Academic literature on the topic 'Knee joint line convergence angle'
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Journal articles on the topic "Knee joint line convergence angle"
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Chun, Dong-Il, Jahyung Kim, Sung Hun Won, Jaeho Cho, Jeongku Ha, Minkyu Kil, and Young Yi. "Changes in Coronal Alignment of the Knee Joint after Supramalleolar Osteotomy." BioMed Research International 2021 (February 19, 2021): 1–8. http://dx.doi.org/10.1155/2021/6664279.
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Background. Assessing knee joint orientation changes after SMO may help clinical advancement in managing patients with ipsilateral ankle and knee joint arthritis. However, knee joint changes after supramalleolar osteotomy (SMO) have not been reported. We investigated changes in coronal alignment of the knee joint after SMO. Methods. In this multicentre study, from January 2014 to December 2018, 47 ankles with varus osteoarthritis treated with SMO were retrospectively identified. Ankle joint changes were assessed using the tibiotalar angle, talar tilt angle, and lateral distal tibial angle (LDTA); knee joint changes using the medial proximal tibial angle (MPTA), medial and lateral joint space widths (mJSW and lJSW, respectively), and medial and lateral joint line convergence angles (JLCA); and lower limb alignment changes using mechanical axis deviation angle (MADA) and the hip-knee-ankle (HKA) angle measured on full-length anteroposterior radiographs of the lower extremity. Correlation analysis and binary logistic regression analysis were performed. Results. Postoperatively, LDTA ( p < 0.001 ) and tibiotalar angle ( p < 0.001 ) significantly changed, indicating meaningful improvement in the ankle joint varus deformity. Regarding the knee joint changes, JLCA significantly changed into valgus direction ( p = 0.044 ). As for lower limb alignment changes, MADA significantly decreased ( p < 0.001 ), whereas the HKA angle significantly increased ( p < 0.001 ). In univariate and multivariate logistic regression analyses, changes in the MADA ( p < 0.001 ) and the HKA angle ( p < 0.001 ) were significantly correlated with the correction angle. Conclusions. SMO remarkably improves ankle joint varus deformity, followed by significant lower limb alignment changes. Despite meaningful changes in JLCA, the relationship between the amount of osteotomy near the ankle joint and improvement in knee joint radiographic parameters was not significant. Radiographic parameters of the knee joint would less likely be changed following SMO.
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Park, Jun-Gu, Seong-Il Bin, Jong-Min Kim, and Bum-Sik Lee. "Using the Lower Limb Adduction Angle to Predict Postoperative Knee Joint-Line Obliquity After Open-Wedge High Tibial Osteotomy." Orthopaedic Journal of Sports Medicine 9, no. 5 (May 1, 2021): 232596712110039. http://dx.doi.org/10.1177/23259671211003991.
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Background: Knee joint-line orientation is altered after open-wedge high tibial osteotomy (OWHTO), and excessive joint-line obliquity (JLO) can adversely affect outcomes. Little is known regarding preoperative prediction of postoperative knee JLO. Purpose/Hypothesis: The purpose of this study was to assess the correlation between the amount of lower limb adduction and changes in knee JLO after OWHTO. The hypothesis was that postoperative knee JLO could be predicted using the amount of lower limb adduction after OWHTO. Study Design: Case series; Level of evidence, 4. Methods: The records of 67 patients (77 knees) who underwent OWHTO for medial compartment osteoarthritis were retrospectively reviewed. The mechanical hip-knee-ankle (HKA) axis, lateral distal femoral angle, medial proximal tibial angle (MPTA), knee JLO, ankle JLO, and joint-line convergence angle were measured on standing whole-leg plain radiographs preoperatively and at 1 year postoperatively. The limb adduction angle was defined as the angle between the native weightbearing line (WBL) and the planned WBL on preoperative standing whole-leg plain radiographs. The predicted knee JLO was calculated as the sum of the preoperative knee JLO and the limb adduction angle. Multivariable linear regression analysis was used to identify the preoperative radiologic factors associated with the postoperative knee JLO. The agreement between postoperative and predicted values was determined using intraclass correlation coefficients (ICCs). Results: The estimated limb adduction angle was 4.2° ± 1.3°, and the predicted knee JLO was 4.9° ± 3.0°. The actual postoperative knee JLO was 4.5° ± 2.4°, which was a significant increase from 0.7° ± 2.4° preoperatively ( P < .001). Excellent agreement was found between the predicted knee JLO and postoperative knee JLO (ICC = 0.928; P < .001). Limb adduction angle and changes in preoperative MPTA were significantly associated with changes in knee JLO ( P < .001). On multivariable linear regression analysis, preoperative knee JLO and limb adduction angle were significantly associated with postoperative knee JLO ( P < .001; R 2 = 0.83). Conclusion: Changes in knee JLO after OWHTO were associated with adduction of the lower limb after OWHTO. During preoperative planning, postoperative knee JLO can be predicted as the sum of the preoperative knee JLO and the limb adduction angle between the preoperative WBL and planned WBL.
