Point of optimal kinematic error: Improvement of the instantaneous helical pivot method for locating centers of rotation

[EN] This paper proposes a variation of the instantaneous helical pivot technique for locating centers of rotation. The point of optimal kinematic error (POKE), which minimizes the velocity at the center of rotation, may be obtained by just adding a weighting factor equal to the square of angular velocity in Woltring's equation of the pivot of instantaneous helical axes (PIHA). Calculations are simplified with respect to the original method, since it is not necessary to make explicit calculations of the helical axis, and the effect of accidental errors is reduced. The improved performance of this method was validated by simulations based on a functional calibration task for the gleno-humeral joint center. Noisy data caused a systematic dislocation of the calculated center of rotation towards the center of the arm marker cluster. This error in PIHA could even exceed the effect of soft tissue artifacts associated to small and medium deformations, but it was successfully reduced by the POKE estimation.This work has been funded by the Spanish Government (Grants DPI2009-13830-C02-01, DPI2009-13830-CO2-02, DPI2010-20814-CO2-01, DPI2010-20814-CO2-02).De Rosario Martínez, H.; Page Del Pozo, AF.; Mata Amela, V. (2014). Point of optimal kinematic error: Improvement of the instantaneous helical pivot method for locating centers of rotation. Journal of Biomechanics. 47(7):1742-1747. doi:10.1016/j.jbiomech.2014.02.003S1742174747

Automatic selection of the Groebner Basis' monomial order employed for the synthesis of the inverse kinematic model of non-redundant open-chain robotic systems

This is an Author's Accepted Manuscript of an article published in José Guzmán-Giménez, Ángel Valera Fernández, Vicente Mata Amela & Miguel Ángel Díaz-Rodríguez (2023) Automatic selection of the Groebner Basis¿ monomial order employed for the synthesis of the inverse kinematic model of non-redundant open-chain robotic systems, Mechanics Based Design of Structures and Machines, 51:5, 2458-2480, DOI: 10.1080/15397734.2021.1899829 [copyright Taylor & Francis], available online at: http://www.tandfonline.com/10.1080/15397734.2021.1899829[EN] The methods most commonly used to synthesize the Inverse Kinematic Model (IKM) of open-chain robotic systems strongly depend on the robot's geometry, which make them difficult to systematize. In a previous work we presented a systematic procedure that relies on Groebner Bases to synthesize the IKM of non-redundant open-chain robots. This study expands the developed procedure with a methodology for the automatic selection of the basis' monomial order. The procedure's inputs are the robot's Denavit-Hartenberg parameters and the movement range of its actuators, while the output is the synthesized IKM, ready to be used in the robot's control system or in a simulation of its behavior. This procedure can synthesize the IKM of a wide range of open-chain robotic systems, such as Cartesian robots, SCARA, non-redundant multi-legged robots, and all non-redundant manipulators that satisfy the in-line wrist condition. The procedure's performance is assessed through two study cases of open-chain robots: a walking hexapod and a PUMA manipulator. The optimal monomial order is successfully identified for all cases. Also the output errors of the synthesized IKMs are negligible when evaluated in their corresponding workspaces, while their computation times are comparable to those required by the kinematic models calculated by traditional methods.This research was partially funded by Plan Nacional de IthornDthorni, Agencia Estatal de Investigacion del Ministerio de Economia, Industria y Competitividad del Gobierno de Espana, in the project FEDER-CICYT DPI201784201-R.Guzmán-Giménez, J.; Valera Fernández, Á.; Mata Amela, V.; Díaz-Rodríguez, MÁ. (2023). Automatic selection of the Groebner Basis' monomial order employed for the synthesis of the inverse kinematic model of non-redundant open-chain robotic systems. Mechanics Based Design of Structures and Machines. 51(5):2458-2480. https://doi.org/10.1080/15397734.2021.18998292458248051

Synthesis of the Inverse Kinematic Model of Non-Redundant Open-Chain Robotic Systems Using Groebner Basis Theory

