Planning of Robotic Inspection from Visual Tracking of Manual Surface Finishing Tool

Abstract In this paper, AlSi10Mg alloy powder is selected as the forming powder of Selective Laser Melting technology, and the AlSi10Mg alloy SLM curved surface sample is constructed by setting the internal and external layering parameters. In view of the relatively rough surface roughness of SLM technology molded parts, this paper selects the magnetic finishing technology with higher flexibility characteristics to perform surface finishing and finishing on the formed curved surface samples. Explore the feasibility of magnetic finishing technology on the finishing of SLM shaped curved parts, and test and analyze the surface roughness, surface hardness and hydrophobicity of the finishing permanent magnet tools and the curved surface samples before and after finishing. Finally, it was found that the use of a 75° trapezoidal slotted permanent magnet finishing tool to absorb spherical Al2O3 magnetic abrasives for flexible finishing of AlSi10Mg alloy SLM shaped curved surface samples can achieve better finishing results.In this paper, the orthogonal experiment method is used to optimize the finishing experiment. It is found that the finishing parameters of the spindle speed is 1800 r/min, the feed rate is 5 mm/min, the gap is 2 mm, and the abrasive consumption is 7g to form the AlSi10Mg alloy SLM. The surface roughness Ra=0.279μm can be obtained by magnetic finishing of the curved sample, and the surface morphology of the sample has been greatly improved. At the same time, it is found that the magnetic finishing technology improves the surface roughness of the AlSi10Mg alloy SLM forming surface sample, while it does not change the surface hardness of the sample, but it can significantly improve the hydrophobicity of the sample surface.

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

Volume 3: Manufacturing Equipment and Systems ◽

10.1115/msec2018-6659 ◽

2018 ◽

Cited By ~ 3

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.

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Machine Vision Monitoring for Automated Surface Finishing

Journal of Manufacturing Science and Engineering ◽

10.1115/1.2832703 ◽

1999 ◽

Vol 121 (3) ◽

pp. 457-465 ◽

Cited By ~ 3

Author(s):

C. Bradley ◽

S. Kurada

Keyword(s):

Surface Roughness ◽

Machine Vision ◽

Closed Loop ◽

Surface Finishing ◽

Critical Surface ◽

Closed Loop System ◽

Texture Information ◽

Computer Controlled ◽

Finishing Tool ◽

Die And Mold

A considerable amount of research has recently been performed on automated die and mold finishing systems. The research has tended to focus on the development of the finishing tool, the means of positioning and controlling the tool or efficient algorithms for moving the tool to achieve desired degrees of surface roughness. However, there has been relatively less effort to develop sensors suitable for providing the critical surface finish data necessary for any closed loop system. This paper presents two algorithms that, when coupled with machine vision hardware, are capable of providing surface texture information. The algorithms are developed and the results calibrated against a stylus profilometer. Tests have been conducted on mold cavity surfaces and the results evaluated against standard tactile means. The hardware has been incorporated with a computer controlled coordinate machine.

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Grinding Finishing Merging Electropolishing on Hole-Wall Surfaces

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.4071 ◽

2010 ◽

Vol 97-101 ◽

pp. 4071-4074

Author(s):

Pai Shan Pa

Keyword(s):

Machining Process ◽

Surface Finishing ◽

Grinding Wheel ◽

Wall Surface ◽

Processing Parameter ◽

Complete Evaluation ◽

Hole Wall ◽

Finishing Process ◽

Electrochemical Finishing ◽

Finishing Tool

The current study presents a method for finishing hole-wall surfaces, superior to that obtainable by traditional boring, using a simultaneous grinding and electropolishing process. A specially designed finishing tool, that includes a nonconductive grinding wheel and an electrode is employed in the process. The form of the tool and the machining process are different from those used in electrochemical grinding (ECG). A high power electrical supply is not required with this design of finishing tool because the axial feed allows for the use of a smaller interactive area between the electrode and the hole wall surface. The experimental results show that a high current flow combined with a fast axial feed rate for the tool is an important advantage to the finishing process. The finishing effect is better with high rotational tool speeds because discharge of the electropolishing dregs and grinding cuttings becomes more efficient and this is also advantageous to the grinding finishing process. Pulsed direct current can slightly improve the electrochemical finishing effect, but machining takes longer and this raises costs. A small edge radius on the electrode also provides more than sufficient discharge and gives a better finish. We intend to make a complete evaluation of the processing parameter data so that the use of this method for hole-wall surface finishing may be extended in the future. The combined application of grinding and electropolishing is crucial to this method and the specially designed tool and the new finishing process are highly efficient and inexpensive.

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

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1243/0954405001517586 ◽

2000 ◽

Vol 214 (3) ◽

pp. 197-203 ◽

Cited By ~ 17

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.

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View Planning for Robotic Inspection of Tolerances Through Visual Tracking of Manual Surface Finishing Operations

International Journal of Robotic Computing ◽

10.35708/rc1869-126261 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Eirik B. Njaastad

Keyword(s):

Visual Tracking ◽

Tracking System ◽

Low Cost ◽

Principal Component ◽

Surface Finishing ◽

Skilled Worker ◽

View Planning ◽

Tool Paths ◽

Camera View ◽

Ship Propeller

This article presents an approach for determining suitable camera view poses for inspection of surface tolerances based on visual tracking of the tool movements performed by a skilled worker. Automated surface inspection of a workpiece adjusted by manual operations depends on manual programming of the inspecting robot, or a timeconsuming exhaustive search over the entire surface. The proposed approach is based on the assumption that the tool movements of the skilled worker coincide with the most relevant regions of the underlying surface of the workpiece, namely the parts where a manual process has been performed. The affected region is detected with a visual tracking system, which measures the motion of the tool using a low-cost RGBD-camera, a particle filter, and a CAD model of the tool. The main contribution is a scheme for selecting relevant camera view poses for inspecting the affected region using a robot equipped with a high-accuracy RGBDcamera. A principal component analysis of the tracked tool paths allows for evaluating the view poses by the Hotelling’s T-squared distribution test in order to sort and select suitable camera view poses. The approach is implemented and tested for the case where a large ship propeller blade cast in NiAl bronze is to be inspected by a robot after manual adjustments of its surface.

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