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Lee, Sung-Sahn, Young Keun Lee, Il Su Kim, Dong Jin Ryu, Eui Yub Jung, Do Kyung Lee, and Joon Ho Wang. "Preoperative Medial Tightness and Narrow Medial Joint Space Are Predictive Factors for Lower Extremity Alignment Change Toward Varus After Opening-Wedge High Tibial Osteotomy." Orthopaedic Journal of Sports Medicine 10, no. 8 (August 1, 2022): 232596712211191. http://dx.doi.org/10.1177/23259671221119152.
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Background: Time-dependent changes in lower extremity alignment after an opening-wedge high tibial osteotomy (OWHTO) have been poorly investigated. Moreover, few studies have investigated risk factors of postoperative alignment change. Purposes: To investigate time-dependent alignment changes and identify predictive factors for postoperative alignment change after OWHTO. Study Design: Case-control study; Level of evidence, 3. Methods: This study included patients who underwent OWHTO between March 2010 and September 2018. A total of 142 knees with a mean follow-up of 42 months were included and classified as the change group when the amount of hip-knee-ankle (HKA) angle change was >1°; if otherwise, then as the no-change group. HKA angle was obtained at 6 time points: preoperatively and at 3 months, 6 months, 1 year, 2 years, and final follow-up postoperatively. Multiple regression analysis was performed to identify the factors that were correlated with the changes in the HKA angle from 3 months to the final follow-up. Results: Among the 142 knees, 59 (42%) were included in the change group. The overall postoperative HKA angles progressed serially toward varus after OWHTO. The mean angles of the 6 time points were 8.5°, –3.7°, –3.6°, –3.3°, –3.1°, and –2.7°, respectively. The mean HKA angles of the change and no-change groups were 9.1°, –4.3°, –3.4°, –2.8°, –2.0°, and –1.4° and 8.1°, –3.3°, –3.8°, –3.6°, –3.8°, and –3.7°, respectively. Greater change in the HKA angle was predicted by preoperatively greater valgus stress joint line convergence angles and less medial joint space width. Conclusion: Of the cases of OWHTO, 42% showed correction loss of >1° at a mean follow-up of 42 months. The overall postoperative HKA angles progressed serially to varus angles after OWHTO. Preoperative greater valgus stress joint line convergence angles and less medial joint space width were predictive factors for greater change in alignment toward varus after OWHTO.
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Fürmetz, Julian, Jan Sass, Jalil Jalali, Nikolaus Degen, Wolfgang Böcker, and Peter Thaller. "3D-ANALYSIS OF LOWER LIMB ANATOMY: NORMAL VALUES FOR JOINT ANGLES AND ALIGNMENT." Orthopaedic Journal of Sports Medicine 8, no. 5_suppl4 (May 1, 2020): 2325967120S0029. http://dx.doi.org/10.1177/2325967120s00295.
