Gabriel Abba - Profile on Academia.edu (original) (raw)
Papers by Gabriel Abba
International Journal of Material Forming, 2009
In this study, an experimental setup of a forging process has been designed which allows to apply... more In this study, an experimental setup of a forging process has been designed which allows to apply vibrations to the lower die of amplitude ranging from 0 to 80 µm at frequencies varying from 1 to 130 Hz thanks to the use of a stack piezoelectric actuator fed by an electronic inverter. In order to explore those results, a coupling model has been developed to provide a design tool in a mechatronic frame which consists of an analytical model of the forging process based on simplified visco-plastic laws and a state space model of the piezoelectric actuator based on a finite element approach [1]. The coupling model can be used to analyse the important parameters of the whole process in order to optimize the forging process design using mechanical vibrations or to control the process if necessary. A finite element simulation of forging process using mechanical vibration based on finite element software Forge2008® is also presented in this study. The results obtained by experiment, finite element simulation and simulation using the model above are compared in the case of simple upsetting, with good agreement. Moreover, it can be concluded that high frequencies are not required to observe this phenomenon. Finally visco-plasticity phenomenon is not self-sufficient to explain completely the force reduction.
The paper presents a velocity hysteresis friction model. This model can be used for simulation or... more The paper presents a velocity hysteresis friction model. This model can be used for simulation or control of an accurate micropositioning servomechanism. The mechanical and friction parameters are identified from measured signals at low velocities, and with the use of a closed loop identification method. The measured signals are very noised. The number of measurement samples available is very low. The friction model depends on position, velocity and acceleration and includes the Coulomb, Stribeck and viscous frictions. A hysteresis effect integrated by an exponential term and the acceleration is added in the model. The identified parameters are validated by applying an efficient precision method based on the sensitivity analysis of nonlinear models and a normalized mean-square-error criterion.
Quasi optimal gait for a biped robot using genetic algorithm
1997 IEEE International Conference on Systems, Man, and Cybernetics. Computational Cybernetics and Simulation, 1997
Abstract The context of our research is the study of legged robots. In order to realize autonomou... more Abstract The context of our research is the study of legged robots. In order to realize autonomous legged robots, the energy consumption during a step should be minimized. The method proposed is based on the expansion in Fourier's series of the joint trajectories. ...
Influence de l'orientation de l'outil sur les forces générées en FSW
Contribution à l'étude et à la réalisation de la motorisation, de la commande et de la programmation d'un robot destiné à un atelier flexible
Comparaison des actionneurs
High Productivity Print Head for Biochip Microarrayer Based on Shape Memory Alloy Micro-Actuators
Cutting Edge Robotics 2010, 2010
Nowadays, high levels of agility, maneuverability and capability of operating in reduced visual e... more Nowadays, high levels of agility, maneuverability and capability of operating in reduced visual environments and adverse weather conditions are the new trends of helicopter design. Helicopter flight control systems should make these performance requirements achievable by improving tracking performance and disturbance rejection capability. Robustness is one of the critical issues which must be considered in the control system design for such highperformance autonomous helicopter, since any mathematical helicopter model, especially those covering large flight domains, will unavoidably have uncertainty due to the empirical representation of aerodynamic forces and moments.
The paper presents a velocity hysteresis friction model. This model can be used for simulation or... more The paper presents a velocity hysteresis friction model. This model can be used for simulation or control of an accurate micropositioning servomechanism. The mechanical and friction parameters are identified from measured signals at low velocities, and with the use of a closed loop identification method. The measured signals are very noised. The number of measurement samples available is very low. The friction model depends on position, velocity and acceleration and includes the Coulomb, Stribeck and viscous frictions. A hysteresis effect integrated by an exponential term and the acceleration is added in the model. The identified parameters are validated by applying an efficient precision method based on the sensitivity analysis of nonlinear models and a normalized mean-square-error criterion.
