Sampling strategy design for dimensional measurement of geometric features using coordinate measuring machine

Uncertainty is a key concept in any environment which involves measurements to ensure process quality: a trade-off has to be found between measurement costs, which increase as uncertainty lowers, and costs related to measurement errors. In mechanics, geometrical conformance is a common requirement. Two similar standards series deal with the problem of uncertainty in geometrical error estimate: ASME B89.7.3 and ISO 14253. Geometrical inspection is often performed by means of a “Coordinate Measuring Machine” (CMM). For a CMM, a trade off between measurement and errors costs may be found by optimizing the sampling strategy. In this work a cost function will be proposed as support for finding a trade-off between measurement uncertainty and costs. This function may be optimized by means of an heuristic algorithm. The method will involve repeated measurements of calibrated parts to evaluate uncertainty (like in ISO/TS 15330-3). A case study will be proposed.

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Application of the sampling strategies in the inspection process

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

10.1177/0954405416684157 ◽

2017 ◽

Vol 231 (4) ◽

pp. 565-575 ◽

Cited By ~ 2

Author(s):

Syed Hammad Mian ◽

Abdulrahman M Al-Ahmari

Keyword(s):

Sample Size ◽

Adaptive Sampling ◽

Sampling Methods ◽

Fundamental Problem ◽

Coordinate Measuring Machine ◽

Sampling Strategy ◽

Point Distribution ◽

Coordinate Metrology ◽

Inspection Process ◽

Measuring Machine

The selection of appropriate sample size and point distribution on the measuring surface has been a fundamental problem in the contemporary coordinate metrology. It is usually resolved by the users depending on their instinct or prior experience. As a result, inspection results have to be compromised between accuracy and measurement time. However, to deliver quality products in minimum time, effort, and cost, a reliable and an efficient sampling plan is mandatory. Although there have been a remarkable progress due to the development of various procedures for computing the sample size and selecting the appropriate point distribution, still users are inconversant with the characteristics and applications of the available sampling methods due to the absence of a proper review. Accordingly, a systematic review, giving insight into the various strategies available for the sample size and the point distribution, is presented. In this article, different algorithms and their application in the estimation of sample size and point distribution have been reviewed comprehensively. The classification of sampling methods and the importance of adaptive sampling have also been described. It has been concluded that the effectiveness of inspection process or the performance of coordinate measuring machine can be escalated through the application of a suitable sampling strategy. Therefore, the metrologists should either develop an effective method for defining sampling strategy or select the most suitable method from the available resources before carrying out the inspection process.

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Analysis and Realization of Sampling Strategy in Coordinate Metrology

Mathematical Problems in Engineering ◽

10.1155/2019/9574153 ◽

2019 ◽

Vol 2019 ◽

pp. 1-19 ◽

Cited By ~ 1

Author(s):

Syed Hammad Mian ◽

Abdulrahman Al-Ahmari ◽

Hisham Alkhalefah

Keyword(s):

Grid Point ◽

Coordinate Measuring Machine ◽

Sampling Strategy ◽

Surface Characteristics ◽

Optimization Techniques ◽

Point Distribution ◽

Solution Approach ◽

Coordinate Metrology ◽

Measuring Machine ◽

Distribution Algorithms

The stringent customer demands and competitive market emphasize the importance of efficient and effective inspection in industrial metrology. Therefore, the implementation of an appropriate sampling strategy, i.e., the number of points and their distribution, has become very important in the inspection process using a coordinate measuring machine. Moreover, the quality of inspection results has frequently been influenced by sampling plan as well as workpiece size and surface characteristics. It has been an indispensable problem in the present-day measurement processes. Thus, this paper investigates various sample sizes and different point distribution algorithms that can be employed in the evaluation of form error. The effect of specimen size and surface quality on the sampling strategy has also been investigated. Furthermore, this work employs a fuzzy based Technique for Order Performance by Similarity to Ideal Solution approach to realize the best sampling strategy. The results have demonstrated the significance of robust optimization techniques as well as the importance of a suitable sampling strategy in coordinate metrology. This study has also established that Poisson point distribution achieved the best accuracy and the Grid point distribution had taken the least measurement time.

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An investigation of Outlier Detection Procedures for CMM Measurement Data

MATEC Web of Conferences ◽

10.1051/matecconf/201822004002 ◽

2018 ◽

Vol 220 ◽

pp. 04002 ◽

Cited By ~ 1

Author(s):

Petr Chelishchev ◽

Aleksandr Popov ◽

Knut Sørby

Keyword(s):

Outlier Detection ◽

Cross Sections ◽

Experimental Verification ◽

Measurement Data ◽

Coordinate Measuring Machine ◽

Data Sets ◽

Dimensional Measurement ◽

Measuring Machine ◽

Simulation Results

The paper analyses methods for outlier detection in dimensional measurement. The cross sections of an internal cylinder were inspected by CMM (coordinate measuring machine), and received data sets were employed for further investigation. The efficiency of Rosner’s and Grubbs’ methods for excluding outliers from the measuring data had been estimated. The method of Rosner had been defined as the most effective for this case study. The simulation results were confirmed by experimental verification.

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Assessment of the Change in Volume of Acetabular Cups Using a Coordinate Measuring Machine

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/pime_proc_1994_208_280_02 ◽

1994 ◽

Vol 208 (3) ◽

pp. 151-158 ◽

Cited By ~ 25

Author(s):

B Derbyshire ◽

C S Hardaker ◽

J Fisher ◽

D Dowson ◽

K Brummitt

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Coordinate Measuring Machine ◽

Coordinate Measuring Machines ◽

Acetabular Cup ◽

Wear Rates ◽

Dimensional Measurement ◽

Hip Simulator ◽

Measuring Machine ◽

Ultra High Molecular Weight

It is necessary to accurately measure the change in volume of ultra-high molecular weight polyethylene (UHMWPE) acetabular cups during hip simulator tests in order to determine wear rates. This study investigates the accuracy of dimensional measurement of an acetabular cup socket using two different coordinate measuring machines. The repeatability of the measurement was found to be primarily dependent upon the accuracy of relocation of the datum before each set of measurements.

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Surface Plate based Method for Quick Check CMM Accuracy Measurement

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.j9421.0881019 ◽

2019 ◽

Vol 8 (10) ◽

pp. 2659-2662

Keyword(s):

Low Cost ◽

Coordinate Measuring Machine ◽

Entire Volume ◽

Accuracy Measurement ◽

Dimensional Measurement ◽

Cost Surface ◽

Measuring Machine ◽

Surface Plate ◽

Made In ◽

Indian Scenario

Coordinate Measuring Machine is now mandatory in Industries for not only dimensional measurement but also form measurement of jobs. However, due to changes in temperature in Indian Scenario, Rigidity of guide ways, frictional bearings, it is always susceptible for error development. These errors if not addressed, integrates into dimensional measurement of workpart, which remains induced due to measurement system error. Best position of job in entire volume of CMM affects the accuracy of measurand and is the deciding factor in CMM measurement. An attempt is made in this paper, to establish low cost surface plate based method for quick check CMM accuracy measurement by operator only without requirement of Laser CMM expert. The outcome of method depicts closeness within 3 µm with laser interferometer. This saves at least two lakhs rupees per three months and the total saving will be 6 lakhs rupees, annually.

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