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Aims and Objectives: The analysis of lower limb anatomy is mandatory in deformity surgery and total knee replacement. Standard values for joint angles and alignment are only available for 2D images using long standing and lateral radiographs. In contrast, 3D bone models realistically represent the anatomy and are independent of position and projection. Using a self-developed, standardised and validated protocol for 3D analysis of lower limb geometry, standard values for specific joint angles and axes can be obtained in a young cohort for the first time. Materials and Methods: After power and sample size analysis, 60 thin-slice CTs of the entire leg were analysed (30 patients, 13 f, 17 m; age = 33.8 [18-50 years]). After segmentation all 24 relevant bony landmarks were set using our standardised analysis method. Results of joint angles and mechanical axis deviation are calculated automatically. Mean values are stated with standard deviations to describe a possible reference range. Results: The mean neck-shaft angle (NSA) was 133±10° and the mean medial proximal femoral angle (MPFA) 85±9°. Around the knee joint, the mean mechanical lateral distal femoral angle (mLDFA) was 87±4° and the medial proximal tibial angle (MPTA) 88±5°. Medial and lateral slope averaged 12±7° and 9±8°. The deviation of the frontal mechanical leg axis from the knee joint center (MAD frontal) was 7±15mm and the mechanical femoro-tibial angle (HKA) 175±6°. Women showed a smaller mLDFA than men (86.4° vs. 87.8°, p<0.05) and a larger joint line convergence angle (JLCA 2.5° vs. 1.4°, p<0.01) representing a more valgiform anatomy. Conclusion: The standardised 3D analysis enabled reference ranges for the relevant joint angles and axes to be defined on the 3D bone model for the first time. The results redefine reference ranges for 3D measurements similar to existing 2D measurements on long standing radiographs. The systematic analysis of the complex 3D anatomy results in a multitude of new questions and possibilities in preoperative planning.
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Shin, Kyun-Ho, Sang-Bum Kim, Ki-Mo Jang, Chul-Soo Lee, and Seung-Beom Han. "Posterior tibial slope is a modifiable predictor of relatively large extension gaps in total knee arthroplasty for degenerative osteoarthritis." Journal of Orthopaedic Surgery 29, no. 1 (January 1, 2021): 230949902110020. http://dx.doi.org/10.1177/23094990211002004.
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Background: During total knee arthroplasty (TKA) for osteoarthritis, the sagittal gap imbalance (SGI) with a relatively large extension gap is an important surgical challenge. We determined the predictors of SGI with a relatively large extension gap and evaluated the surgical outcomes of knees with SGI. Methods: 551 consecutive cases of primary TKA for osteoarthritis were retrospectively reviewed. The cohort was divided into two groups according to the SGI and statistically matched according to baseline characteristics via the inverse probability of treatment weighting method. Multiple linear and logistic regression analyses were performed to determine the predictors of sagittal gap difference (SGD) and SGI. Intergroup differences in clinical and radiological outcomes were analyzed. Results: Of all the knees included, 8.5% (n = 45) presented with SGI with a relatively large extension gap and required femoral sagittal balancing to manage SGI. The hyperextension angle (HA), preoperative joint line convergence angle (JLCA), and the change in posterior tibial slope (PTS) significantly correlated to SGD and predicted SGI with a relatively large extension gap. SGI group showed significant changes in femoral posterior condylar offset and joint line height compared to those without SGI (1.48 vs −0.45, 1.37 vs −0.51, respectively). Postoperative ROM and knee society knee scores were lower in SGI group. Conclusion: Knees requiring sagittal balancing to manage SGI with a relatively large extension gap is not uncommon in TKA for osteoarthritic knees. The change in PTS is an independent and modifiable predictor of SGI.
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Kubota, Mitsuaki, Youngji Kim, Taisuke Sato, Junichiro Yamaguchi, Ryuichi Ohno, Kazuo Kaneko, and Muneaki Ishijima. "The actual knee function was not influenced by joint line obliquity after open-wedge high tibial osteotomy." SICOT-J 6 (2020): 4. http://dx.doi.org/10.1051/sicotj/2020001.
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Purpose: Excessive joint line obliquity (JLO) after open-wedge high tibial osteotomy (OWHTO) induces detrimental stress on the articular cartilage. The purpose of this article is to assess the correlation between JLO and the clinical results after OWHTO. Methods: 68 patients were followed up for more than 1 year. JLO was assessed using a long-leg standing anteroposterior radiograph. The knee osteoarthritis outcome score (KOOS) and KSS (Knee Society score) objective knee score were assessed as clinical scores. The Weight-bearing line ratio (WBLR), medial proximal tibial angle (MPTA), lateral distal femoral angle (LDFA), and joint line convergence angle (JLCA) were assessed as radiological parameters. The timed up-and-go (TUG) test and single-leg standing (SLS) test were performed, and the isometric muscle strength of the quadriceps and hamstrings was assessed to evaluate the knee function. The primary outcomes were the correlations between the JLO and the clinical score, radiological parameters and knee function after OWHTO. The secondary objective of this study was to detect the factor with the greatest influence on JLO. Results: There were significant correlations between the postoperative JLO and the KOOS in the subcategories of pain, activities of daily living (ADL), and sports and recreation (r = −0.311, −0.302, −0.282, p = 0.011, 0.014, 0.022, respectively). However, the postoperative JLO was not significantly correlated with the KSS, knee function, or muscle strength. The preoperative LDFA and postoperative MPTA were factors influencing increased JLO after OWHTO. Discussion: There was no significant correlation between the JLO and the actual knee function. The preoperative LDFA and postoperative MPTA were factors that influenced the increase in JLO after OWHTO.
