Article
Acoustics
Haowen Yang, Bin Wu, Jinping Li, Yu Bao, Guoshan Xu
Summary: This paper explores the dynamics model and control methods of human running on vibrating surfaces, demonstrating the stability and effectiveness of control methods through numerical simulations and experimental tests. The impact factors of human-structure interaction are analyzed.
JOURNAL OF SOUND AND VIBRATION
(2022)
Article
Engineering, Multidisciplinary
Hao Sun, Junjie Yang, Yinghao Jia, Qinghua Li, Changhong Wang
Summary: This paper presents a novel control method for actuated-SLIP hopping on unknown terrains. By applying the hybrid averaging theorem on the SLIP non-integrable dynamics, a control Lyapunov function-based hybrid averaging controller is developed to ensure the stability of the desired gait orbit. Linear constraints on the control signal are solved through quadratic programming optimization, and the robustness against unknown disturbances is improved through online constraint adjustment.
JOURNAL OF BIONIC ENGINEERING
(2023)
Article
Robotics
Haitao Yu, Haibo Gao, Zongquan Deng
Summary: This article extends the traditional SLIP model from sagittal hopping into spatially running and proposes a novel perturbation-based approach to obtain an analytical approximate solution for the 3-D-SLIP model. The derived solution offers satisfactory prediction performance in a wide range of model parameter combinations, showcasing potential in motion planning and gait control for legged robots.
IEEE TRANSACTIONS ON ROBOTICS
(2021)
Article
Biophysics
Samuel E. Masters, John H. Challis
Summary: The study found that an additional spring-mass-damper system can increase the self-stabilizing properties of the SLIP model and enhance its resistance to perturbations, thereby improving the stability of human running.
JOURNAL OF BIOMECHANICS
(2021)
Article
Automation & Control Systems
Sicheng Xie, Xinyu Li, Liang Gao, Ling Fu, Li Jing, Weifeng Xu
Summary: This study proposes an online whole-stage gait planning method to enhance the bipedal walking performance. A new template model called Variable Spring-Loaded Inverted Pendulum with Finite-sized Foot (VSLIP-FF) model is applied, considering the role of ankles. A Finite State Machine (FSM)-based gait pattern with corresponding bio-inspired gait strategies is established. Furthermore, an online gait generator based on a neural network is applied for real-time gait planning. Experimental results demonstrate the effectiveness of the proposed method.
Article
Engineering, Multidisciplinary
Yingge Ni, Xiangyan Meng
Summary: In order to improve the energy efficiency of the hopping robot, an asymmetric spring loaded inverted pendulum hopping model with leg mass is considered. The period orbit problem of a one-legged hopping robot is investigated. Firstly, a hybrid dynamic model is constructed. Then, passive hopping gaits are found using the quasi-newton optimization method. Secondly, a PD controller is implemented to track the desired pitch trajectory of the body. By applying control during the stance phase, period orbits of the robot with offset body mass are obtained. Finally, the effect of the location of the leg mass and the body mass on hopping performances is investigated.
REVISTA INTERNACIONAL DE METODOS NUMERICOS PARA CALCULO Y DISENO EN INGENIERIA
(2023)
Article
Construction & Building Technology
Stana Zivanovic, Bintian Lin, Hiep Vu Dang, Sigong Zhang, Mladen Cosic, Colin Caprani, Qingwen Zhang
Summary: This paper critically evaluates the performance of two bipedal models with rigid legs in reproducing key features of an individual pedestrian's walking gait and representing a wide range of individuals. The results show that these models are less successful in reproducing genuine kinetic and kinematics profiles.
