I. Bonev - Academia.edu (original) (raw)

Papers by I. Bonev

Research paper thumbnail of Grafting in forestry

Research paper thumbnail of A study of work satisfaction among people, returning from peace-supporting mission

Research paper thumbnail of Academy of Sciences of the Ussr, Institute of Crystallography, Growth of Crystals (Selected Articles)

: Contents: The effect of anisotropy of properties of semiconductor crystals on segregation of im... more : Contents: The effect of anisotropy of properties of semiconductor crystals on segregation of impurities in a growing crystal; Mechanism of the oriented growth of crystalline substances (epitaxy); Deviation from Homogeneity in single crystals of gallium phosphide-gallium arsenide solid solutions grown by the epitaxial method; Some instances of change in the habit of crystals during epitaxial growth; Kinetics of the spontaneous transformation of the surface of a crystal-vapor system; and Growth and dislocation models of crystals.

Research paper thumbnail of Relationships between burn out syndrome and job satisfaction among cancer center personnel

Research paper thumbnail of Are Parallel Robots More Accurate Than Serial Robots?

Transactions of the Canadian Society for Mechanical Engineering, 2007

It is widely claimed that parallel robots are intrinsically more accurate than serial robots beca... more It is widely claimed that parallel robots are intrinsically more accurate than serial robots because their errors are averaged instead of added cumulatively, an assertion which has not been properly addressed in the literature. This paper addresses this void by comparing the kinematic accuracy of two pairs of serial-parallel 2-DOF planar robots. Only input errors are considered and all robots are optimized for accuracy, the only constraint being that they cover a given desired workspace. The results of this comparison seem to confirm that parallel robots are less sensitive to input errors than serial robots. However, this comparison is too limited to draw any general conclusions. Besides, it is virtually impossible to make a meaningful comparison between other pairs of serial and parallel robot. Therefore, there is no simple answer to this question of superiority.

Research paper thumbnail of On the terminology of the phenomena of mutual crystal orientation

Acta Crystallographica Section A, 1972

Research paper thumbnail of Anisometric growth of crystals with isometric structures

Acta Crystallographica Section A Foundations of Crystallography, 1984

GaN, a direct, wide energy gap mater~al jgap 3.5 eV/ is potentially suitable for optoelectronic d... more GaN, a direct, wide energy gap mater~al jgap 3.5 eV/ is potentially suitable for optoelectronic devices. The main reason for limited applicability are technological difficulties. The high decomposition pressure of N? leads to the thermal instability at temperatures above-900 o C under normal pressure. Another problem is a lack of good solvent for this mater~~l. The solubility of GaN in Ga at 11509C(is in order 10 % molar. Our studies of the thermodynamics of Ga-N 2 system show that the equilibrium pressure of N2 over GaN is much lower then previously predicted. Therefore the equilibrium conditions for GaN in gas pressure chamber were obtained up to 1700 o C, and the synthesis of

Research paper thumbnail of Clarification of Some Aspects of Respiration with the Help Electronic Registration of Respiratory Movements

Nauchni trudove na Visshiia meditsinski institut, Sofiia, 1964

Research paper thumbnail of Dentistry in Bulgaria

Research paper thumbnail of Numerical Computation and Avoidance of Manipulator Singularities

This thesis develops general solutions to two open problems of robot kinematics: the exhaustive c... more This thesis develops general solutions to two open problems of robot kinematics: the exhaustive computation of the singularity set of a manipulator, and the synthesis of singularity-free paths between given configurations. Obtaining proper solutions to these problems is crucial, because singularities generally pose problems to the normal operation of a robot and, thus, they should be taken into account before the actual construction of a prototype. The ability to compute the whole singularity set also provides rich information on the global motion capabilities of a manipulator. The projections onto the task and joint spaces delimit the working regions in such spaces, may inform on the various assembly modes of the manipulator, and highlight areas where control or dexterity losses can arise, among other anomalous behaviour.

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1986

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1990

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1995

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1997

Research paper thumbnail of Self motions of a special 3-(R)under-barPR planar parallel robot

Articolul prezintă o modelare recurentă pentru cinematica unui robot paralel plan 3-PRP. Trei lan... more Articolul prezintă o modelare recurentă pentru cinematica unui robot paralel plan 3-PRP. Trei lanţuri cinematice plane ce conectează platforma mobilă a manipulatorului sunt situate în plan vertical. Cunoscând mişcarea platformei, se dezvoltă cinematica inversă şi se determină poziţiile, vitezele şi acceleraţiile robotului. Unele ecuaţii matriceale oferă expresi iterative şi grafice pentru deplasările, vitezele şi acceleraţiile celor trei acţionori de translaţie. Recursive modelling for the kinematics of a 3-PRP planar parallel robot is presented in this paper. Three planar chains connecting to the moving platform of the manipulator are located in a vertical plane. Knowing the motion of the platform, we develop the inverse kinematics and determine the positions, velocities and accelerations of the robot. Several matrix equations offer iterative expressions and graphs for the displacements, velocities and accelerations of three prismatic actuators.