7th IFAC Conference on Manufacturing Modelling, Management, and Control, 2013, 2013
The paper focuses on the robust identification of geometrical and elastostatic parameters of robo... more The paper focuses on the robust identification of geometrical and elastostatic parameters of robotic manipulator. The main attention is paid to the efficiency improvement of the identification algorithm. To increase the identification accuracy, it is proposed to apply the weighted least square technique that employs a new algorithm for assigning of the weighting coefficients. The latter allows taking into account variation of the measurement system precision in different directions and throughout the robot workspace. The advantages of the proposed approach are illustrated by an application example that deals with the elasto-static calibration of industrial robot.
Ingénierie de la commande des systèmes: techniques de base
Proceedings of the 16th IFAC World Congress, 2005, 2005
Control in robotics needs more and more precise models of the mechanical parts of the structure a... more Control in robotics needs more and more precise models of the mechanical parts of the structure and specially for a complex system such as a biped robot. An important but difficult aspect of this work is the modeling of the mechanical loss due to friction in the chain of transmission from the motor to the axis. Each part losses are defined as a sum of three terms, one constant, another depending only on the speed and the last depending on the torque transmitted. The robot joint kinematic chain is modeled with three elements: the motor, the gearbox and a rotational joint at the leg. The results show a good adequacy between measurement and simulation with the proposed identification method in comparison with a classic least square identification method.
Simulation results using a robot with flexibilities for machining and welding
ABSTRACT The objective of this report is to detail the models used in simulation and the results ... more ABSTRACT The objective of this report is to detail the models used in simulation and the results obtained in simulation for both machining and FSW process.This report contains in a first part the details of modeling flexibilities of serial robots primarily through a model of localized flexibilities. The flexibilities are expressed both in Cartesian space and in the joint space and taking into account possible couplings.The second part deals with the dynamic model used in the simulator and the simulation environment. A significant work was to also model the company Kuka robot controller. Machining processes and FSW are modeled by simple models but reflecting the reality of the behavior.
An alternative explanation of forming force reduction for forming process submitted to vibration: Influence of the waveform in the viscoplastic domain
Journal of Materials Processing Technology, 2016
Micro Milling Technologies for MEMS
2007 International Conference on Perspective Technologies and Methods in MEMS Design, 2007
In this paper, a comprehensive introduction of micro milling technology, which is a novel micro-m... more In this paper, a comprehensive introduction of micro milling technology, which is a novel micro-manufacturing technology to fabricate many materials with complex 3D and high aspect ratio structure, is presented. Compared with some other micro-manufacturing technologies, micro milling has a lot of merits, such as low cost, flexibility. The machine tool, micro mills, and monitoring devices are the key technologies,
7th IFAC Conference on Manufacturing Modelling, Management, and Control, 2013, 2013
The paper focuses on the robust identification of geometrical and elastostatic parameters of robo... more The paper focuses on the robust identification of geometrical and elastostatic parameters of robotic manipulator. The main attention is paid to the efficiency improvement of the identification algorithm. To increase the identification accuracy, it is proposed to apply the weighted least square technique that employs a new algorithm for assigning of the weighting coefficients. The latter allows taking into account variation of the measurement system precision in different directions and throughout the robot workspace. The advantages of the proposed approach are illustrated by an application example that deals with the elasto-static calibration of industrial robot.
Modélisation des frottements dans les éléments de transmission d'un axe de robot en vue de son identificationFriction modelling of a robot transmission chain with identification in mind
Mécanique & Industries, 2003
Control in robotics needs more and more precise models of the mechanical parts of the structure a... more Control in robotics needs more and more precise models of the mechanical parts of the structure and specially for a complex system such as a biped robot. An important but difficult aspect of this work is the modelling of the mechanical loss due to friction in the chain of ...
A Micro Milling Model Considering Metal Phases and Minimum Chip Thickness
Key Engineering Materials, 2008
Proceedings of 3rd IEEE International Conference on Image Processing, 1996
In the area of robotic vision we are interested in developing algorithms for the control of a rob... more In the area of robotic vision we are interested in developing algorithms for the control of a robot manipulator by means of visual feedback. Image analysis and exploitation of the image features are therefore steps of importance. This paper deals with the problem of three-dimensional localization of objects representing circular patterns. The first part of the paper is concerned with the parametrization of elliptic curves and a second part is dedicated to the estimation of an object's position and orientation.
