Machine learning-based method for linearization and error compensation of a novel absolute rotary encoder

Iafolla, L.; Filipozzi, Massimiliano; Freund, Sara; Zam, Azhar; Rauter, Georg; Cattin, Philippe C.

doi:10.1016/j.measurement.2020.108547

Cited by 9 publications

(4 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With the development of aerospace and robotics technology in China, the miniaturization of absolute photoelectric encoders has been highly valued by enterprises and research institutes [ 6 ]. At present, the encoding methods for miniaturized absolute optoelectronic encoders mainly include Gray code, matrix code, single-ring Gray code, M-sequence code, and image encoding [ 7 , 8 , 9 , 10 ]. The matrix encoding method characterizes the encoding of different bits of traditional Gray codes on a circular code track, and its final output is the same as that of traditional Gray codes, but the number of code disk turns is reduced [ 11 , 12 ].…”

Section: Introductionmentioning

confidence: 99%

A 19-Bit Small Absolute Matrix Encoder

Geng,

Cao,

Shang

et al. 2024

Sensors

View full text Add to dashboard Cite

With the application of encoders in artificial intelligence and aerospace, the demand for the miniaturization and high measurement accuracy of encoders is increasing. To solve this problem, a new absolute matrix encoder is proposed in this paper, which can realize 19-bit matrix coding by engraving two circles of matrix code, and has the advantages of fewer circles of code disk engraving and higher measurement accuracy. This article mainly focuses on the design of a new matrix code disk, encoding and decoding methods, decoding circuit design, Matlab simulation analysis, and experimental error analysis. The experimental results show that the encoder designed in this paper achieves ultra-small volume Φ30 mm × 20 mm, and the angle measurement accuracy is 2.57”.

show abstract

Section: Introductionmentioning

confidence: 99%

A 19-Bit Small Absolute Matrix Encoder

Geng,

Cao,

Shang

et al. 2024

Sensors

View full text Add to dashboard Cite

show abstract

“…[11] utilized a hybrid algorithm which integrates Fourier expansion, back-propagation neural network and genetic algorithm (FE-GABPNN) to compensate the error of an articulated coordinate measurement machine in the presence of temperature variations. Also, an original optical rotary encoder was proposed in [12], relying on the recognition of an image uniquely identifying the absolute rotor angle; ML techniques were adopted for sector classification and angle regression.…”

Section: Introductionmentioning

confidence: 99%

Absolute Two-Tracked Optical Rotary Encoders Based on Vernier Method

Dalboni

Soldati

2023

IEEE Trans. Instrum. Meas.

View full text Add to dashboard Cite

Driving synchronous machines requires early and accurate knowledge of the absolute position of the rotor; current solutions based on resolvers, sin-cos or absolute encoders are complex, bulky and costly. Hence, in this work two variants of absolute rotary encoder based on Vernier method are analyzed. One, already discussed in the literature, displays the Vernier scale across the whole circumference (full-Vernier), the other shows half Vernier traces over the entire perimeter (half-Vernier), which is an original feature. Both implementations are characterized by only two tracks and as many sensors: the proposed conditioning algorithms provide the absolute angular position as a function of the time delays between the wave edges generated by the two traces, thus being of easy implementation on low-cost MCUs. The Vernier encoders are also compared with state-of-the-art absolute and relative solutions, i.e. incremental, binary and Graycode encoders. Experimental tests are carried out to assess the accuracy of the proposed sensors. The investigation shows that (i) the full-Vernier cannot provide, in practice, a reliable estimate of the direction of rotation and of the actual angular sector without resorting to a third sensor; (ii) the half-Vernier produces a trusty measurement of the absolute angle and velocity and (iii) can give a reliable position result with less than 30°shaft turn, but (iv) it can suffer from marginal performance degradation at low velocities in conjunction with high accelerations. Compared to the Gray encoder, the half-Vernier provides a simpler and more compact hardware for a given resolution, similar to that of an incremental encoder, at the expense of a small accuracy reduction at low speed.

show abstract

“…However, compared with linear systems, the research on micro-drive rotary systems is scarce and dated [ 28 ]. In addition, the positional accuracy of linear motion can reach the nanometer level [ 29 , 30 ], but the rotary motion is only at the arc-second (″) level [ 31 , 32 , 33 , 34 ].…”

Section: Introductionmentioning

confidence: 99%

Positioning Performance of a Sub-Arc-Second Micro-Drive Rotary System

Zhang

Yang

et al. 2021

Micromachines

View full text Add to dashboard Cite

In the macro/micro dual-drive rotary system, the micro-drive system compensates for the position error of the macro-drive system. To realize the sub-arc-second (i.e., level of 1″–0.1″) positioning of the macro/micro dual-drive rotary system, it is necessary to study the positioning performance of the sub-arc-second micro-drive rotary system. In this paper, we designed a sub-arc-second micro-drive rotary system consisting of a PZT (piezoelectric actuator) and a micro rotary mechanism, and used simulation and experimental methods to study the positioning performance of the system. First, the micro-drive rotary system was developed to provide ultra-precise rotary motion. In this system, the PZT has ultrahigh resolution at a level of 0.1 nanometers in linear motion; a micro rotating mechanism was designed according to the composite motion principle of the flexible hinge, which could transform the linear motion of piezoelectric ceramics into rotating motion accurately. Second, the drive performance was analyzed based on the drive performance experiment. Third, kinematics, simulation, and experiments were carried out to analyze the transformation performance of the system. Finally, the positioning performance equation of the system was established based on the two performance equations, and the maximum rotary displacements and positioning error of the system were calculated. The study results showed that the system can provide precision motion at the sub-arc-second and good linearity of motion. This study has a certain reference value in ultra-precision positioning and micromachining for research on rotary motion systems at the sub-arc-second level.

show abstract

Machine learning-based method for linearization and error compensation of a novel absolute rotary encoder

Cited by 9 publications

References 24 publications

A 19-Bit Small Absolute Matrix Encoder

A 19-Bit Small Absolute Matrix Encoder

Absolute Two-Tracked Optical Rotary Encoders Based on Vernier Method

Positioning Performance of a Sub-Arc-Second Micro-Drive Rotary System

Contact Info

Product

Resources

About