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Xu, Xinghui, Jin Yang, Jun Li, Deping Yao, Pan Deng, Boliang Chen, and Yifei Liu. "Relationship between the height of fibular head and the incidence and severity of knee osteoarthritis." Open Medicine 17, no. 1 (January 1, 2022): 1330–37. http://dx.doi.org/10.1515/med-2022-0523.
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Abstract The purpose of this study was to investigate the correlation between fibular head height and the incidence and severity of osteoarthritis associated with varus knee deformity. The fibular head height, joint line convergence angle (JLCA) and medial proximal tibial angle (MPTA) were measured in a three-dimensional model. Ordinal multivariate logistic regression was used to analyze the correlation between fibular head height and Kellgren–Lawrence (K–L) grade. Pearson correlation was used to analyze the correlation between fibular head height and K–L grade. A total of 232 patients (232 knees) were finally included in the study. There were significant differences in JLCA and hip–knee–ankle angle (P < 0.05), and both JLCA and hip–knee–ankle angle increased with severe aggravation of K–L grade. Both fibular head height and MPTA decreased as the K–L grade was severely aggravated. There was a significant negative correlation between K–L grade and fibular head height (r = −0.812, P < 0.001). Furthermore, there was a significant negative correlation between fibular head height and hip–knee–ankle angle (r = −0.7905, P < 0.001). In addition to body mass index, fibular head height is a risk factor for the pathogenesis of osteoarthritis associated with varus knee deformity; the smaller the fibular head height, the more severe the degree of varus deformity.
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Harrer, Jörg, Max Schenke, Christoph Lutter, Jörg Dickschas, Matthias Feucht, and Thomas Tischer. "Double-Level Osteotomy in Severe Varus Malalignment to Optimize Knee Joint Restoration." Video Journal of Sports Medicine 1, no. 6 (November 2021): 263502542110466. http://dx.doi.org/10.1177/26350254211046632.
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Background: Lower extremity alignment-correcting procedures for unicompartmental osteoarthritis are experiencing a rapid rise. Medial open-wedge high tibial osteotomy (MOW-HTO) thereby represents the most common technique among osteotomies but is limited in cases of severe malalignment. Some cases make a double-level osteotomy necessary. Indications: If planning of malalignment correction using a MOW-HTO results in a mechanical medial proximal tibial angle (mMPTA) of more than 93° (causing an oblique joint line), double-level osteotomy is indicated to avoid nonphysiological knee kinematics. Technique Description: After clinical examination and detailed analysis of malalignment (full-weight-bearing long-leg radiograph: hip-knee-angle [HKA], mMPTA, mechanical lateral distal femoral angle [mLDFA], joint line convergence angle [JLCA]), as well as individualized planning of the correction, the surgical procedure starts with an arthroscopy to evaluate the cartilage conditions and eventually treat intraarticular pathologies. Then, the femoral supracondylar correction is performed (closed wedge, biplanar osteotomy [ to increase bony healing]) according to the presurgical planning by resecting the osteotomy wedge with the measured length. K-wires are placed to check the correction. An angle-stable plate is used for osteosynthesis. The wedge taken out will be used as bone stock for the MOW-HTO afterward. The biplanar open-wedge tibial osteotomy is then performed subsequently using a medial tibial approach and an angle-stable plate. Opening of the osteotomy is then performed and double checked with intraoperative fluoroscopy using an alignment rod. Postoperative partial weight bearing for 6 weeks is recommended. Results: In recent literature, only few publications report on results of double-level osteotomies. Babis et al reports that it is a valuable procedure for patients with large varus deformity. Nakayama et al noted a significant improvement in patient-registered clinical outcomes in early postoperative evaluation of 20 patients. Schröter et al reports on 37 knees and findings include good clinical results, despite progressive osteoarthritis. Discussion/Conclusion: In cases of severe malalignment, adequate axis correction may require a double-level osteotomy. Exact preoperative planning is essential. Results reported in recent publications are promising. By splitting 1 large correction into 2 smaller ones, complications like hinge fracture and delayed bone healing are lowered.