[EN] One of the most important elements of a robot's control system is its Inverse Kinematic Model (IKM), which calculates the position and velocity references required by the robot's actuators to follow a trajectory. The methods that are commonly used to synthesize the IKM of open-chain robotic systems strongly depend on the geometry of the analyzed robot. Those methods are not systematic procedures that could be applied equally in all possible cases. This project presents the development of a systematic procedure to synthesize the IKM of non-redundant open-chain robotic systems using Groebner Basis theory, which does not depend on the geometry of the robot's structure. The inputs to the developed procedure are the robot's Denavit-Hartenberg parameters, while the output is the IKM, ready to be used in the robot's control system or in a simulation of its behavior. The Groebner Basis calculation is done in a two-step process, first computing a basis with Faugere's F4 algorithm and a grevlex monomial order, and later changing the basis with the FGLM algorithm to the desired lexicographic order. This procedure's performance was proved calculating the IKM of a PUMA manipulator and a walking hexapod robot. The errors in the computed references of both IKMs were absolutely negligible in their corresponding workspaces, and their computation times were comparable to those required by the kinematic models calculated by traditional methods. The developed procedure can be applied to all Cartesian robotic systems, SCARA robots, all the non-redundant robotic manipulators that satisfy the in-line wrist condition, and any non-redundant open-chain robot whose IKM should only solve the positioning problem, such as multi-legged walking robots.This research was partially funded by Plan Nacional de I+D+i, Agencia Estatal de Investigacion del Ministerio de Economia, Industria y Competitividad del Gobierno de Espana, in the project FEDER-CICYT DPI2017-84201-R.Guzmán-Giménez, J.; Valera Fernández, Á.; Mata Amela, V.; Díaz-Rodríguez, MÁ. (2020). Synthesis of the Inverse Kinematic Model of Non-Redundant Open-Chain Robotic Systems Using Groebner Basis Theory. Applied Sciences. 10(8):1-22. https://doi.org/10.3390/app10082781S122108Atique, M. M. U., Sarker, M. R. I., & Ahad, M. A. R. (2018). Development of an 8DOF quadruped robot and implementation of Inverse Kinematics using Denavit-Hartenberg convention. Heliyon, 4(12), e01053. doi:10.1016/j.heliyon.2018.e01053Flanders, M., & Kavanagh, R. C. (2015). Build-A-Robot: Using virtual reality to visualize the Denavit-Hartenberg parameters. Computer Applications in Engineering Education, 23(6), 846-853. doi:10.1002/cae.21656Özgür, E., & Mezouar, Y. (2016). Kinematic modeling and control of a robot arm using unit dual quaternions. Robotics and Autonomous Systems, 77, 66-73. doi:10.1016/j.robot.2015.12.005Wang, X., Han, D., Yu, C., & Zheng, Z. (2012). The geometric structure of unit dual quaternion with application in kinematic control. Journal of Mathematical Analysis and Applications, 389(2), 1352-1364. doi:10.1016/j.jmaa.2012.01.016Barrientos, A., Álvarez, M., Hernández, J. D., del Cerro, J., & Rossi, C. (2012). Modelado de Caden as Cinemáticas mediante Matrices de Desplazamiento. Una alternativa al método de Denavit-Hartenberg. Revista Iberoamericana de Automática e Informática Industrial RIAI, 9(4), 371-382. doi:10.1016/j.riai.2012.09.004Virgil Petrescu, R. V., Aversa, R., Apicella, A., Mirsayar, M., Kozaitis, S., Abu-Lebdeh, T., & Tiberiu Petrescu, F. I. (2017). Geometry and Inverse Kinematic at the MP3R Mobile Systems. Journal of Mechatronics and Robotics, 1(2), 58-65. doi:10.3844/jmrsp.2017.58.65Chen, S., Luo, M., Abdelaziz, O., & Jiang, G. (2017). A general analytical algorithm for collaborative robot (cobot) with 6 degree of freedom (DOF). 