International Journal of Material Forming, 2009
In this study, an experimental setup of a forging process has been designed which allows to apply... more In this study, an experimental setup of a forging process has been designed which allows to apply vibrations to the lower die of amplitude ranging from 0 to 80 µm at frequencies varying from 1 to 130 Hz thanks to the use of a stack piezoelectric actuator fed by an electronic inverter. In order to explore those results, a coupling model has been developed to provide a design tool in a mechatronic frame which consists of an analytical model of the forging process based on simplified visco-plastic laws and a state space model of the piezoelectric actuator based on a finite element approach [1]. The coupling model can be used to analyse the important parameters of the whole process in order to optimize the forging process design using mechanical vibrations or to control the process if necessary. A finite element simulation of forging process using mechanical vibration based on finite element software Forge2008® is also presented in this study. The results obtained by experiment, finite element simulation and simulation using the model above are compared in the case of simple upsetting, with good agreement. Moreover, it can be concluded that high frequencies are not required to observe this phenomenon. Finally visco-plasticity phenomenon is not self-sufficient to explain completely the force reduction.
The paper presents a velocity hysteresis friction model. This model can be used for simulation or... more The paper presents a velocity hysteresis friction model. This model can be used for simulation or control of an accurate micropositioning servomechanism. The mechanical and friction parameters are identified from measured signals at low velocities, and with the use of a closed loop identification method. The measured signals are very noised. The number of measurement samples available is very low. The friction model depends on position, velocity and acceleration and includes the Coulomb, Stribeck and viscous frictions. A hysteresis effect integrated by an exponential term and the acceleration is added in the model. The identified parameters are validated by applying an efficient precision method based on the sensitivity analysis of nonlinear models and a normalized mean-square-error criterion.
Quasi optimal gait for a biped robot using genetic algorithm
1997 IEEE International Conference on Systems, Man, and Cybernetics. Computational Cybernetics and Simulation, 1997
Abstract The context of our research is the study of legged robots. In order to realize autonomou... more Abstract The context of our research is the study of legged robots. In order to realize autonomous legged robots, the energy consumption during a step should be minimized. The method proposed is based on the expansion in Fourier's series of the joint trajectories. ...
Influence de l'orientation de l'outil sur les forces générées en FSW
Contribution à l'étude et à la réalisation de la motorisation, de la commande et de la programmation d'un robot destiné à un atelier flexible
Comparaison des actionneurs
High Productivity Print Head for Biochip Microarrayer Based on Shape Memory Alloy Micro-Actuators
Cutting Edge Robotics 2010, 2010
Nowadays, high levels of agility, maneuverability and capability of operating in reduced visual e... more Nowadays, high levels of agility, maneuverability and capability of operating in reduced visual environments and adverse weather conditions are the new trends of helicopter design. Helicopter flight control systems should make these performance requirements achievable by improving tracking performance and disturbance rejection capability. Robustness is one of the critical issues which must be considered in the control system design for such highperformance autonomous helicopter, since any mathematical helicopter model, especially those covering large flight domains, will unavoidably have uncertainty due to the empirical representation of aerodynamic forces and moments.
The paper presents a velocity hysteresis friction model. This model can be used for simulation or... more The paper presents a velocity hysteresis friction model. This model can be used for simulation or control of an accurate micropositioning servomechanism. The mechanical and friction parameters are identified from measured signals at low velocities, and with the use of a closed loop identification method. The measured signals are very noised. The number of measurement samples available is very low. The friction model depends on position, velocity and acceleration and includes the Coulomb, Stribeck and viscous frictions. A hysteresis effect integrated by an exponential term and the acceleration is added in the model. The identified parameters are validated by applying an efficient precision method based on the sensitivity analysis of nonlinear models and a normalized mean-square-error criterion.
