Inspired by the agility and maneuverability of running kangaroos, a prototype robot was developed using a reduced order model to constrain the system. Both passive and active models were used to understand the relationship between system parameters and gait performance. A frequency response experiment was performed on the prototype to quantify the relationship between design parameters and system responses. Additionally, preliminary tail controllers were tested. Based on the results of the initial platform, a new robot was designed and built as a platform for the study of three dimensional hopping.
{"title":"Design of a Kangaroo Inspired Hopping Robot for Unrestricted Locomotion and Controller Development","authors":"Austin Curtis, James A. Mynderse, H. Vejdani","doi":"10.1115/dscc2019-9083","DOIUrl":"https://doi.org/10.1115/dscc2019-9083","url":null,"abstract":"\u0000 Inspired by the agility and maneuverability of running kangaroos, a prototype robot was developed using a reduced order model to constrain the system. Both passive and active models were used to understand the relationship between system parameters and gait performance. A frequency response experiment was performed on the prototype to quantify the relationship between design parameters and system responses. Additionally, preliminary tail controllers were tested. Based on the results of the initial platform, a new robot was designed and built as a platform for the study of three dimensional hopping.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78570577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Demetris Coleman, Maria L. Castaño, Osama Ennasr, Xiaobo Tan
Autonomous underwater gliders have become valuable tools for a myriad of applications ranging from ocean exploration to fish tracking to environmental sampling. To be suitable for these types of applications, precise sensing and monitoring is desired, which makes accurate trajectory control important. However, highly nonlinear under-actuated dynamics present significant challenges in control of gliders. In this work a backstepping-based controller is proposed for an underwater glider to track a desired position and heading reference in the sagittal plane with only two control inputs, the buoyancy and center of gravity along the longitudinal direction. In particular,the under-actuation issue is addressed by exploiting the coupled dynamics and introducing a new modified error that combines the tracking errors of heading and position references. In addition, an auxiliary system is incorporated to account for input constraints. Finally, a sliding mode observer is designed to obtain the estimates of body-fixed velocities, to facilitate practical implementation of the designed controller. The effectiveness of the proposed control scheme is demonstrated via simulations and its advantages are shown via comparison with a PID controller.
{"title":"Backstepping-Based Trajectory Tracking for Underwater Gliders","authors":"Demetris Coleman, Maria L. Castaño, Osama Ennasr, Xiaobo Tan","doi":"10.1115/dscc2019-9028","DOIUrl":"https://doi.org/10.1115/dscc2019-9028","url":null,"abstract":"\u0000 Autonomous underwater gliders have become valuable tools for a myriad of applications ranging from ocean exploration to fish tracking to environmental sampling. To be suitable for these types of applications, precise sensing and monitoring is desired, which makes accurate trajectory control important. However, highly nonlinear under-actuated dynamics present significant challenges in control of gliders. In this work a backstepping-based controller is proposed for an underwater glider to track a desired position and heading reference in the sagittal plane with only two control inputs, the buoyancy and center of gravity along the longitudinal direction. In particular,the under-actuation issue is addressed by exploiting the coupled dynamics and introducing a new modified error that combines the tracking errors of heading and position references. In addition, an auxiliary system is incorporated to account for input constraints. Finally, a sliding mode observer is designed to obtain the estimates of body-fixed velocities, to facilitate practical implementation of the designed controller. The effectiveness of the proposed control scheme is demonstrated via simulations and its advantages are shown via comparison with a PID controller.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"103 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85838911","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Drop-on-demand (DoD) inkjet printing is used in precise-dosage deposition applications where consistent drop volume is important. Existing drop volume regulation in DoD inkjet printing are mainly open-loop approaches that are not effective in compensating for uncertainties during high volume printing applications. In this paper, a real-time image-based feedback system is proposed for regulating drop volume. A rotational symmetric model estimates drop volume from real-time images. Estimation accuracy is analyzed and validated. A simple feedback controller is developed to regulate drop volume. Experimental results validate the effectiveness of the proposed approach.