Research paper thumbnail of Parallel Robot for Medical 3D-Ultrasound Imaging

2006 IEEE International Symposium on Industrial Electronics, 2006

... Simon Lessard, Ilian Bonev, Pascal Bigras Ecole de technologie superieure, Automated Manufact... more ... Simon Lessard, Ilian Bonev, Pascal Bigras Ecole de technologie superieure, Automated Manufacturing Engineering Department, Montreal, Canada e-mail ... Durand Institut de recherches cliniques de Montreal, Universite de Montreal, Canada Gilles Soulez, Guy Cloutier, Jacques ...

Research paper thumbnail of New XY-Theta Positioning Table with Partially Decoupled Parallel Kinematics

2006 IEEE International Symposium on Industrial Electronics, 2006

Parallel robots provide an efficient solution in a world demanding better positioning accuracy. T... more Parallel robots provide an efficient solution in a world demanding better positioning accuracy. These robots are preferred over their serial counterparts because each leg helps support the platform, thus reducing the need to add means for extra support. The problem with parallel robots though is that most are coupled and difficult to control. In this paper, new parallel robot architecture has been proposed that can deliver accurate movements in addition to being partially decoupled and fast. This is a significant technological advantage over current designs because a decoupled robot will be simpler to control as each actuator is independent. Furthermore, its displacement resolution is less variable throughout the workspace. To achieve the decoupled state, this parallel robot took the novel approach of having mixed legs. By comparing this robot to existing commercial devices through kinematic, singularity, workspace, velocity and dexterity analysis, this paper would like to show that this new design should be looked into further to create a precision positioning table that is parallel, decoupled, and highly accurate.

Research paper thumbnail of Mechanism of zinc sulphide oxidation

Thermochimica Acta, 1986

Abstract Investigations have been carried out on the thermodynamics, kinetics and mechanism of ox... more Abstract Investigations have been carried out on the thermodynamics, kinetics and mechanism of oxidation of ZnS. The following methods were used: thermodynamic, DT, TG, chemical, phase chemical, gaseous and X-ray (structural, phase, micro-) analyses, scanning electronic microscopy, stereomicroscopy, electronography, analysis of kinetic data, etc. Chemical potential diagrams (log p so 2 -log p o 2 ) have been constructed at various temperatures and the regions of stability of the separate compounds were defined. A multi-strata, strongly porous, finely grained oxide product has been obtained. The layers have a thickness of 5–20 μm and are marked off by cracks up to 1–2 μm wide. This determines the evolution of the oxidation process of particles of the floatation concentrate in a fluidized bed at the high temperature of roasting zinc concentrates under a kinetic regime. A mechanism is suggested for oxidation of a separate particle of ZnS, reporting both the evolution of the chemical process itself and the evolution of heat, heat and mass changes, and changes in the structure and porosity of the solid reagent and product. Structural models are suggested in oxidizing lamellae and spherical particles of ZnS.

Research paper thumbnail of An experimental study on the vibration response of a robotic machining system

Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 2013

Robotic machining is one of the most versatile manufacturing technologies around, whose emergence... more Robotic machining is one of the most versatile manufacturing technologies around, whose emergence helped reduce the machining cost of complex parts. However, its application is sometimes limited due to the low rigidity of the robot, whose stiffness leads to high vibration levels, which limit the quality and the precision of machined parts. In this study, the vibration response of a robotic machining system was investigated. To that end, a new method based on the variation of spindle speed was introduced for finishing the aluminum aerospace grade alloy (7075-T6) blocks. With the proposed method, the vibrations and the cutting force signal were collected and analyzed to find a reliable dynamic stability criterion, and the proposed criterion was validated using the machined surface roughness obtained. It was found that the directional root mean square (RMSdirectional) of the vibration signal is a good indicator for defining the degree of stability of the machining process. Moreover, it...

