developed tools if other industrial robots are used. The effectiveness of the strategy is evaluated by conducting a number of experiments for flat and curved surfaces. A representative sample of results on force regulation and surface finishing are presented and discussed.

scholarly journals Analysis of the Compliance Properties of an Industrial Robot with the Mozzi Axis Approach

Robotics ◽  
2019 ◽  
Vol 8 (3) ◽  
pp. 80 ◽  
Author(s):  
Doria ◽  
Cocuzza ◽  
Comand ◽  
Bottin ◽  
Rossi
Keyword(s):  
Industrial Robot ◽  
Industrial Robots ◽  
Robotic Assembly ◽  
Robot Arm ◽  
Machined Surface ◽  
End Effector ◽  
Chatter Vibrations ◽  
Modes Of Vibration ◽  
Machining Robot ◽  
Robot Performance

In robotic processes, the compliance of the robot arm plays a very important role. In some conditions, for example, in robotic assembly, robot arm compliance can compensate for small position and orientation errors of the end-effector. In other processes, like machining, robot compliance may generate chatter vibrations with an impairment in the quality of the machined surface. In industrial robots, the compliance of the end-effector is chiefly due to joint compliances. In this paper, joint compliances of a serial six-joint industrial robot are identified with a novel modal method making use of specific modes of vibration dominated by the compliance of only one joint. Then, in order to represent the effect of the identified compliances on robot performance in an intuitive and geometric way, a novel kinematic method based on the concept of “Mozzi axis” of the end-effector is presented and discussed.

Research on Hydraulic System of Speed Forging Hydraulic Machine

2012 ◽  
Vol 192 ◽  
pp. 123-127 ◽  
Author(s):  
Hao Yang Yu ◽  
Jing Lin Tang ◽  
Jing Hu
Keyword(s):  
Hydraulic System ◽  
High Speed ◽  
Computer Network ◽  
Dimensional Accuracy ◽  
Modern Society ◽  
Industrial Robots ◽  
Large Set ◽  
Hydraulic Machine ◽  
Automated Warehouses ◽  
Important Position

In recent years, industrial technology in China continues developing fast, and this has put forward higher requirements for China's forging equipment. The development international direction of the forging equipment is multi-bit, high-speed and large-set, which leads to the combination of a number of technologies such as hydraulic, pneumatic, electronic, mechanization and detection. However, China's forging press is still at a relatively low level. The organically combination of CNC system with the computer, network, automated warehouses, automatic mold change systems and industrial robots has made the development of the manufacture more and more intelligent as well as its technology level more and more intelligent. In order to occupy a place in the international arena, it is imminent to vigorously develop China's forging equipment. As high speed forging hydraulic machine occupies a very important position in the whole forging system, and the requirement on the dimensional accuracy and productivity of industrial products is getting higher and higher in modern society. This paper introduces the analysis and researches on the hydraulic system of high speed forging hydraulic machine, which is also the difficult and hot point of social researches.

scholarly journals A Robotic System to Scan and Reproduce Object

2011 ◽  
Vol 2011 ◽  
pp. 1-11
Author(s):  
Cesare Rossi ◽  
Sergio Savino
Keyword(s):  
High Speed ◽  
Mechanical Engineering ◽  
Vision System ◽  
Laser Scanner ◽  
Robotic System ◽  
Robot Arm ◽  
End Effector ◽  
Laser Projector ◽  
Cloud Of Points ◽  
Linear Laser

An application of a robotic system integrated with a vision system is presented. The robot is a 3-axis revolute prototype, while the vision system essentially consists in a laser scanner made up of a camera and a linear laser projector. Both the robotic and the video system were designed and built at DIME (Department of Mechanical Engineering for Energetics), University of Naples Federico II. The presented application essentially consists of a laser scanner that is installed on the robot arm; the scanner scans a 3D surface, and the data are converted in a cloud of points in the robot’s workspace. Then, starting from those points, the end-effector trajectories adopted to replicate the scanned surface are calculated; so, the same robot, by using a tool, can reproduce the scanned object. The software was developed also at the DIME. The adopted tool was a high-speed drill, installed on the last link of the robot arm, with a spherical milling cutter in order to obtain enough accurate surfaces by the data represented by the cloud of points. An algorithm to interpolate the paths and to plan the trajectories was also developed and successfully tested.