7th IFAC Conference on Manufacturing Modelling, Management, and Control, 2013, 2013
The paper focuses on the robust identification of geometrical and elastostatic parameters of robo... more The paper focuses on the robust identification of geometrical and elastostatic parameters of robotic manipulator. The main attention is paid to the efficiency improvement of the identification algorithm. To increase the identification accuracy, it is proposed to apply the weighted least square technique that employs a new algorithm for assigning of the weighting coefficients. The latter allows taking into account variation of the measurement system precision in different directions and throughout the robot workspace. The advantages of the proposed approach are illustrated by an application example that deals with the elasto-static calibration of industrial robot.
Ingénierie de la commande des systèmes: techniques de base
Proceedings of the 16th IFAC World Congress, 2005, 2005
Control in robotics needs more and more precise models of the mechanical parts of the structure a... more Control in robotics needs more and more precise models of the mechanical parts of the structure and specially for a complex system such as a biped robot. An important but difficult aspect of this work is the modeling of the mechanical loss due to friction in the chain of transmission from the motor to the axis. Each part losses are defined as a sum of three terms, one constant, another depending only on the speed and the last depending on the torque transmitted. The robot joint kinematic chain is modeled with three elements: the motor, the gearbox and a rotational joint at the leg. The results show a good adequacy between measurement and simulation with the proposed identification method in comparison with a classic least square identification method.
Simulation results using a robot with flexibilities for machining and welding
ABSTRACT The objective of this report is to detail the models used in simulation and the results ... more ABSTRACT The objective of this report is to detail the models used in simulation and the results obtained in simulation for both machining and FSW process.This report contains in a first part the details of modeling flexibilities of serial robots primarily through a model of localized flexibilities. The flexibilities are expressed both in Cartesian space and in the joint space and taking into account possible couplings.The second part deals with the dynamic model used in the simulator and the simulation environment. A significant work was to also model the company Kuka robot controller. Machining processes and FSW are modeled by simple models but reflecting the reality of the behavior.
An alternative explanation of forming force reduction for forming process submitted to vibration: Influence of the waveform in the viscoplastic domain
Journal of Materials Processing Technology, 2016
Micro Milling Technologies for MEMS
2007 International Conference on Perspective Technologies and Methods in MEMS Design, 2007
In this paper, a comprehensive introduction of micro milling technology, which is a novel micro-m... more In this paper, a comprehensive introduction of micro milling technology, which is a novel micro-manufacturing technology to fabricate many materials with complex 3D and high aspect ratio structure, is presented. Compared with some other micro-manufacturing technologies, micro milling has a lot of merits, such as low cost, flexibility. The machine tool, micro mills, and monitoring devices are the key technologies,
7th IFAC Conference on Manufacturing Modelling, Management, and Control, 2013, 2013
The paper focuses on the robust identification of geometrical and elastostatic parameters of robo... more The paper focuses on the robust identification of geometrical and elastostatic parameters of robotic manipulator. The main attention is paid to the efficiency improvement of the identification algorithm. To increase the identification accuracy, it is proposed to apply the weighted least square technique that employs a new algorithm for assigning of the weighting coefficients. The latter allows taking into account variation of the measurement system precision in different directions and throughout the robot workspace. The advantages of the proposed approach are illustrated by an application example that deals with the elasto-static calibration of industrial robot.
Modélisation des frottements dans les éléments de transmission d'un axe de robot en vue de son identificationFriction modelling of a robot transmission chain with identification in mind
Mécanique & Industries, 2003
Control in robotics needs more and more precise models of the mechanical parts of the structure a... more Control in robotics needs more and more precise models of the mechanical parts of the structure and specially for a complex system such as a biped robot. An important but difficult aspect of this work is the modelling of the mechanical loss due to friction in the chain of ...
A Micro Milling Model Considering Metal Phases and Minimum Chip Thickness
Key Engineering Materials, 2008
Proceedings of 3rd IEEE International Conference on Image Processing, 1996
In the area of robotic vision we are interested in developing algorithms for the control of a rob... more In the area of robotic vision we are interested in developing algorithms for the control of a robot manipulator by means of visual feedback. Image analysis and exploitation of the image features are therefore steps of importance. This paper deals with the problem of three-dimensional localization of objects representing circular patterns. The first part of the paper is concerned with the parametrization of elliptic curves and a second part is dedicated to the estimation of an object's position and orientation.