{"title":"Drop Volume Control in Drop-on-Demand Inkjet Printing","authors":"Jie Wang, Xia Chen, G. Chiu","doi":"10.1115/dscc2019-9233","DOIUrl":"https://doi.org/10.1115/dscc2019-9233","url":null,"abstract":"\u0000 Drop-on-demand (DoD) inkjet printing is used in precise-dosage deposition applications where consistent drop volume is important. Existing drop volume regulation in DoD inkjet printing are mainly open-loop approaches that are not effective in compensating for uncertainties during high volume printing applications. In this paper, a real-time image-based feedback system is proposed for regulating drop volume. A rotational symmetric model estimates drop volume from real-time images. Estimation accuracy is analyzed and validated. A simple feedback controller is developed to regulate drop volume. Experimental results validate the effectiveness of the proposed approach.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"239 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84580691","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The practice of hybridizing energy storage systems is vital to high ramp rate power applications, in which energy storage systems are constrained by strict power and energy requirements. Hybrid energy storage is typically studied in the electrical and thermal domains separately, but due to the inherent link between electrical and thermal energy domains, it is necessary to examine hybrid energy storage in both domains simultaneously. In this paper, a combined electro-thermal energy storage system is modeled and simulated. Equivalent circuit and lumped-parameter models are used to facilitate control design. PI controllers are designed for both the electrical and thermal domains to demonstrate the ability to perform multi-domain energy management.
{"title":"A Hybrid Electro-Thermal Energy Storage System for High Ramp Rate Power Applications","authors":"Cary E. Laird, A. Alleyne","doi":"10.1115/dscc2019-9089","DOIUrl":"https://doi.org/10.1115/dscc2019-9089","url":null,"abstract":"\u0000 The practice of hybridizing energy storage systems is vital to high ramp rate power applications, in which energy storage systems are constrained by strict power and energy requirements. Hybrid energy storage is typically studied in the electrical and thermal domains separately, but due to the inherent link between electrical and thermal energy domains, it is necessary to examine hybrid energy storage in both domains simultaneously. In this paper, a combined electro-thermal energy storage system is modeled and simulated. Equivalent circuit and lumped-parameter models are used to facilitate control design. PI controllers are designed for both the electrical and thermal domains to demonstrate the ability to perform multi-domain energy management.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"147 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73733358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Annika-verena Haecker, Gabriel N. Carryon, J. Tangorra, T. Sattel
The ability to change the spatial distribution of a compliant foil’s flexural rigidity can enhance the foil’s swimming performance capabilities but pose challenges to neural-based control of these types of foils. The same property that makes these foil’s effective propulsors also makes them challenging to control with a neural oscillator, namely the variation in the mechanical properties will cause the amplitude and phase of the sensory feedback signal to vary depending upon the placement of the sensor. In this study we investigate the effect of sensor placement on the entrainment characteristics of a coupled-system consisting of a neural oscillator driving a series of compliant foils with spanwise flexibility (i.e. spatially varying mechanical properties in the dorsal-ventral direction). We find that acquiring sensory feedback from the foil’s stiff region produces a broader range of frequencies over which entrainment occurs compared to acquiring feedback from the compliant region of a foil. Additionally, we characterize the thrust and lift forces generated by spanwise foils as a function of the foil’s flapping frequency and flexural rigidity.
{"title":"Neural-Based Control of Compliant Foils With Spanwise Flexibility","authors":"Annika-verena Haecker, Gabriel N. Carryon, J. Tangorra, T. Sattel","doi":"10.1115/dscc2019-9045","DOIUrl":"https://doi.org/10.1115/dscc2019-9045","url":null,"abstract":"\u0000 The ability to change the spatial distribution of a compliant foil’s flexural rigidity can enhance the foil’s swimming performance capabilities but pose challenges to neural-based control of these types of foils. The same property that makes these foil’s effective propulsors also makes them challenging to control with a neural oscillator, namely the variation in the mechanical properties will cause the amplitude and phase of the sensory feedback signal to vary depending upon the placement of the sensor. In this study we investigate the effect of sensor placement on the entrainment characteristics of a coupled-system consisting of a neural oscillator driving a series of compliant foils with spanwise flexibility (i.e. spatially varying mechanical properties in the dorsal-ventral direction). We find that acquiring sensory feedback from the foil’s stiff region produces a broader range of frequencies over which entrainment occurs compared to acquiring feedback from the compliant region of a foil. Additionally, we characterize the thrust and lift forces generated by spanwise foils as a function of the foil’s flapping frequency and flexural rigidity.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"6 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78361440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, we introduce an agent-based model of lost person behavior that may be used to improve current methods for wilderness search and rescue (SAR). The model defines agents moving on a landscape with behavior considered as a random variable. The behavior uses a distribution of four known lost person behavior strategies in order to simulate possible trajectories for the agent. We simulate all possible distributions of behaviors in the model and compute distributions of horizontal distances traveled in a fixed time. By comparing these results to analogous data from a database of lost person cases, we explore the model’s validity with respect to real-world data.