scholarly journals Study on image processing method to classify objects on dynamic conveyor

2020 ◽  
Vol 2 (SI2) ◽  
pp. First
Author(s):  
Huy Ngoc Tran
Keyword(s):  
Image Processing ◽  
High Speed ◽  
Object Identification ◽  
Industrial Robots ◽  
Robotic Arm ◽  
Robot Arm ◽  
Vision Sensor ◽  
Image Processing Algorithm ◽  
Product Packaging ◽  
Object A

Controlling a robotic arms for applications such as detection and classification moving object using the vision sensor is a trend in the field of industrial robots. In particular, the vision sensor is the "eye" of the robot. To solve this problem, we need an efficient image processing algorithm for object identification to optimize the speed. Our classification principle based on the color of the object to be classified first, then separating contour to classify according to the shape of the object. In addition, our paper also propose a classification method that rarely mentioned in the relevant documents that classify based on object's characteristic. In fact, the product packaging not only has one color, but also includes complex color and patterns. Being able to classify these products shows the practicality of the proposed method. For complex colors and patterns object, the PCASIFT algorithm is useful, where SIFT extracts the local characteristics of the object and PCA reduces the number of dimensionality and retain only the best characteristics for identification. To picking object, a proposed design with the optimal requirements of picking order so that picking time is the shortest to minimize the delay for the next picking. The other outstanding advantage is a system of robotic arm to perform pick-up and sorting. This helps to verify good running algorithms in real time. The items are randomly released and the rotation of items is random. The speed of the conveyor is 5cm/s, an average of more than 2 seconds to pick up an object and robot arm processing precisely at high speed. The experimental results using camera Logitech C270, Yamaha Scara YK-400X robotic arm, LabVolt conveyor and OpenCV library are satisfactory, reliable and applicable.

Improving surface quality of selective laser sintered rapid prototype parts using robotic finishing

2000 ◽  
Vol 214 (3) ◽  
pp. 197-203 ◽  
Author(s):  
D Shi ◽  
I Gibson
Keyword(s):  
Surface Quality ◽  
Computer Aided Design ◽  
High Speed ◽  
Selective Laser Sintering ◽  
Rapid Prototype ◽  
Dimensional Accuracy ◽  
Surface Finishing ◽  
Calibration Data ◽  
Computer Aided ◽  
Finishing Tool

Because of ‘stair-step’ and ‘shrinkage’ effects, most rapid prototyping (RP) parts have need of surface finishing in post-processing to obtain good surface quality. Instead of manual operations or homogeneous polishing techniques, a robot, with its high flexibility and sophistication, can effectively finish the surfaces of selective laser sintering (SLS) parts. After the sintering process, an SLS part that requires finishing is placed on a fixture with the help of a special base fitting. By calibrating the base fitting, the position and orientation of the part relative to the robotic system are determined. The robot holds a finishing tool, which can be changed according to different materials and different surfaces, as its end-effector. Once the calibration data, finishing tool, surfaces to be finished and finishing parameters are determined, the robotic finishing path can be automatically programmed from the computer aided design/computer aided modelling (CAD/CAM) model. The robot then moves a high-speed finishing tool over the desired surfaces according to the finishing path. Some experiments have been carried out on different SLS parts using different materials. It is shown that surface quality, which includes surface roughness, dimensional accuracy as well as geometrical accuracy, can be improved using robotic finishing.

scholarly journals Experimental studies of robotic assembly of precision parts

2021 ◽  
Vol 49 (1) ◽  
pp. 44-55
Author(s):  
Mikhail Polishchuk ◽  
M. Tkach
Keyword(s):  
High Speed ◽  
Industrial Robot ◽  
Economic Effect ◽  
Experimental Studies ◽  
Industrial Robots ◽  
Robotic Assembly ◽  
Robot Arm ◽  
Positioning Accuracy ◽  
Position Correction ◽  
The Cost

