On Mathematical Modeling of the Dynamics of Multilink Systems and Exoskeletons

Borisov, Alexey V.; Kaspirovich, I. E.; Mukharlyamov, R. G.

doi:10.1134/s106423072104002x

Cited by 13 publications

(12 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The issues relating to exoskeleton comfort remain relevant even though the number of published articles and patents on the "exoskeleton" subject has significantly increased [1]. The massive, absolutely rigid links, included into exoskeleton and having a profound impact on human-machine system dynamics, is one of the reasons for that.…”

Section: Introductionmentioning

confidence: 99%

Dynamics of two-link exoskeleton support leg, considering payload and adjustable stiffness

Borisov,

Mukharlyamov

2024

Third International Scientific and Practical Symposium on Materials Science and Technology (MST-III 2023)

View full text Add to dashboard Cite

The exoskeleton comfortability issues are not solved at present, which prevents their widespread application. The study suggests a method of resolving these issues based on the variable-length links with adjustable stiffness. The paper describes the 3-D model of exoskeleton supporting leg consisting of two variable-length links with adjustable stiffness. The payload is simulated with a point mass located at the end of the second link. The link length control is implemented by adjusting the stiffness of magneto-rheological fluid in the links. The fluid stiffness depends on the applied magnetic field strength. The pivoting points are simulated with spherical hinges. The system dynamics is described by the Lagrange equations using the angles between neighbouring links and the coordinate corresponding to the link length. Inverse dynamics problem solution methods for systems with constraints stabilization are used for obtaining control torques and lengthwise forces. The animation of mechanism motion demonstrates the adequacy of the proposed simulation procedure. The proposed model can contribute to development of more comfortable exoskeletons that are simulating biomechanics of human musculoskeletal system more precisely.

show abstract

Section: Introductionmentioning

confidence: 99%

Dynamics of two-link exoskeleton support leg, considering payload and adjustable stiffness

Borisov,

Mukharlyamov

2024

Third International Scientific and Practical Symposium on Materials Science and Technology (MST-III 2023)

View full text Add to dashboard Cite

show abstract

“…The exoskeletons and anthropomorphic robots are actively developed, as evidenced by the large number of publications in this domain [5][6][7][8][9][10]. Since some simulation difficulties emerge with the models with large number of freedom degrees, it is suggested to use the smart motion control models that can be further extensively applied in designing actually working controlled robotic devices, such as an active exoskeleton for a human, or an anthropomorphic industrial robot.…”

Section: Introductionmentioning

confidence: 99%

“…The proposed exoskeleton models differ from the previously created ones 5 by using the angles between the links, which corresponds to the functioning of electric drives with reduction gears that actually change the relative angles between the links. Thereby, the predefined anthropomorphic mechanism motion is performed due to configuration link change, internal efforts, and imposed restrictions.…”

Section: Introductionmentioning

confidence: 99%

“…This is another difference of the proposed exoskeleton from the previously created models with mobility restrictions due to applying not only spherical, but also cylindrical hinges for joining the links to decrease the dimension of the system of differential equations of motion. The proposed models, as opposed to the previously considered ones 5 , more precisely emulate degrees of mobility between the links in the human musculoskeletal system. Therefore, this design can be used not only in exoskeleton development, but also in creating anthropomorphic robots, which is of great industrial importance.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Comparative analysis of exoskeleton mechanical models with mobile links having maximal mobility degrees, and their generalization for the case of n links

Konchina,

Kulikova,

Maslova

et al. 2024

Third International Conference on Optics, Computer Applications, and Materials Science (CMSD-III 2023)

View full text Add to dashboard Cite

The software, implementing mathematical models of 2D and 3D active exoskeletons with electric drives, has been developed in the environment of universal computer mathematical system "Wolfram Mathematica". Each model has the same structure and includes five mobile links. Generalization of these models for the case of arbitrary finite number of n links is made. The angles, calculated between the links of the models, are used in the software described in the article, which differ these models from the existing ones. Cylindrical hinges are used for the articulated interconnection of the links in the 2D model. As for the 3D model, the spherical hinges perfectly implement all mobility degrees available in the human musculoskeletal system. This fact also differ the proposed 3D model from the existing ones, which have limited mobility and use not only spherical, but also cylindrical hinges to join some links in order to reduce dimension of the system of differential equations of motion. The comparative analysis of the obtained mathematical models for the two mechanisms in the form of Lagrange equations of the second kind is made. The system of electromechanical equations for the model using asynchronous AC motor is listed. The solution of direct and inverse dynamics problems is given for 2D model. As for the 3D model, no numerical solution of the Cauchy problem has been obtained due to large dimension of the system of differential equations of motion and limited computing power. Therefore, the idea about exoskeleton motion control model based on artificial intelligence that needs to be developed is suggested.

show abstract

“…Экзоскелеты являются результатом интеграции людей и роботизированных механизмов. Антропоморфные роботы, экзоскелеты и бионические протезы разрабатываются достаточно активно в последнее время, о чем свидетельствует большое количество публикаций, описанных в работах [1] и патентов по этим темам.…”

Section: Introductionunclassified

Issues emerging in human musculoskeletal system simulation with mechanical and electromechanical rod structures

Blinov

Borisov

Konchina

et al. 2022

«Izvestiya vysshikh uchebnykh zavedenii. PROBLEMY ENERGETIKI»

Self Cite

View full text Add to dashboard Cite

Based on the statistical analysis of publications and patents located in the RSCI database for the keywords «exoskeleton», «anthropomorphic robot», «bionic prosthesis», interest in the research topic has been established, expressed in a significant increase in publications in recent years. It was revealed that most of the models use absolutely solid links in the form of rods.GOAL. Identification and study of problems arising in the modeling of anthropomorphic robotic systems. METHODS. Methods of mathematical modeling, analysis, comparison with a biological prototype, robotics, theoretical mechanics, electromechanics were used. RESULTS. The problem of accuracy of modeling by rod robotic systems with absolutely rigid links, a link of the human musculoskeletal system, is considered. The relative error of the accuracy of approximation by rods of a human limb is calculated, a conclusion is made about a significant error in the modeling of links. The problem of evaluating the influence of a rotating rotor of an electric motor on a mechanism model is considered. Next, the model is considered taking into account the rotating rotor and gearbox. It has been established that when modeling anthropomorphic mechanisms with rods, the problem arises of the need to take into account the dynamics of drives. An electromechanical model of a link with a DC motor is proposed. A significant increase in energy costs during the movement of the link has been established, in comparison with the model of an ideal hinge, in which the required control moment is created, which is a problem. A partial solution of the identified problems is proposed using the model of a variable length link containing three sections. CONCLUSION. The study made it possible to identify problems that arise when modeling the human musculoskeletal system with rod robotic electromechanical systems with absolutely solid links.

show abstract

On Mathematical Modeling of the Dynamics of Multilink Systems and Exoskeletons

Cited by 13 publications

References 43 publications

Dynamics of two-link exoskeleton support leg, considering payload and adjustable stiffness

Dynamics of two-link exoskeleton support leg, considering payload and adjustable stiffness

Comparative analysis of exoskeleton mechanical models with mobile links having maximal mobility degrees, and their generalization for the case of n links

Issues emerging in human musculoskeletal system simulation with mechanical and electromechanical rod structures

Contact Info

Product

Resources

About