2017 International Conference on Applied System Innovation (ICASI). doi:10.1109/icasi.2017.7988522Bouzgou, K., & Ahmed-Foitih, Z. (2014). Geometric modeling and singularity of 6 DOF Fanuc 200IC robot. Fourth edition of the International Conference on the Innovative Computing Technology (INTECH 2014). doi:10.1109/intech.2014.6927745Mahajan, A., Singh, H. P., & Sukavanam, N. (2017). An unsupervised learning based neural network approach for a robotic manipulator. International Journal of Information Technology, 9(1), 1-6. doi:10.1007/s41870-017-0002-2Duka, A.-V. (2014). Neural Network based Inverse Kinematics Solution for Trajectory Tracking of a Robotic Arm. Procedia Technology, 12, 20-27. doi:10.1016/j.protcy.2013.12.451Toshani, H., & Farrokhi, M. (2014). Real-time inverse kinematics of redundant manipulators using neural networks and quadratic programming: A Lyapunov-based approach. Robotics and Autonomous Systems, 62(6), 766-781. doi:10.1016/j.robot.2014.02.005Rokbani, N., & Alimi, A. M. (2013). Inverse Kinematics Using Particle Swarm Optimization, A Statistical Analysis. Procedia Engineering, 64, 1602-1611. doi:10.1016/j.proeng.2013.09.242Jiang, G., Luo, M., Bai, K., & Chen, S. (2017). A Precise Positioning Method for a Puncture Robot Based on a PSO-Optimized BP Neural Network Algorithm. Applied Sciences, 7(10), 969. doi:10.3390/app7100969Köker, R. (2013). A genetic algorithm approach to a neural-network-based inverse kinematics solution of robotic manipulators based on error minimization. Information Sciences, 222, 528-543. doi:10.1016/j.ins.2012.07.051Rokbani, N., Casals, A., & Alimi, A. M. (2014). IK-FA, a New Heuristic Inverse Kinematics Solver Using Firefly Algorithm. Computational Intelligence Applications in Modeling and Control, 369-395. doi:10.1007/978-3-319-11017-2_15Buchberger, B. (2001). Multidimensional Systems and Signal Processing, 12(3/4), 223-251. doi:10.1023/a:1011949421611Kendricks, K. D. (2013). A kinematic analysis of the gmf a-510 robot: An introduction and application of groebner basis theory. Journal of Interdisciplinary Mathematics, 16(2-03), 147-169. doi:10.1080/09720502.2013.800304Wang, Y., Hang, L., & Yang, T. (2006). Inverse Kinematics Analysis of General 6R Serial Robot Mechanism Based on Groebner Base. Frontiers of Mechanical Engineering in China, 1(1), 115-124. doi:10.1007/s11465-005-0022-7Abbasnejad, G., & Carricato, M. (2015). Direct Geometrico-static Problem of Underconstrained Cable-Driven Parallel Robots With $n$ Cables. IEEE Transactions on Robotics, 31(2), 468-478. doi:10.1109/tro.2015.2393173Rameau, J.-F., & Serré, P. (2015). Computing mobility condition using Groebner basis. Mechanism and Machine Theory, 91, 21-38. doi:10.1016/j.mechmachtheory.2015.04.003Xiguang Huang, & Guangpin He. (2009). Forward kinematics of the general Stewart-Gough platform using Gröbner basis. 2009 International Conference on Mechatronics and Automation. doi:10.1109/icma.2009.5246088Uchida, T., & McPhee, J. (2012). Using Gröbner bases to generate efficient kinematic solutions for the dynamic simulation of multi-loop mechanisms. Mechanism and Machine Theory, 52, 144-157. doi:10.1016/j.mechmachtheory.2012.01.015Faugère, J.-C. (2010). FGb: A Library for Computing Gröbner Bases. Lecture Notes in Computer Science, 84-87. doi:10.1007/978-3-642-15582-6_17Faugére, J.-C. (1999). A new efficient algorithm for computing Gröbner bases (F4). Journal of Pure and Applied Algebra, 139(1-3), 61-88. doi:10.1016/s0022-4049(99)00005-5Faugère, J. C., Gianni, P., Lazard, D., & Mora, T. (1993). Efficient Computation of Zero-dimensional Gröbner Bases by Change of Ordering. Journal of Symbolic Computation, 16(4), 329-344. doi:10.1006/jsco.1993.1051Salzer, H. E. (1960). A note on the solution of quartic equations. Mathematics of Computation, 14(71), 279-279. doi:10.1090/s0025-5718-1960-0117882-