Research paper thumbnail of Detailed characterization of electron sources yielding first demonstration of European X-ray Free-Electron Laser beam quality

Physical Review Special Topics - Accelerators and Beams, 2010

Research paper thumbnail of Grafting in forestry

Research paper thumbnail of A study of work satisfaction among people, returning from peace-supporting mission

Research paper thumbnail of Academy of Sciences of the Ussr, Institute of Crystallography, Growth of Crystals (Selected Articles)

: Contents: The effect of anisotropy of properties of semiconductor crystals on segregation of im... more : Contents: The effect of anisotropy of properties of semiconductor crystals on segregation of impurities in a growing crystal; Mechanism of the oriented growth of crystalline substances (epitaxy); Deviation from Homogeneity in single crystals of gallium phosphide-gallium arsenide solid solutions grown by the epitaxial method; Some instances of change in the habit of crystals during epitaxial growth; Kinetics of the spontaneous transformation of the surface of a crystal-vapor system; and Growth and dislocation models of crystals.

Research paper thumbnail of Relationships between burn out syndrome and job satisfaction among cancer center personnel

Research paper thumbnail of Are Parallel Robots More Accurate Than Serial Robots?

Transactions of the Canadian Society for Mechanical Engineering, 2007

It is widely claimed that parallel robots are intrinsically more accurate than serial robots beca... more It is widely claimed that parallel robots are intrinsically more accurate than serial robots because their errors are averaged instead of added cumulatively, an assertion which has not been properly addressed in the literature. This paper addresses this void by comparing the kinematic accuracy of two pairs of serial-parallel 2-DOF planar robots. Only input errors are considered and all robots are optimized for accuracy, the only constraint being that they cover a given desired workspace. The results of this comparison seem to confirm that parallel robots are less sensitive to input errors than serial robots. However, this comparison is too limited to draw any general conclusions. Besides, it is virtually impossible to make a meaningful comparison between other pairs of serial and parallel robot. Therefore, there is no simple answer to this question of superiority.

Research paper thumbnail of On the terminology of the phenomena of mutual crystal orientation

Acta Crystallographica Section A, 1972

Research paper thumbnail of Anisometric growth of crystals with isometric structures

Acta Crystallographica Section A Foundations of Crystallography, 1984

GaN, a direct, wide energy gap mater~al jgap 3.5 eV/ is potentially suitable for optoelectronic d... more GaN, a direct, wide energy gap mater~al jgap 3.5 eV/ is potentially suitable for optoelectronic devices. The main reason for limited applicability are technological difficulties. The high decomposition pressure of N? leads to the thermal instability at temperatures above-900 o C under normal pressure. Another problem is a lack of good solvent for this mater~~l. The solubility of GaN in Ga at 11509C(is in order 10 % molar. Our studies of the thermodynamics of Ga-N 2 system show that the equilibrium pressure of N2 over GaN is much lower then previously predicted. Therefore the equilibrium conditions for GaN in gas pressure chamber were obtained up to 1700 o C, and the synthesis of

Research paper thumbnail of Clarification of Some Aspects of Respiration with the Help Electronic Registration of Respiratory Movements

Nauchni trudove na Visshiia meditsinski institut, Sofiia, 1964

Research paper thumbnail of Dentistry in Bulgaria

Research paper thumbnail of Numerical Computation and Avoidance of Manipulator Singularities

This thesis develops general solutions to two open problems of robot kinematics: the exhaustive c... more This thesis develops general solutions to two open problems of robot kinematics: the exhaustive computation of the singularity set of a manipulator, and the synthesis of singularity-free paths between given configurations. Obtaining proper solutions to these problems is crucial, because singularities generally pose problems to the normal operation of a robot and, thus, they should be taken into account before the actual construction of a prototype. The ability to compute the whole singularity set also provides rich information on the global motion capabilities of a manipulator. The projections onto the task and joint spaces delimit the working regions in such spaces, may inform on the various assembly modes of the manipulator, and highlight areas where control or dexterity losses can arise, among other anomalous behaviour.

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1986

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1990

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1995

Research paper thumbnail of Bulgaria

World Directory of Crystallographers, 1997

Research paper thumbnail of Self motions of a special 3-(R)under-barPR planar parallel robot

Articolul prezintă o modelare recurentă pentru cinematica unui robot paralel plan 3-PRP. Trei lan... more Articolul prezintă o modelare recurentă pentru cinematica unui robot paralel plan 3-PRP. Trei lanţuri cinematice plane ce conectează platforma mobilă a manipulatorului sunt situate în plan vertical. Cunoscând mişcarea platformei, se dezvoltă cinematica inversă şi se determină poziţiile, vitezele şi acceleraţiile robotului. Unele ecuaţii matriceale oferă expresi iterative şi grafice pentru deplasările, vitezele şi acceleraţiile celor trei acţionori de translaţie. Recursive modelling for the kinematics of a 3-PRP planar parallel robot is presented in this paper. Three planar chains connecting to the moving platform of the manipulator are located in a vertical plane. Knowing the motion of the platform, we develop the inverse kinematics and determine the positions, velocities and accelerations of the robot. Several matrix equations offer iterative expressions and graphs for the displacements, velocities and accelerations of three prismatic actuators.

