scholarly journals Experimental Validation of Contact Dynamics for In-Hand Manipulation

Author(s):  
Roman Kolbert ◽  
Nikhil Chavan-Dafle ◽  
Alberto Rodriguez
2017 ◽  
Vol 139 (2) ◽  
Author(s):  
Alfonso Callejo ◽  
Siamak Arbatani ◽  
József Kövecses ◽  
Masoud Kalantari ◽  
Nick R. Marchand

Simulation techniques are increasingly becoming popular in recent years as a way of simulating oil drilling processes. Among them, directional drilling is a specific method that benefits enormously from such numerical techniques, inasmuch as the estimation of the wellbore curvature is crucial and cannot be properly estimated through approximate geometry methods. We present here some of the latest advances in bit contact dynamics, wellbore update algorithms, and experimental validation of side cutting, in the context of a finite element (FE) and finite segment simulation framework. The framework is based on the high-fidelity dynamic simulation of the mechanical system, including detailed geometry, large displacements, and accurate contact forces. The theoretical aspects, along with the experimental results, are thoroughly presented. Overall, this paper constitutes a step toward a more deterministic way of calculating build rates and designing downhole drilling tools.


Author(s):  
Qian Liu ◽  
Jing Cheng ◽  
Delun Li ◽  
Qingqing Wei

Abstract This brief paper emphasizes on the experimental study of a hybrid contact model (HCM) combining a traditional physical-based contact model and a data-driven error model in order to provide a more accurate description of a contact dynamics phenomenon. The physical-based contact model is employed to describe the known contact physics of a complex contact case, while the data-driven error model, which is an artificial neural network model trained from experimental data using a machine learning technique, is used to represent the inherent unmodeled factors of the contact case. A bouncing ball experiment is designed and performed to validate the model. The HCM can duplicate experimental results well, which demonstrates the feasibility and accuracy of the presented approach.


Author(s):  
Michael Boos ◽  
John McPhee

A volumetric contact dynamics model has been proposed for the purpose of generating reliable and rapid simulations of contact dynamics. Forces and moments between bodies in contact can be expressed in terms of the volume of interference between the undeformed geometries. This allows for the modelling of contact between complex geometries and relatively large contact surfaces, while being computationally less expensive than finite element methods. However, the volumetric model requires experimental validation. Models for simple geometries in contact have been developed for stationary and dynamic contact; an apparatus has been developed to experimentally validate these models. This paper focuses on validation of the normal contact models. Measurements of forces and displacements will be used to identify the parameters related to the normal force, i.e. the volumetric stiffness and hysteretic damping factor for metallic surfaces. The experimental measurements are compared with simulated results to assess the validity of the volumetric model.


Author(s):  
Michael Boos ◽  
John McPhee

A volumetric contact dynamics model has been proposed for the purpose of generating reliable and rapid simulations of contact dynamics. Forces and moments between bodies in contact can be expressed in terms of the volume of interference between the undeformed geometries. This allows for the modeling of contact between complex geometries and relatively large contact surfaces, while being computationally less expensive than finite element methods. However, the volumetric model requires experimental validation. Models for simple geometries in contact have been developed for stationary and dynamic contact, and an apparatus has been developed to experimentally validate these models. This paper focuses on validation of the normal contact models. Measurements of forces and displacements will be used to identify the parameters related to the normal force, i.e., the volumetric stiffness and hysteretic damping factor for metallic surfaces. The experimental measurements are compared with simulated results to assess the validity of the volumetric model.


2020 ◽  
Vol 63 (1) ◽  
pp. 109-124
Author(s):  
Carly Jo Hosbach-Cannon ◽  
Soren Y. Lowell ◽  
Raymond H. Colton ◽  
Richard T. Kelley ◽  
Xue Bao

Purpose To advance our current knowledge of singer physiology by using ultrasonography in combination with acoustic measures to compare physiological differences between musical theater (MT) and opera (OP) singers under controlled phonation conditions. Primary objectives addressed in this study were (a) to determine if differences in hyolaryngeal and vocal fold contact dynamics occur between two professional voice populations (MT and OP) during singing tasks and (b) to determine if differences occur between MT and OP singers in oral configuration and associated acoustic resonance during singing tasks. Method Twenty-one singers (10 MT and 11 OP) were included. All participants were currently enrolled in a music program. Experimental procedures consisted of sustained phonation on the vowels /i/ and /ɑ/ during both a low-pitch task and a high-pitch task. Measures of hyolaryngeal elevation, tongue height, and tongue advancement were assessed using ultrasonography. Vocal fold contact dynamics were measured using electroglottography. Simultaneous acoustic recordings were obtained during all ultrasonography procedures for analysis of the first two formant frequencies. Results Significant oral configuration differences, reflected by measures of tongue height and tongue advancement, were seen between groups. Measures of acoustic resonance also showed significant differences between groups during specific tasks. Both singer groups significantly raised their hyoid position when singing high-pitched vowels, but hyoid elevation was not statistically different between groups. Likewise, vocal fold contact dynamics did not significantly differentiate the two singer groups. Conclusions These findings suggest that, under controlled phonation conditions, MT singers alter their oral configuration and achieve differing resultant formants as compared with OP singers. Because singers are at a high risk of developing a voice disorder, understanding how these two groups of singers adjust their vocal tract configuration during their specific singing genre may help to identify risky vocal behavior and provide a basis for prevention of voice disorders.


2015 ◽  
Vol 53 (01) ◽  
Author(s):  
L Spomer ◽  
CGW Gertzen ◽  
D Häussinger ◽  
H Gohlke ◽  
V Keitel

2018 ◽  
Vol 138 (8) ◽  
pp. 651-658 ◽  
Author(s):  
Keisuke Shirasaki ◽  
Naotaka Okada ◽  
Kenichiro Sano ◽  
Hideki Iwatsuki

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