Hybrid force/position control for a 3-DOF 1T2R parallel robot: Implementation, simulations and experiments

"This is an Author's Accepted Manuscript of an article published in Cazalilla, José, Marina Vallés, Ángel Valera, Vicente Mata, and Miguel Díaz-Rodríguez. 2016. Hybrid Force/Position Control for a 3-DOF 1T2R Parallel Robot: Implementation, Simulations and Experiments. Mechanics Based Design of Structures and Machines 44 (1 2). Informa UK Limited: 16 31. doi:10.1080/15397734.2015.1030679, available online at: https://www.tandfonline.com/doi/full/10.1080/15397734.2015.1030679."[EN] A robot interacting with the environment requires that the end effector \hboxposition is tracked and that the forces of contact are kept below certain reference values. For instance, in a rehabilitation session using a robotic device, the contact forces are limited by the allowed strength of the human limbs and their complex-joints. In these cases, a control scheme which considers both position and force control is essential to avoid damage to either the end effector or the object interacting with the robot. This paper therefore develops a real-time force/position control scheme for a three-DOF parallel robot whose end effector holds a DOF one translation (1T) and two rotations (2R). The implemented hybrid force/position control considers, as a reference, the normal force on the mobile platform, which is measured by means of a load cell installed on the platform. The position control is designed to track the orientations of the robot either in joint or task space using a model-based control scheme with identified parameters. Moreover, the force control is based on a PD action. The control scheme is developed through simulations, before being applied to an actual parallel robot. The findings show that with the implemented controller, the actual robot accomplishes the reference values for the normal force on the mobile platform, while at the same time the platform accurately follows the required angular orientation.The authors wish to thank the Plan Nacional de I+D, Comision Interministerial de Ciencia y Tecnologia (FEDER-CICYT) for the partial funding of this study under the projects DPI2011-28507-C02-01 and DPI2013-44227-R. This work was also partially supported by the Fondo Nacional de Ciencia, Tecnologia e Innovacion (FONACIT-Venezuela).Cazalilla, J.; Vallés Miquel, M.; Valera Fernández, Á.; Mata Amela, V.; Díaz-Rodríguez, M. (2016). Hybrid force/position control for a 3-DOF 1T2R parallel robot: Implementation, simulations and experiments. Mechanics Based Design of Structures and Machines. 44(1-2):16-31. https://doi.org/10.1080/15397734.2015.1030679S1631441-2Åström, K. J., & Murray, R. M. (2008). Feedback Systems. doi:10.1515/9781400828739Bellakehal, S., Andreff, N., Mezouar, Y., & Tadjine, M. (2011). Force/position control of parallel robots using exteroceptive pose measurements. Meccanica, 46(1), 195-205. doi:10.1007/s11012-010-9411-zCao, R., Gao, F., Zhang, Y., Pan, D., & Chen, W. (2014). A New Parameter Design Method of a 6-DOF Parallel Motion Simulator for a Given Workspace. Mechanics Based Design of Structures and Machines, 43(1), 1-18. doi:10.1080/15397734.2014.904234Carretero, J. A., Podhorodeski, R. P., Nahon, M. A., & Gosselin, C. M. (1999). Kinematic Analysis and Optimization of a New Three Degree-of-Freedom Spatial Parallel Manipulator. Journal of Mechanical Design, 122(1), 17-24. doi:10.1115/1.533542Clavel, R. (1988). DELTA, a fast robot with parallel geometry.Proceedings of 18th International Symposium on Industrial Robot, Lausanne, April, 91–100.Díaz-Rodríguez, M., Mata, V., Valera, Á., & Page, Á. (2010). A methodology for dynamic parameters identification of 3-DOF parallel robots in terms of relevant parameters. Mechanism and Machine Theory, 45(9), 1337-1356. doi:10.1016/j.mechmachtheory.2010.04.007Diaz-Rodriguez, M., Valera, A., Mata, V., & Valles, M. (2013). Model-Based Control of a 3-DOF Parallel Robot Based on Identified Relevant Parameters. IEEE/ASME Transactions on Mechatronics, 18(6), 1737-1744. doi:10.1109/tmech.2012.2212716Farhat, N., Mata, V., Page, Á., & Valero, F. (2008). Identification of dynamic parameters of a 3-DOF RPS parallel manipulator. Mechanism and Machine Theory, 43(1), 1-17. doi:10.1016/j.mechmachtheory.2006.12.011Garg, A., Vikram, C. S., Gupta, S., Sutar, M. K., Pathak, P. M., Mehta, N. K., … Gupta, V. K. (2014). Design and Development of In Vivo Robot for Biopsy. Mechanics Based Design of Structures and Machines, 42(3), 278-295. doi:10.1080/15397734.2014.898587Gough, V. E., Whitehall, S. G. (1962). Universal tire test machine.Proceedings of 9th International Technical Congress FISITA, pp. 117–135.García de Jalón, J., & Bayo, E. (1994). Kinematic and Dynamic Simulation of Multibody Systems. Mechanical Engineering Series. doi:10.1007/978-1-4612-2600-0Lee, K.-M., & Arjunan, S. (1991). A three-degrees-of-freedom micromotion in-parallel actuated manipulator. IEEE Transactions on Robotics and Automation, 7(5), 634-641. doi:10.1109/70.97875Li, Y., & Xu, Q. (2007). Design and Development of a Medical Parallel Robot for Cardiopulmonary Resuscitation. IEEE/ASME Transactions on Mechatronics, 12(3), 265-273. doi:10.1109/tmech.2007.897257Merlet, J.-P. (2000). Parallel Robots. Solid Mechanics and Its Applications. doi:10.1007/978-94-010-9587-7Pierrot, F., Nabat, V., Company, O., Krut, S., & Poignet, P. (2009). Optimal Design of a 4-DOF Parallel Manipulator: From Academia to Industry. IEEE Transactions on Robotics, 25(2), 213-224. doi:10.1109/tro.2008.2011412Rosillo, N., Valera, A., Benimeli, F., Mata, V., & Valero, F. (2011). Real‐time solving of dynamic problem in industrial robots. Industrial Robot: An International Journal, 38(2), 119-129. doi:10.1108/01439911111106336Steward, D. A. (1965). A platform with 6 degrees of freedom.Proceedings of the Institution of Mechanical Engineers, Part 1, vol. 15, pp. 371–386.Valera, A., Benimeli, F., Solaz, J., De Rosario, H., Robertsson, A., Nilsson, K., … Mellado, M. (2011). A Car-Seat Example of Automated Anthropomorphic Testing of Fabrics Using Force-Controlled Robot Motions. IEEE Transactions on Automation Science and Engineering, 8(2), 280-291. doi:10.1109/tase.2010.2079931Vallés, M., Díaz-Rodríguez, M., Valera, Á., Mata, V., & Page, Á. (2012). Mechatronic Development and Dynamic Control of a 3-DOF Parallel Manipulator. 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Model of Soft Tissue Artifact Propagation to Joint Angles in Human Movement Analysis

