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The manipulators whose degrees of freedom are high are called “hyper-redundant manipulators”. High degrees of freedom make them dexterous and able to avoid the obstacles. Here, the term hyper-redundant manipulator is used for the manipulators which are produced by cascading the serial or parallel mechanisms on top of each other, as modules. The discrete actuators can have a few stable states. These actuators usually need no feedback in their control. This causes them to have a simpler control, to be cheaper, more precise, and to improve the repeatability. So far, several methods have been proposed to solve inverse kinematics problem of discretely actuated hyper-redundant manipulators. The two-by-two searching method is better than the other methods in terms of CPU-time and error. In this paper, the mentioned method is generalized by choosing an arbitrary number of modules as pending modules in each step of searching, instead of necessary two. Also, the effect of the number of pending modules on CPU-time and error is investigated. For this purpose, two planar and spatial manipulators are introduced to define the inverse kinematics problems and then the results are analyzed and compared.

Nanomanipulation and displacement of nanoparticles has found wide applications in various sciences today.One of the basic tools for performing the Nanomanipulation process is the atomic force microscope.Today the atomic force microscope has found various applications, including surface imaging, manipulation and movement of particles, extracting the properties of materials and textures.The manipulation of nanoparticles usually involves two phases.The first phase includes the extraction of the critical force and the critical time before the start of the particle movement.The second phase also includes the investigation of particles during movement during Nano manipulation and displacement.Due to the fact that in micro/Nano dimensions,surface forces are more effective than volume forces,so it is very important to choose the appropriate contact model in modeling and simulating the Nano manipulation process.Various parameters affect contact models on the micro/Nano scale.In this research, the effect of different parameters on Hertz, JKR and DMT contact models has been investigated.For this purpose, in order to investigate the effect of different input parameters, the statistical method of sensitivity analysis called E-fast, which is one of the fast methods,has been used.The input parameters examined in this research include tip radius,volume of the particle,elastic modulus of the tip,elastic modulus of the particle,Poisson's coefficient of the tip and Poisson's coefficient of the particle, as well as penetration depth and force, which are explained as output parameters.The obtained results show that the volume of the target particles and the tip radius have a great influence on the force and depth of penetration in the contact models

In this paper, dynamic model of r cooperative manipulators with n_m links derived by using recursive Gibbs-Appell formulation. Object grasped fully constrained by the manipulator’s end effector and manipulators transport the object simultaneously. For computing the system equations, first the object and manipulators dynamic equations developed independently. Therefore, by preparing the constraint equations, the end effectors and object inter connection forces and torques omitted for the constrained equations. By arranging these equations, the final form of motion equations in joint space evaluated. Next, the forward dynamic equations simulated by MATLAB software and compared with ADAMS software. For inverse dynamic solution, with considering the joints redundancy, two proper solution selected among appropriated one. In the first case, the solution chosen by considering the force extracted on the object by the manipulators. While, the force only cause the object manipulation and omitted the object internal force and stress. For the second one, optimum torques computed using Lagrange multiplier method and defining a cost function with assuming the arbitrary energy distribution between manipulator’s joints. At the end, the dynamic load carrying capacity calculated in all methods.

Different definitions of nano-technology prove this truth that nano-technology includes wide range of various scientific fields. In fact, nano-technology is an interdisciplinary science and a new approach to the all domains. In Nanomanipulation process by utilizing Atomic Force Microscope, contact models play important role for determining critical force and time which constituent the first phase of this process. In current study, two contact stages in Nanomanipulation of gold cylindrical micro/nano particles are investigated. First stage is the contact of micro/nanoparticles and substrate and the second one is the contact between cantilever tip and micro/nanoparticles. For the first stage, five significant contact models including Hertz, Lundeberg, Dawson, Nikpour and Heoprich have been used. Also in the second stage, contact models of Hertz and JKR have been applied. Dawson model predicts maximum and Nikpour model predicts the least amounts of deformation and penetration depth for the contact of the first stage of deformation between substrate and gold cylindrical micro/nanoparticles. Also the deformation between cylindrical particles and spherical tip apex has the minimum amount in Hertz model and the highest amount of deformation and penetration depth have been showed in JKR model due to regarding adhesion forces. Generally, the results indicate increasing the angle of tip apex along the z axis leads to decrease of penetration depth and the amount of deformation between particles and substrate which Lundeberg model has been demonstrated the least amount and Nikpour model has been showed the highest amount of decrease.