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McEwen, P., G. Balendra, and K. Doma. "Medial and lateral gap laxity differential in computer-assisted kinematic total knee arthroplasty." Bone & Joint Journal 101-B, no. 3 (March 2019): 331–39. http://dx.doi.org/10.1302/0301-620x.101b3.bjj-2018-0544.r1.
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AimsThe results of kinematic total knee arthroplasty (KTKA) have been reported in terms of limb and component alignment parameters but not in terms of gap laxities and differentials. In kinematic alignment (KA), balance should reflect the asymmetrical balance of the normal knee, not the classic rectangular flexion and extension gaps sought with gap-balanced mechanical axis total knee arthroplasty (MATKA). This paper aims to address the following questions: 1) what factors determine coronal joint congruence as measured on standing radiographs?; 2) is flexion gap asymmetry produced with KA?; 3) does lateral flexion gap laxity affect outcomes?; 4) is lateral flexion gap laxity associated with lateral extension gap laxity?; and 5) can consistent ligament balance be produced without releases?Patients and MethodsA total of 192 KTKAs completed by a single surgeon using a computer-assisted technique were followed for a mean of 3.5 years (2 to 5). There were 116 male patients (60%) and 76 female patients (40%) with a mean age of 65 years (48 to 88). Outcome measures included intraoperative gap laxity measurements and component positions, as well as joint angles from postoperative three-foot standing radiographs. Patient-reported outcome measures (PROMs) were analyzed in terms of alignment and balance: EuroQol (EQ)-5D visual analogue scale (VAS), Knee Injury and Osteoarthritis Outcome Score (KOOS), KOOS Joint Replacement (JR), and Oxford Knee Score (OKS).ResultsPostoperative limb alignment did not affect outcomes. The standing hip-knee-ankle (HKA) angle was the sole positive predictor of the joint line convergence angle (JLCA) (p < 0.001). Increasing lateral flexion gap laxity was consistently associated with better outcomes. Lateral flexion gap laxity did not correlate with HKA angle, the JLCA, or lateral extension gap laxity. Minor releases were required in one third of cases.ConclusionThe standing HKA angle is the primary determinant of the JLCA in KTKA. A rectangular flexion gap is produced in only 11% of cases. Lateral flexion gap laxity is consistently associated with better outcomes and does not affect balance in extension. Minor releases are sometimes required as well, particularly in limbs with larger preoperative deformities. Cite this article: Bone Joint J 2019;101-B:331–339.
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Choi, Han Gyeol, Joo Sung Kim, Hyun Jin Yoo, You Sun Jung, and Yong Seuk Lee. "The Fate of Bone Marrow Lesions After Open Wedge High Tibial Osteotomy: A Comparison Between Knees With Primary Osteoarthritis and Subchondral Insufficiency Fractures." American Journal of Sports Medicine 49, no. 6 (April 1, 2021): 1551–60. http://dx.doi.org/10.1177/03635465211002160.
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Background: Subchondral insufficiency fracture of the knee (SIFK) is characterized by a subchondral lesion that may lead to end-stage osteoarthritis (OA). In patients who have SIFK in a precollapse state with varus malalignment, a joint-preserving technique such as open wedge high tibial osteotomy (OWHTO) should be considered. Purpose: To evaluate the efficacy of OWHTO in primary OA and SIFK-dominant OA by clinical and radiological evaluations including magnetic resonance imaging (MRI). Study Design: Cohort study; Level of evidence 3. Methods: A total of 33 SIFK-dominant OA knees and 66 with primary OA that underwent biplanar OWHTO between March 2014 and February 2016 were included after 1:2 propensity score matching. The MRI Osteoarthritis Knee Score was used to assess bone marrow lesions (BMLs) preoperatively and at follow-up. The weightbearing line ratio, the hip-knee-ankle angle, and the joint line convergence angle were measured. The clinical outcomes assessed were range of motion, the American Knee Society Score, and the Western Ontario and McMaster University (WOMAC) score. Results: The mean follow-up period was 41.2 ± 12.6 months. The distribution of preoperative BML grade in the SIFK-dominant OA group was significantly higher in both the femur and tibia ( P < .001 and <.001, respectively) than that in the primary OA group. However, the difference was not significant postoperatively (femur, P = .425; tibia, P = .462). In both groups, postoperative BMLs showed significant improvement compared with preoperative BMLs (primary OA [femur, P < .001; tibia, P = .001] and SIFK-dominant OA [femur, P < .001; tibia, P < .001]). The WOMAC pain score was higher in the SIFK-dominant OA group preoperatively (primary OA, 7.0 ± 3.73; SIFK-dominant OA, 9.17 ± 2.6; P = .032) even though it was not different at the final follow-up (primary OA, 2.11 ± 1.7; SIFK-dominant OA, 1.79 ± 1.32; P = .179). Conclusion: OWHTO is an effective procedure not only for primary OA but also for SIFK-dominant OA. OWHTO can improve BMLs, which represent the main pathological feature of SIFK. Therefore, in patients who have SIFK with varus malalignment, OWHTO can be an attractive treatment option for preserving the joint and enhancing subchondral bone healing.