[EN] This work describes the kinematic laws that govern the transmission of soft tissue artifact errors to kinematic variables in the analysis of human movements. Artifacts are described as relative translations and rotations of the marker cluster over the bone, and a set of explicit expressions is defined to account for the effect of that relative motion on different representations of rotations: the rotation around the screw axis, or rotation vector, and three Euler angle sequences (XY0Z, YX0Y00, ZX0 Y00). Although the error transmission is nonlinear in all cases, the effect of artifacts is greater on Euler sequences than on the rotation vector. Specifically, there are crosstalk effects in Euler sequences that amplify the errors near singular configurations. This fact is an additional source of variability in studies that describe artifacts by comparing the Euler angles obtained from skin markers, with the angles of an artifact-free gold standard. The transmission of errors to rotation vector coordinates is less variable or dependent on the type of motion. This model has been tested in an experiment with a deformable mechanical model with a spherical joint.This work has been funded by the Spanish Government and co-financed by EU FEDER funds (Grants DPI2009-13830-C02-01 and DPI2009-13830-C02-02).Page Del Pozo, AF.; De Rosario Martínez, H.; Mata Amela, V.; Besa Gonzálvez, AJ. (2014). Model of Soft Tissue Artifact Propagation to Joint Angles in Human Movement Analysis. Journal of Biomechanical Engineering. 136:1-7. doi:10.1115/1.4026226S1713

Representation of planar motion of complex joints by means of rolling pairs. Application to neck motion

