Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers
Measurement of force on a micro- or nano-Newton scale is important when exploring the mechanical properties of materials in the biophysics and nanomechanical fields. The atomic force microscope (AFM) is widely used in microforce measurement. The cantilever probe works as an AFM force sensor, and the...
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| Format: | Article |
| Language: | English |
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MDPI AG
2015-03-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/15/3/5865 |
| _version_ | 1828114088680488960 |
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| author | Yunpeng Song Sen Wu Linyan Xu Xing Fu |
| author_facet | Yunpeng Song Sen Wu Linyan Xu Xing Fu |
| author_sort | Yunpeng Song |
| collection | DOAJ |
| description | Measurement of force on a micro- or nano-Newton scale is important when exploring the mechanical properties of materials in the biophysics and nanomechanical fields. The atomic force microscope (AFM) is widely used in microforce measurement. The cantilever probe works as an AFM force sensor, and the spring constant of the cantilever is of great significance to the accuracy of the measurement results. This paper presents a normal spring constant calibration method with the combined use of an electromagnetic balance and a homemade AFM head. When the cantilever presses the balance, its deflection is detected through an optical lever integrated in the AFM head. Meanwhile, the corresponding bending force is recorded by the balance. Then the spring constant can be simply calculated using Hooke’s law. During the calibration, a feedback loop is applied to control the deflection of the cantilever. Errors that may affect the stability of the cantilever could be compensated rapidly. Five types of commercial cantilevers with different shapes, stiffness, and operating modes were chosen to evaluate the performance of our system. Based on the uncertainty analysis, the expanded relative standard uncertainties of the normal spring constant of most measured cantilevers are believed to be better than 2%. |
| first_indexed | 2024-04-11T12:19:29Z |
| format | Article |
| id | doaj.art-90b6ad8701e34c658e7a7f286d6702c7 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T12:19:29Z |
| publishDate | 2015-03-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-90b6ad8701e34c658e7a7f286d6702c72022-12-22T04:24:08ZengMDPI AGSensors1424-82202015-03-011535865588310.3390/s150305865s150305865Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM CantileversYunpeng Song0Sen Wu1Linyan Xu2Xing Fu3State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, ChinaState Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, ChinaState Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, ChinaState Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, ChinaMeasurement of force on a micro- or nano-Newton scale is important when exploring the mechanical properties of materials in the biophysics and nanomechanical fields. The atomic force microscope (AFM) is widely used in microforce measurement. The cantilever probe works as an AFM force sensor, and the spring constant of the cantilever is of great significance to the accuracy of the measurement results. This paper presents a normal spring constant calibration method with the combined use of an electromagnetic balance and a homemade AFM head. When the cantilever presses the balance, its deflection is detected through an optical lever integrated in the AFM head. Meanwhile, the corresponding bending force is recorded by the balance. Then the spring constant can be simply calculated using Hooke’s law. During the calibration, a feedback loop is applied to control the deflection of the cantilever. Errors that may affect the stability of the cantilever could be compensated rapidly. Five types of commercial cantilevers with different shapes, stiffness, and operating modes were chosen to evaluate the performance of our system. Based on the uncertainty analysis, the expanded relative standard uncertainties of the normal spring constant of most measured cantilevers are believed to be better than 2%.http://www.mdpi.com/1424-8220/15/3/5865AFM cantilevernormal spring constantcalibrationbalanceuncertainty estimation |
| spellingShingle | Yunpeng Song Sen Wu Linyan Xu Xing Fu Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers Sensors AFM cantilever normal spring constant calibration balance uncertainty estimation |
| title | Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers |
| title_full | Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers |
| title_fullStr | Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers |
| title_full_unstemmed | Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers |
| title_short | Accurate Calibration and Uncertainty Estimation of the Normal Spring Constant of Various AFM Cantilevers |
| title_sort | accurate calibration and uncertainty estimation of the normal spring constant of various afm cantilevers |
| topic | AFM cantilever normal spring constant calibration balance uncertainty estimation |
| url | http://www.mdpi.com/1424-8220/15/3/5865 |
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