At present, robotization of assembly processes is achieved through the use of industrial robots with high positioning accuracy in conjunction with tactile means of adaptation to the conditions of assembly of precision parts. The cost of such robots is many times higher than the cost of simple robots with low positioning accuracy of the robot arm. The research in this article is aimed at reducing the cost of assembly processes for precision parts by applying the position correction of the connected parts not by the robot hand, but by an additional technological module that is installed on the manipulator of a simple robot and performs high-speed stochastic mismatch scan of assembly objects. The article presents the results of a full factorial experiment of the process of joining precision cylindrical parts with a gap of no more than 3...5 microns. A regression model of this process is proposed, a formula for calculating the quasi-optimal modes of precision assembly and graphanalytical dependences of the assembly time on the scanning modes of the misalignment of assembly objects are given. The proposed high-speed method for compensating for the positioning error of an industrial robot makes it possible to assemble precision parts in a very short time within 1...3(s). The main economic effect of the research results is that the device for scanning the misalignment of assembly objects, which is installed on the arm of an inexpensive robot with a low positioning accuracy, can significantly increase the assembly speed and reduce capital investments in robotic assembly of high-precision parts.

Review of Research on Hydrostatic Bearings

2020 ◽  
Vol 13 ◽  
Author(s):  
Xiaodong Yu ◽  
Yu Wang ◽  
Junfeng Wang ◽  
Wenkai Zhou ◽  
Hongwei Bi ◽  
...  
Keyword(s):  
High Speed ◽  
Static Pressure ◽  
Development Trend ◽  
Cnc Machining ◽  
Pressure Effects ◽  
Cnc Machine Tools ◽  
Future Research ◽  
Theoretical Formula ◽  
Hydrostatic Bearing ◽  
Hydrostatic Bearings

Background: Hydrostatic bearings have the advantages of strong bearing capacity, good stability, small friction coefficient and long life. The performance of liquid hydrostatic bearings directly affect the accuracy and efficiency of CNC machining equipment. The performance is conducive to the development of CNC machine tools towards high speed and heavy load, so it is necessary to sort out and summarize the existing research results. Objective: This study summarizes the current development status of hydrostatic bearings and explains the development trend of hydrostatic bearings. Methods: According to the recently published journal articles and patents, the recent experimental research on hydrostatic thrust bearings is summarized. This paper summarizes many factors that affect the performance of hydrostatic bearings, and discusses the causes of various factors on hydrostatic bearings. Finally, future research on hydrostatic bearings is presented. Results: The study discusses experimental methods, simulation processes, and experimental results. Conclusion: This study can produce dynamic and static pressure effects by changing the structure of the oil cavity of the hydrostatic bearing. This effect can make up for the static pressure loss. By improving the theoretical formula and mathematical model and proposing a new simulation method, the accuracy of the hydrostatic bearing simulation is satisfied; the future development trend of the hydrostatic bearing is proposed.

Three-Degree-of-Freedom Parallel Robot Arm

2006 ◽  
Author(s):  
Martin Hosek ◽  
Michael Valasek ◽  
Jairo Moura
Keyword(s):  
Parallel Robot ◽  
Degree Of Freedom ◽  
Motion Path ◽  
Angular Orientation ◽  
Robot Arm ◽  
Flat Panel Display ◽  
End Effector ◽  
Cluster Tools ◽  
Manufacturing Applications ◽  
Three Degree Of Freedom

This paper presents single- and dual-end-effector configurations of a planar three-degree of freedom parallel robot arm designed for automated pick-place operations in vacuum cluster tools for semiconductor and flat-panel-display manufacturing applications. The basic single end-effector configuration of the arm consists of a pivoting base platform, two elbow platforms and a wrist platform, which are connected through two symmetric pairs of parallelogram mechanisms. The wrist platform carries an end-effector, the position and angular orientation of which can be controlled independently by three motors located at the base of the robot. The joints and links of the mechanism are arranged in a unique geometric configuration which provides a sufficient range of motion for typical vacuum cluster tools. The geometric properties of the mechanism are further optimized for a given motion path of the robot. In addition to the basic symmetric single end-effector configuration, an asymmetric costeffective version of the mechanism is derived, and two dual-end-effector alternatives for improved throughput performance are described. In contrast to prior attempts to control angular orientation of the end-effector(s) of the conventional arms employed currently in vacuum cluster tools, all of the motors that drive the arm can be located at the stationary base of the robot with no need for joint actuators carried by the arm or complicated belt arrangements running through the arm. As a result, the motors do not contribute to the mass and inertia properties of the moving parts of the arm, no power and signal wires through the arm are necessary, the reliability and maintenance aspects of operation are improved, and the level of undesirable particle generation is reduced. This is particularly beneficial for high-throughput applications in vacuum and particlesensitive environments.

Sign in / Sign up

Export Citation Format

Share Document