[EN] We propose to model planar movements between two human segments by means of rolling-without-slipping kinematic pairs. We compute the path traced by the instantaneous center of rotation (ICR) as seen from the proximal and distal segments, thus obtaining the fixed and moving centrodes, respectively. The joint motion is then represented by the rolling-without-slipping of one centrode on the other. The resulting joint kinematic model is based on the real movement and accounts for nonfixed axes of rotation; therefore it could improve current models based on revolute pairs in those cases where joint movement implies displacement of the ICR. Previous authors have used the ICR to characterize human joint motion, but they only considered the fixed centrode. Such an approach is not adequate for reproducing motion because the fixed centrode by itself does not convey information about body position. The combination of the fixed and moving centrodes gathers the kinematic information needed to reproduce the position and velocities of moving bodies. To illustrate our method, we applied it to the flexion-extension movement of the head relative to the thorax. The model provides a good estimation of motion both for position variables (mean R pos=0.995) and for velocities (mean R vel=0.958). This approach is more realistic than other models of neck motion based on revolute pairs, such as the dual-pivot model. The geometry of the centrodes can provide some information about the nature of the movement. For instance, the ascending and descending curves of the fixed centrode suggest a sequential movement of the cervical vertebrae. © 2010 Elsevier Ltd.This work was funded by the Spanish Government and co-financed by EU FEDER funds (Grants DPI2006-14722-C02-01, DPI2006-14722-C02-02, DPI2009-13830-C02-01, DPI2009-13830-C02-02 and Ramon y Cajal contract to JAG).Page Del Pozo, AF.; De Rosario Martínez, H.; Galvez Griso, JA.; Mata Amela, V. (2011). Representation of planar motion of complex joints by means of rolling pairs. Application to neck motion. Journal of Biomechanics. 44(4):747-750. https://doi.org/10.1016/j.jbiomech.2010.11.019S74775044

Vision-Based Hybrid Controller to Release a 4-DOF Parallel Robot from a Type II Singularity

[EN] The high accuracy and dynamic performance of parallel robots (PRs) make them suitable to ensure safe operation in human¿robot interaction. However, these advantages come at the expense of a reduced workspace and the possible appearance of type II singularities. The latter is due to the loss of control of the PR and requires further analysis to keep the stiffness of the PR even after a singular configuration is reached. All or a subset of the limbs could be responsible for a type II singularity, and they can be detected by using the angle between two output twist screws (OTSs). However, this angle has not been applied in control because it requires an accurate measure of the pose of the PR. This paper proposes a new hybrid controller to release a 4-DOF PR from a type II singularity based on a real time vision system. The vision system data are used to automatically readapt the configuration of the PR by moving the limbs identified by the angle between two OTSs. This controller is intended for a knee rehabilitation PR, and the results show how this release is accomplished with smooth controlled movements where the patient¿s safety is not compromised.This research was funded by the FEDER-CICYT project with reference PID2020-119522RBI00 (ROBOTS PARALELOS DE REHABILITACION: DETECCION Y CONTROL DE SINGULARIDADES EN PRESENCIA DE ERRORES DE MANUFACTURA), Spain.Pulloquinga-Zapata, J.; Escarabajal-Sánchez, RJ.; Ferrándiz, J.; Vallés Miquel, M.; Mata Amela, V.; Urízar, M. (2021). Vision-Based Hybrid Controller to Release a 4-DOF Parallel Robot from a Type II Singularity. Sensors. 21(12):1-21. https://doi.org/10.3390/s21124080121211

Kinematic description of soft tissue artifacts: quantifying rigid versus deformation components and their relation with bone motion