Article
Automation & Control Systems
Balazs A. Kovacs, Tamas Insperger
Summary: This study analyzed the critical length for stabilizability in delayed PDA feedback and predictor feedback for the inverted pendulum paradigm. It was found that the relation between the critical length and reaction delay remained quadratic in the presence of perturbations on control gains. Predictor feedback outperformed PDA feedback in terms of critical length and was more sensitive to changes in feedback delay compared to parameter uncertainties.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2022)
Article
Instruments & Instrumentation
J. Yamasaki, M. Nonaka, S. Yokota, K. Shimamura
Summary: Pendulum thrust stands are used to measure the thrust of electric propulsion systems for spacecraft. In this study, an inverted pendulum-type thrust stand with pipes and wirings as springs was developed to reduce the influence of tension. Design guidelines for spring-shaped wires were derived and a thrust stand was designed and fabricated based on these guidelines. The performance of the stand was evaluated and showed good sensitivity, low variation in measured values, and minimal thermal drift.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2023)
Article
Chemistry, Multidisciplinary
Matteo Massaro, Stefano Lovato, David J. N. Limebeer
Summary: This paper discusses a classic control problem, the erection of the inverted pendulum, specifically the minimum-time erection on a moving cart. The study reveals that the minimum-time solution may involve a singular arc and proposes a corresponding feedback control law. Furthermore, a sensitivity analysis of the solution structure is conducted by varying the model parameters, and the time-optimal solution is compared with an energy-based control strategy.
APPLIED SCIENCES-BASEL
(2022)
Article
Mathematics, Applied
Andrea Tigrini, Federica Verdini, Sandro Fioretti, Alessandro Mengarelli
Summary: In this study, extended detrended fluctuation analysis (EDFA) was applied to investigate the dynamics of human balance maintenance using an inverted pendulum (IP) model with intermittent control. The analysis focused on the changes in long-term correlation and inhomogeneity of the center of pressure (COP) time series. The results showed that the EDFA coefficients were sensitive to changes in the derivative control gain and had a correlation with the p parameter.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2022)
Article
Acoustics
Pouriya Pourgholam, Hamid Moeenfard
Summary: This study proposes a comprehensive dynamic model and a supervisory fuzzy-pole placement control strategy to achieve stable control in inverted pendulum systems. The effectiveness of the method is validated through simulation experiments, and a novel fuzzy system is introduced to improve the quality of transient response.
JOURNAL OF VIBRATION AND CONTROL
(2023)
Article
Robotics
Sungho Lee, Sungwoon Yoon, Yonghwan Jeong, Jaehong Seo, Sangshin Park, Sangchul Han, Jin Tak Kim, Jinhyeon Kim, Hyouk Ryeol Choi, Jungsan Cho
Summary: This paper proposes a multi-degrees-of-freedom two wheeled inverted pendulum robot (mD-TWIPR) for off-road transportation. The robot has a car-like structure, allowing it to transport long objects and transfer patients on off-road terrain. To overcome challenges such as limited acceleration and difficulty traversing slopes, a sliding mechanism is implemented in the mD-TWIPR, enabling it to move without tilting while carrying movable mass.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2023)
Article
Engineering, Mechanical
Yong Meng
Summary: In order to analyze the motion characteristics of the spring pendulum under the action of magnetic field force, the motion of the spring pendulum is studied by applying a uniform magnetic field in the vertical direction. First, a first-order approximate solution is given by studying the micro-vibration around its equilibrium point. An approximate solution similar to the Foucault pendulum is also presented in the case of a soft spring with strong ductility. Then, the resonance conditions of mechanical vibration are used to discover the internal resonance phenomenon of the magnetic spring pendulum, and it is concluded that the energy of the system cyclically transmits between the three modes of breathing, oscillating, and deflection. Finally, the influence of magnetic field strength on the motion stability of the spring pendulum is explored, finding not only bifurcation phenomenon at its equilibrium point but also complex dynamic behavior including chaotic motion.
NONLINEAR DYNAMICS
(2023)
Article
Acoustics
Csenge A. Molnar, Tamas Balogh, Islam Boussaada, Tamas Insperger
Summary: In this study, single and double inverted pendulum systems under delayed state feedback are analyzed for stabilizability. The critical delay for a stable closed-loop system is determined using the multiplicity-induced-dominancy property of the characteristic roots. Various methods, such as tracking D-curves with increasing delay and the Walton-Marshall method, are demonstrated for the single pendulum system.