{"title":"An Agent-Based Model of Lost Person Dynamics for Enabling Wilderness Search and Rescue","authors":"Amanda Hashimoto, N. Abaid","doi":"10.1115/dscc2019-9222","DOIUrl":"https://doi.org/10.1115/dscc2019-9222","url":null,"abstract":"\u0000 In this paper, we introduce an agent-based model of lost person behavior that may be used to improve current methods for wilderness search and rescue (SAR). The model defines agents moving on a landscape with behavior considered as a random variable. The behavior uses a distribution of four known lost person behavior strategies in order to simulate possible trajectories for the agent. We simulate all possible distributions of behaviors in the model and compute distributions of horizontal distances traveled in a fixed time. By comparing these results to analogous data from a database of lost person cases, we explore the model’s validity with respect to real-world data.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"43 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83393972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Although visual feedback has enabled a wide range of robotic capabilities such as autonomous navigation and robotic surgery, low sampling rate and time delays of visual outputs continue to hinder real-time applications. When partial knowledge of the target dynamics is available, however, we show the potential of significant performance gain in vision-based target following. Specifically, we propose a new framework with Kalman filters and multirate model-based prediction (1) to reconstruct fast-sampled 3D target position and velocity data, and (2) to compensate the time delay for general robotic motion profiles. Along the path, we study the impact of modeling choices and the delay duration, build simulation tools, and experimentally verify different algorithms with a robot manipulator equipped with an eye-in-hand camera. The results show that the robot can track a moving target with fast dynamics even if the visual measurements are slow and incapable of providing timely information.
{"title":"Following Fast-Dynamic Targets With Only Slow and Delayed Visual Feedback: A Kalman Filter and Model-Based Prediction Approach","authors":"Hui Xiao, Xu Chen","doi":"10.1115/dscc2019-9022","DOIUrl":"https://doi.org/10.1115/dscc2019-9022","url":null,"abstract":"\u0000 Although visual feedback has enabled a wide range of robotic capabilities such as autonomous navigation and robotic surgery, low sampling rate and time delays of visual outputs continue to hinder real-time applications. When partial knowledge of the target dynamics is available, however, we show the potential of significant performance gain in vision-based target following. Specifically, we propose a new framework with Kalman filters and multirate model-based prediction (1) to reconstruct fast-sampled 3D target position and velocity data, and (2) to compensate the time delay for general robotic motion profiles. Along the path, we study the impact of modeling choices and the delay duration, build simulation tools, and experimentally verify different algorithms with a robot manipulator equipped with an eye-in-hand camera. The results show that the robot can track a moving target with fast dynamics even if the visual measurements are slow and incapable of providing timely information.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"42 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86846191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This article presents a novel kinematic model and controller design for a mobile robot with four Centered Orientable Conventional (COC) wheels. When compared to non-conventional wheels, COC wheels perform better over rough terrain, are not subject to vertical chatter and offer better braking capability. However, COC wheels are pseudo-omnidirectional and subject to nonholonomic constraints. Several established modeling and control techniques define and control the Instantaneous Center of Rotation (ICR); however, this method involves singular configurations that are not trivial to eliminate. The proposed method uses a novel ICR-based kinematic model to avoid these singularities, and an ICR-based nonlinear controller for one ‘master’ wheel. The other ‘slave’ wheels simply track the resulting kinematic relationships between the ‘master’ wheel and the ICR. Thus, the nonlinear control problem is reduced from 12th to 3rd-order, becoming much more tractable. Simulations with a feedback linearization controller verify the approach.
{"title":"Instantaneous Center of Rotation-Based Master-Slave Kinematic Modeling and Control","authors":"V. Ramanathan, A. Zelenak, M. Pryor","doi":"10.1115/dscc2019-9123","DOIUrl":"https://doi.org/10.1115/dscc2019-9123","url":null,"abstract":"\u0000 This article presents a novel kinematic model and controller design for a mobile robot with four Centered Orientable Conventional (COC) wheels. When compared to non-conventional wheels, COC wheels perform better over rough terrain, are not subject to vertical chatter and offer better braking capability. However, COC wheels are pseudo-omnidirectional and subject to nonholonomic constraints. Several established modeling and control techniques define and control the Instantaneous Center of Rotation (ICR); however, this method involves singular configurations that are not trivial to eliminate. The proposed method uses a novel ICR-based kinematic model to avoid these singularities, and an ICR-based nonlinear controller for one ‘master’ wheel. The other ‘slave’ wheels simply track the resulting kinematic relationships between the ‘master’ wheel and the ICR. Thus, the nonlinear control problem is reduced from 12th to 3rd-order, becoming much more tractable. Simulations with a feedback linearization controller verify the approach.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"21 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88360532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, the problem of using a limited number of mobile sensors to sense/measure a time-varying distribution of a field over a multi dimensional space is considered. As the number of sensors, in general, is not adequate for capturing the dynamic distribution with the needed spatial resolution, the sensors are required to be transited between the sampled locations, resulting in intermittent measurement at each sampled location. Therefore, it becomes challenging to use the measured data to recover/restore not only the dynamic process at each sampled/measured location, but also the dynamic distribution over the entire measured space, with high temporal and spatial resolutions. Such a multi-mobile sensing problem, however, cannot be addressed by using existing methods directly. In this work, we propose to tackle this problem through the compressed sensing framework. The randomness requirement of the compressed sensing, however, results in the temporal-spatial coupling, and the constraints in selecting the sampled locations due to the limit of the sensor speed. We propose a spatial-temporal pairing method to avoid the temporal-spatial coupling, and a checking-and-removal process to remove the sensor speed constraint. Simulation results of a video recovery example is presented and discussed to illustrate the proposed method.