[EN] This paper proposes a kinematic approach for describing soft tissue artifacts (STA) in human movement analysis. Artifacts are represented as the field of relative displacements of markers with respect to the bone. This field has two components: deformation component (symmetric field) and rigid motion (skew-symmetric field). Only the skew-symmetric component propagates as an error to the joint variables, whereas the deformation component is filtered in the kinematic analysis process. Finally, a simple technique is proposed for analyzing the sources of variability to determine which part of the artifact may be modeled as an effect of the motion, and which part is due to other sources. This method has been applied to the analysis of the shank movement induced by vertical vibration in 10 subjects. The results show that the cluster deformation is very small with respect to the rigid component. Moreover, both components show a strong relationship with the movement of the tibia. These results suggest that artifacts can be modeled effectively as a systematic relative rigid movement of the marker cluster with respect to the underlying bone. This may be useful for assessing the potential effectiveness of the usual strategies for compensating for STA. © 2012 International Federation for Medical and Biological Engineering.This work has been funded by the Spanish Government and co-financed by EU FEDER funds (Grants DPI2009-13830-C02-01, DPI2009-13830-C02-02 and IMPIVA IMDEEA/2012/79 and IMDEEA/2012/80).De Rosario Martínez, H.; Page Del Pozo, AF.; Besa Gonzálvez, AJ.; Mata Amela, V.; Conejero Navarro, E. (2012). Kinematic description of soft tissue artifacts: quantifying rigid versus deformation components and their relation with bone motion. Medical & Biological Engineering & Computing. 50(11):1173-1181. https://doi.org/10.1007/s11517-012-0978-5S117311815011Akbarshahi M, Schache AG, Fernandez JW, Baker R, Banks S, Pandy MG (2010) Non-invasive assessment of soft-tissue artifact and its effect on knee joint kinematics during functional activity. J Biomech 43:1292–1301Alexander EJ, Andriacchi TP (2001) Correcting for deformation in skin-based marker systems. J Biomech 34:355–361Andersen MS, Benoit DL, Damsgaard M, Ramsey DK, Rasmussen J (2010) Do kinematic models reduce the effects of soft tissue artefacts in skin marker-based motion analysis? An in vivo study of knee kinematics. J Biomech 43:268–273Andriacchi TP, Alexander EJ, Toney MK, Dyrby C, Sum J (1998) A point cluster method for in vivo motion analysis: applied to a study of knee kinematics. 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Propagation of Artifact Errors on Kinematic Variables. Effect on Euler Angles

This work has been funded by the Spanish Government and co-financed by EU FEDER funds (Grants DPI2009-13830-C02-01, DPI2009-13830- C02-02 and IMPIVA IMIDIC/2010/84)De Rosario Martínez, H.; Page Del Pozo, AF.; Mata Amela, V.; Besa Gonzálvez, AJ.; Moreno Cano, R. (2012). PROPAGATION OF ARTIFACT ERRORS ON KINEMATIC VARIABLES. EFFECT ON EULER ANGLES. Journal of Biomechanics. 45:293-293. doi:10.1016/S0021-9290(12)70294-4S2932934

Identification of Inertial Parameters for Position and Force Control of Surgical Assistance Robots

[EN] Surgeries or rehabilitation exercises are hazardous tasks for a mechanical system, as the device has to interact with parts of the human body without the hands-on experience that the surgeon or physiotherapist acquires over time. For various gynecological laparoscopic surgeries, such as laparoscopic hysterectomy or laparoscopic pelvic endometriosis, Uterine Manipulators are used. These medical devices allow the uterus to be suitably mobilized. A gap needs to be filled in terms of the precise handling of this type of devices. In this sense, this manuscript first describes the mathematical procedure to identify the inertial parameters of uterine manipulators. These parameters are needed to establish an accurate position and force control for an electromechanical system to assist surgical operations. The method for identifying the mass and the center of mass of the manipulator is based on the solution of the equations for the static equilibrium of rigid solids. Based on the manipulator inertial parameter estimation, the paper shows how the force exerted by the manipulator can be obtained. For this purpose, it solves a matrix system composed of the torques and forces of the manipulator. Different manipulators have been used, and it has been verified that the mathematical procedures proposed in this work allow us to calculate in an accurate and efficient way the force exerted by these manipulators.The authors wish to thank the "Agencia Valenciana de la Innovacio" (Generalitat Valenciana) for the partial funding of this study under the project with reference INNCON00/20/002. We also want to thank the "Instituto Universitario de Automatica e Informatica Industrial (ai2)" of the "Universitat Politecnica de Valencia" for its financial support under the program "Plan de ayudas a la I+D+I del Instituto ai2".Zamora-Ortiz, P.; Carral-Alvaro, J.; Valera Fernández, Á.; Pulloquinga-Zapata, J.; Escarabajal-Sánchez, RJ.; Mata Amela, V. (2021). Identification of Inertial Parameters for Position and Force Control of Surgical Assistance Robots. Mathematics. 9(7):1-16. https://doi.org/10.3390/math9070773S1169