JOURNAL OF VIBRATION AND CONTROL
(2021)
Article
Biology
Iain Hunter, Raz Leib
Summary: Natural movement is related to health, but it is difficult to measure. Existing methods cannot capture the full range of natural movement. Comparing movement across different species helps identify common biomechanical and computational principles. Developing a system to quantify movement in freely moving animals in natural environments and relating it to life quality is crucial. This study proposes a theoretical framework based on movement ability and validates it in Drosophila.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Andy Gardner
Summary: Fisher's geometric model is a useful tool for predicting key properties of Darwinian adaptation, and here it is applied to predict differences between the evolution of altruistic versus nonsocial phenotypes. The results suggest that the effect size maximizing probability of fixation is smaller in the context of altruism and larger in the context of nonsocial phenotypes, leading to lower overall probability of fixation for altruism and higher overall probability of fixation for nonsocial phenotypes.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Thomas F. Pak, Joe Pitt-Francis, Ruth E. Baker
Summary: Cell competition is a process where cells interact in multicellular organisms to determine a winner or loser status, with loser cells being eliminated through programmed cell death. The winner cells then populate the tissue. The outcome of cell competition is context-dependent, as the same cell type can win or lose depending on the competing cell type. This paper proposes a mathematical framework to study the emergence of winner or loser status, highlighting the role of active cell death and identifying the factors that drive cell competition in a cell-based modeling context.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Haruto Tomizuka, Yuuya Tachiki
Summary: Batesian mimicry is a strategy in which palatable prey species resemble unpalatable prey species to avoid predation. The evolution of this mimicry plays a crucial role in protecting the unpalatable species from extinction.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Jason W. Olejarz, Martin A. Nowak
Summary: Gene drive technology shows potential for population control, but its release may have unpredictable consequences. The study suggests that the failure of suppression is a natural outcome, and there are complex dynamics among wild populations.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Hamid Ravaee, Mohammad Hossein Manshaei, Mehran Safayani, Javad Salimi Sartakhti
Summary: Gene expression analysis is valuable for cancer classification and phenotype identification. IP3G, based on Generative Adversarial Networks, enhances gene expression data and discovers phenotypes in an unsupervised manner. By converting gene expression profiles into images and utilizing IP3G, new phenotype profiles can be generated, improving classification accuracy.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Beatrix Rahnsch, Leila Taghizadeh
Summary: This study forecasts the evolution of the COVID-19 pandemic in Germany using a network-based inference method and compares it with other approaches. The results show that the network-inference based approach outperforms other methods in short-to mid-term predictions, even with limited information about the new disease. Furthermore, predictions based on the estimation of the reproduction number in Germany can yield more reliable results with increasing data availability, but still cannot surpass the network-inference based algorithm.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Rongsheng Huang, Qiaojun Situ, Jinzhi Lei
Summary: Maintaining tissue homeostasis requires appropriate regulation of stem cell differentiation. Random inheritance of epigenetic states plays a pivotal role in stem cell differentiation. This computational model provides valuable insights into the intricate mechanism governing stem cell differentiation and cell reprogramming, offering a promising path for enhancing the field of regenerative medicine.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Patrick Vincent N. Lubenia, Eduardo R. Mendoza, Angelyn R. Lao
Summary: This study compares insulin signaling in healthy and type 2 diabetes states using reaction network analysis. The results show similarities and differences between the two conditions, providing insights into the mechanisms of insulin resistance, including the involvement of other complexes, less restrictive interplay between species, and loss of concentration robustness in GLUT4.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Nuverah Mohsin, Heiko Enderling, Renee Brady-Nicholls, Mohammad U. Zahid
Summary: Mathematical modeling is crucial in understanding radiobiology and designing treatment approaches in radiotherapy for cancer. This study compares three tumor volume dynamics models and analyzes the implications of model selection. A new metric, the point of maximum reduction of tumor volume (MRV), is introduced to quantify the impact of radiotherapy. The results emphasize the importance of caution in selecting models of response to radiotherapy due to the artifacts imposed by each model.
JOURNAL OF THEORETICAL BIOLOGY
(2024)
Article
Biology
Armindo Salvador
Summary: Michael Savageau's Biochemical Systems Analysis papers have had a significant impact on Systems Biology, generating core concepts and tools. This article provides a brief summary of these papers and discusses the most relevant developments in Biochemical Systems Theory since their publication.
JOURNAL OF THEORETICAL BIOLOGY
(2024)