Conference papers on the topic "Knee joint line convergence angle"
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Kumar, Amit, Anoop Kant Godiyal, and Deepak Joshi. "Force Myography based Continuous Estimation of Knee Joint Angle using Artificial Neural Network." In 2019 IEEE 5th International Conference for Convergence in Technology (I2CT). IEEE, 2019. http://dx.doi.org/10.1109/i2ct45611.2019.9033934.
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Gokhale, S. "relationship of the change in varus and knee joint line inclination angle with the outcome of Oxford partial knee replacement in India." In Deutscher Kongress für Orthopädie und Unfallchirurgie. Georg Thieme Verlag KG, 2020. http://dx.doi.org/10.1055/s-0040-1717230.
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De Faria, Daniela Vacarini, Marcos Máximo, and Luiz Góes. "Requirement derivation method for a legged robot with series-elastic actuators." In VIII Workshop de Teses e Dissertações em Robótica/Concurso de Teses e Dissertações em Robótica. Sociedade Brasileira de Computação - SBC, 2020. http://dx.doi.org/10.5753/wtdr_ctdr.2020.14955.
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In this work we propose a new methodology for requirement derivation of the dynamical requirements of a series elastic actuator applied to a legged robot. The leg model consists of a mechanism composed of three links – representing the thigh, the shin and the foot – and two Series Elastics Actuators (SEA) – representing the knee and ankle. The stance phase of a running gait is modeled according to the Spring Loaded Inverted Pendulum (SLIP) method. To make sure that sufficient extent of running patterns is covered, the SLIP parameters are sampled inside a predefined range using the Improved Distributed Hypercube Sampling method. The number of samples used in this study is selected through a convergence test. The leg performance is then studied through a comparison between the CoM trajectory obtained simulating the mechanism with ideal actuators on its joints and with SEAs. A closed loop Impedance Controller is used to calculate the torque required by each joint that allows the system to behave as a spring, thus mimicking the spring-like behavior of the leg during the SLIP movement. The SEAs are modeled by a parametric transfer function that is also presented in this work. To the best of our knowledge, this work is the first to propose a method that accounts for the performance of this task execution.
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Viaña Perez, Javier, Drew Scott, Manish Kumar, and Kelly Cohen. "Dynamic Genetic Algorithm for Optimizing Movement of a Six-Limb Creature." In ASME 2020 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/dscc2020-3243.
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Abstract In this study we consider a Dynamic Genetic Algorithm used to optimize the movement of a symmetric six-legged creature. The optimal movement is that which advances the creature in a straight line forward with the greatest average speed. The mutation rate and crossover rate are adjusted based on number of iterations the algorithm has completed. This dynamic element was added to improve convergence rate as well as reducing the chance that the algorithm is stuck in a local optimum. The chromosomes are represented by a 2-dimensional array, where the rows represent sequences of movement. Each row defines the change in the angle for all the joints. Angular rates are restricted per joint, as well as ranges of motion. The fitness of a chromosome is determined by the resultant average speed, calculated as total displacement of the center of gravity over total time of movements in the chromosome. The results of this study show the possibility to breed mathematically the creature by using the Dynamic Genetic Algorithm proposed. This learning process converged, for all the simulations carried out, to the natural motion of six-legged beings like the ants.