Precision Robotic Milling of Fiberglass Shims in Aircraft Wing
                    Assembly Using Laser Tracker Feedback

Nguyen, Vinh; Cvitanic, Toni; Baxter, Matthew; Ahlin, Konrad; Johnson, Joshua; Freeman, Philip; Balakirsky, Stephen; Brown, Allison; Melkote, Shreyes N.

doi:10.4271/01-15-01-0006

Cited by 3 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The first laser tracker system was invented in the 1980s to perform critical and highly accurate position measurements [7]. To date, this system is used to perform dimension measurements on large-scale aircraft workpieces [8,9], astronomical telescopes [10][11][12], position measurements for robotic systems [13][14][15], etc. [16].…”

Section: Introductionmentioning

confidence: 99%

Enhancing Positional Accuracy of the XY-Linear Stage Using Laser Tracker Feedback and IT2FLS

et al. 2023

View full text Add to dashboard Cite

This paper proposes a calibration algorithm to improve the positional accuracies of an industrial XY-linear stage. Precision positioning of these linear stages is required to maintain highly accurate object handling and manipulation. However, due to imprecisions in linear motor stages and the gearbox, static and dynamic errors exist within these manipulators that cannot be adjusted internally. In this paper, to improve the positioning accuracy of these manipulators, measurements from a laser tracker are used within an interval type-2 fuzzy logic system. The laser tracker used in this experiment is an AT960-MR, which is a highly accurate noncontact coordinate metrology equipment capable of performing highly accurate robotic measurements. To perform calibration, we use an IT2FLS to find a nonlinear correcting relationship to compensate for position errors. The IT2FLS acts on the commands given to the move stage to find the accurate position of the move stage. To train the IT2FLS, we use particle swarm optimization (PSO) for the antecedent part parameters and Moore–Penrose generalized inverse to estimate the consequent part parameters. Data are split into train/test data to test the efficacy of the proposed algorithm. It is shown that by using the proposed IT2FLS-based calibration approach, the standard deviation of the position errors can be decreased from 86.1μm to 55.9μm, which is a 35.1% improvement. Comparison results with a multilayer perceptron neural network reveal that the proposed IT2FLS-based calibration algorithm outperforms multilayer perceptron neural network for positional calibration purposes.

show abstract

Section: Introductionmentioning

confidence: 99%

Enhancing Positional Accuracy of the XY-Linear Stage Using Laser Tracker Feedback and IT2FLS

et al. 2023

View full text Add to dashboard Cite

show abstract

Augmented Reality Interface for Robot-Sensor Coordinate Registration

Nguyen¹,

Liu²,

Marvel

2023

Journal of Computing and Information Science in Engineering

View full text Add to dashboard Cite

Accurate registration of Cartesian coordinate systems is necessary to facilitate metrology-based solutions for industrial robots in production environments. Conducting coordinate registration between industrial robots and their metrological systems requires measuring multiple points in the robot's and sensor system's coordinate frames. However, operators lack intuitive tools to interface, visualize, and characterize the quality of the selected points in the robot workspace for robot-sensor coordinate registration. This paper proposes an augmented reality system for human-in-the-loop, robot-sensor coordinate registration to efficiently record and visualize the pose-dependent quality of computing the robot-sensor transformation. Furthermore, this work establishes metrics to define the relative quality of measurement points used in robot-sensor coordinate registration, which are shown by the augmented reality application. Experiments were conducted demonstrating the augmented reality environment in addition to investigating the pose-dependency of the measurement point quality. The results indicate that the proposed metrics highlight the dependency of the poses on both robot and sensor placement and that the augmented reality system can provide a human-in-the-loop interface for robot-sensor coordinate registration.

show abstract

Interval Type-2 Fuzzy Logic Control of Linear Stages in Feedback-Error-Learning Structure Using Laser Interferometer

Khanesar,

Yan,

Karaca

et al. 2024

Energies

View full text Add to dashboard Cite

The output processer of interval type-2 fuzzy logic systems (IT2FLSs) is a complex operator which performs type-reduction plus defuzzification (TR+D) tasks. In this paper, a complexity-reduced yet high-performance TR+D for IT2FLSs based on Maclaurin series approximation is utilized within a feedback-error-learning (FEL) control structure for controlling linear move stages. IT2FLSs are widely used for control purposes, as they provide extra degrees of freedom to increase control accuracies. FEL benefits from a classical controller, which is responsible for providing overall system stability, as well as a guideline for the training mechanism for IT2FLSs. The Kalman filter approach is utilized to tune IT2FLS parameters in this FEL structure. The proposed control method is applied to a linear stage in real time. Using an identification process, a model of the real-time linear stage is developed. Simulation results indicate that the proposed FEL approach using the Kalman filter as an estimator is an effective approach that outperforms the gradient descent-based FEL method and the proportional derivative (PD) classical controller. Motivated by the performance of the proposed Kalman filter-based FEL approach, it is used to control a linear move stage in real time. The position feedback of the move stage is provided by a precision laser interferometer capable of performing measurements with an accuracy of less than 1 μm. Using this measurement system in a feedback loop with the proposed control algorithm, the overall steady state of the system is less than 20 μm. The results illustrate the high-precision control capability of the proposed controller in real-time.

show abstract

Precision Robotic Milling of Fiberglass Shims in Aircraft Wing Assembly Using Laser Tracker Feedback

Cited by 3 publications

References 0 publications

Enhancing Positional Accuracy of the XY-Linear Stage Using Laser Tracker Feedback and IT2FLS

Enhancing Positional Accuracy of the XY-Linear Stage Using Laser Tracker Feedback and IT2FLS

Augmented Reality Interface for Robot-Sensor Coordinate Registration

Interval Type-2 Fuzzy Logic Control of Linear Stages in Feedback-Error-Learning Structure Using Laser Interferometer

Contact Info

Product

Resources

About