{"title":"Multi-Mobile Sensing With Temporal-Spatial Coupling via Compressed Sensing","authors":"Tianwei Li, Q. Zou","doi":"10.1115/dscc2019-9218","DOIUrl":"https://doi.org/10.1115/dscc2019-9218","url":null,"abstract":"\u0000 In this paper, the problem of using a limited number of mobile sensors to sense/measure a time-varying distribution of a field over a multi dimensional space is considered. As the number of sensors, in general, is not adequate for capturing the dynamic distribution with the needed spatial resolution, the sensors are required to be transited between the sampled locations, resulting in intermittent measurement at each sampled location. Therefore, it becomes challenging to use the measured data to recover/restore not only the dynamic process at each sampled/measured location, but also the dynamic distribution over the entire measured space, with high temporal and spatial resolutions. Such a multi-mobile sensing problem, however, cannot be addressed by using existing methods directly. In this work, we propose to tackle this problem through the compressed sensing framework. The randomness requirement of the compressed sensing, however, results in the temporal-spatial coupling, and the constraints in selecting the sampled locations due to the limit of the sensor speed. We propose a spatial-temporal pairing method to avoid the temporal-spatial coupling, and a checking-and-removal process to remove the sensor speed constraint. Simulation results of a video recovery example is presented and discussed to illustrate the proposed method.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"11 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82776985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper addresses an energy-balanced leader-switching policy for formation rotation control of multi-agent systems inspired by bird flocks. Birds that flock in V-formation with a leader rotation strategy are able to travel longer distances due to reduced drag and therefore less energy expenditure. This flocking behavior with a leader rotation will result in more conservation of overall energy and will be particularly beneficial to migrating birds that should fly long distances without landing. In this paper, we propose an energy-balanced leader-switching policy inspired by this bird flocking behavior in order to increase the flight range for multi-agent systems. The formation control of multi-agent systems is achieved by the consensus algorithm, which is fully decentralized through the use of information exchanges between agents. The proposed leader-switching method is not necessarily incorporated with the consensus dynamics and thus, the leader-switching algorithm can be decoupled from formation control dynamics. Therefore, the proposed method can simplify the leader-switching algorithm, making it easy to implement. Moreover, we propose the analytic flight distance based on the energy consumption model for each agent. To test the validity of the developed method, several simulation results are presented.
{"title":"Energy-Balanced Leader-Switching Policy for Formation Rotation Control of Multi-Agent Systems Inspired by Bird Flocks","authors":"C. Dotson, Geronimo Macias, Kooktae Lee","doi":"10.1115/dscc2019-9044","DOIUrl":"https://doi.org/10.1115/dscc2019-9044","url":null,"abstract":"\u0000 This paper addresses an energy-balanced leader-switching policy for formation rotation control of multi-agent systems inspired by bird flocks. Birds that flock in V-formation with a leader rotation strategy are able to travel longer distances due to reduced drag and therefore less energy expenditure. This flocking behavior with a leader rotation will result in more conservation of overall energy and will be particularly beneficial to migrating birds that should fly long distances without landing. In this paper, we propose an energy-balanced leader-switching policy inspired by this bird flocking behavior in order to increase the flight range for multi-agent systems. The formation control of multi-agent systems is achieved by the consensus algorithm, which is fully decentralized through the use of information exchanges between agents. The proposed leader-switching method is not necessarily incorporated with the consensus dynamics and thus, the leader-switching algorithm can be decoupled from formation control dynamics. Therefore, the proposed method can simplify the leader-switching algorithm, making it easy to implement. Moreover, we propose the analytic flight distance based on the energy consumption model for each agent. To test the validity of the developed method, several simulation results are presented.","PeriodicalId":41412,"journal":{"name":"Mechatronic Systems and Control","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2019-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89134624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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