Research paper thumbnail of Parallel Robot for Medical 3D-Ultrasound Imaging

2006 IEEE International Symposium on Industrial Electronics, 2006

... Simon Lessard, Ilian Bonev, Pascal Bigras Ecole de technologie superieure, Automated Manufact... more ... Simon Lessard, Ilian Bonev, Pascal Bigras Ecole de technologie superieure, Automated Manufacturing Engineering Department, Montreal, Canada e-mail ... Durand Institut de recherches cliniques de Montreal, Universite de Montreal, Canada Gilles Soulez, Guy Cloutier, Jacques ...

Research paper thumbnail of New XY-Theta Positioning Table with Partially Decoupled Parallel Kinematics

2006 IEEE International Symposium on Industrial Electronics, 2006

Parallel robots provide an efficient solution in a world demanding better positioning accuracy. T... more Parallel robots provide an efficient solution in a world demanding better positioning accuracy. These robots are preferred over their serial counterparts because each leg helps support the platform, thus reducing the need to add means for extra support. The problem with parallel robots though is that most are coupled and difficult to control. In this paper, new parallel robot architecture has been proposed that can deliver accurate movements in addition to being partially decoupled and fast. This is a significant technological advantage over current designs because a decoupled robot will be simpler to control as each actuator is independent. Furthermore, its displacement resolution is less variable throughout the workspace. To achieve the decoupled state, this parallel robot took the novel approach of having mixed legs. By comparing this robot to existing commercial devices through kinematic, singularity, workspace, velocity and dexterity analysis, this paper would like to show that this new design should be looked into further to create a precision positioning table that is parallel, decoupled, and highly accurate.

Research paper thumbnail of Mechanism of zinc sulphide oxidation

Thermochimica Acta, 1986

Abstract Investigations have been carried out on the thermodynamics, kinetics and mechanism of ox... more Abstract Investigations have been carried out on the thermodynamics, kinetics and mechanism of oxidation of ZnS. The following methods were used: thermodynamic, DT, TG, chemical, phase chemical, gaseous and X-ray (structural, phase, micro-) analyses, scanning electronic microscopy, stereomicroscopy, electronography, analysis of kinetic data, etc. Chemical potential diagrams (log p so 2 -log p o 2 ) have been constructed at various temperatures and the regions of stability of the separate compounds were defined. A multi-strata, strongly porous, finely grained oxide product has been obtained. The layers have a thickness of 5–20 μm and are marked off by cracks up to 1–2 μm wide. This determines the evolution of the oxidation process of particles of the floatation concentrate in a fluidized bed at the high temperature of roasting zinc concentrates under a kinetic regime. A mechanism is suggested for oxidation of a separate particle of ZnS, reporting both the evolution of the chemical process itself and the evolution of heat, heat and mass changes, and changes in the structure and porosity of the solid reagent and product. Structural models are suggested in oxidizing lamellae and spherical particles of ZnS.

Research paper thumbnail of An experimental study on the vibration response of a robotic machining system

Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, 2013

Robotic machining is one of the most versatile manufacturing technologies around, whose emergence... more Robotic machining is one of the most versatile manufacturing technologies around, whose emergence helped reduce the machining cost of complex parts. However, its application is sometimes limited due to the low rigidity of the robot, whose stiffness leads to high vibration levels, which limit the quality and the precision of machined parts. In this study, the vibration response of a robotic machining system was investigated. To that end, a new method based on the variation of spindle speed was introduced for finishing the aluminum aerospace grade alloy (7075-T6) blocks. With the proposed method, the vibrations and the cutting force signal were collected and analyzed to find a reliable dynamic stability criterion, and the proposed criterion was validated using the machined surface roughness obtained. It was found that the directional root mean square (RMSdirectional) of the vibration signal is a good indicator for defining the degree of stability of the machining process. Moreover, it...

Research paper thumbnail of Detailed characterization of electron sources yielding first demonstration of European X-ray Free-Electron Laser beam quality

Physical Review Special Topics - Accelerators and Beams, 2010