In this paper, the design and construction of a new binary pneumatic actuated hyper-redundant manipulator is presented. The discretely actuated hyper-redundant manipulators have advantages such as wide workspace, the ability of obstacle avoidance and simple control. Despite of these advantages, few prototypes have been made so far, which each of them has some defects. These defects are small movement range, fairly high cost, and accelerated and impulsive motion. To solve these problems, the 3-revolute prismatic spherical parallel mechanisms (3-RPS) are used as modules in this paper. So the cost is reduced due to the lower number of legs. Also, the motion range has been increased by replacing the spherical joints with universal joints. The movements of the manipulator have been effectively more uniform and softer by using flow control valves on cylinders. Finally, several tests are conducted to determine how the manipulator moves and the results are presented.

The production and grinding of rotating parts with parallel and angular misalignment is one of the topics issues in the field of Manufacturing engineering. To connect these types of parts to the grinding machine, it is necessary to use three jaw chuck or Jig & Fixtures that are complicated and Time-consuming. This study examines the feasibility of using the 6RUS parallel robot as a six-degree of freedom chuck in the grinding machine. This research will include the design of the 6RUS robot and the reverse kinematics and robot workspace, and then examine the feasibility of using the robot as a six-degree of freedom chuck, which will analyze strain and frequency stress in finite element software includes.

As nanotechnology develops, atomic force microscope Nano-robots attracted the attentions as an efficient instrument in order to Nano-structures transfer and construction. Lack of possibility of simultaneously observing the Nano-particles controlled pushing operation is one of the most important limitations on this method. In present research a virtual reality environment is used for observing the operation process in order to eliminate the limitations. At first, the images obtained from the AFM Nano-robots were processed in the simulation performed and then Nano-particles dimensions were determined. Then, the particles were transferred using Nano-particles transference dynamic simulation and simulating the critical time-force diagram. The simulations developed in order to make use of the rectangular, dagger and V-shaped cantilevers. The virtual reality environment provided allowed for the modeling applicability accurate process simulation for users.

In the most contact theories such as Hertz, DMT and JKR, which are the most practical contacts models, biological particles are considered as a spherical elastic particle, which is not the best assumption. In this assumption, the history of loadings are not considered in that the history of strains and stresses will not analyzed properly. Therefore, in the first part of this paper, three models of elastic in spherical geometry have been developed to the viscoelastic models. By simulations and comparing the results with the experimental data of MCF-10A (breast-cancer cell), which is derived by Atomic Force Microscopy, it is revealed that viscoelastic models are more accurate than elastic models in the force-indentation curves. Then, according to the fact that most bacteria's geometry is cylindrical, contact theory for a sphere and cylinder have been developed and simulated for three groups of nanobacteria (Epidermidis, SallyVirus, and Aureus). By comparing simulations results with experimental data we observe that elastic models are not reasonable and contacts radius in viscoelastic model are smaller than they were for elastic models.

In this paper, by using the classical molecular dynamics and coarse grained molecular dynamics, the mechanism of automatic nanomanipulation with atomic force microscope nano-robot was modelled and it was shown that the rupture of tip is the most error source in the automatic nano-manipulation process, where is manipulation of particles on the substrate frequently. By this, to prevent from the non-favorable effects of deformation of tip on the result of nano-manipulation, a control plan was introduced. By definition of root mean squares as a criterion for measurement of the level of deformation, a simple feedback of it was used to control the system. After that the model proposed and validated in comparison with some experimental works, by using the coarsening the molecular dynamics, the system is converted into a relatively simple model and was suggested for implementation into the manipulation processes. By using this model, it was observed that although the aluminum tip leads to the worst result, by using the shape feedback, the positioning error has been reduced considerably. Positioning error without and with feedback was reported for a nickel tip as 37.77% and 17.77%, respectively. These values show the efficiency of the presented shape feedback approach.

To investigate the effects of drugs on viruses, interactions between proteins and inserting desirable genetic changes on DNA, precise study of biological cells is a necessary demand for nowadays. In this way, exploring mechanical properties of these particles and their mechanical behavior in different situations is needed; manipulation of bioparticles in nano scale is an important process for investigating nanoparticles behavior; because the amount of exerted force, deformation and investigating the damage possibility can provide useful information. In this paper, a molecular dynamics modeling of bioparticles nanomanipulation based on AFM has been done. Bioparticles include virus, protein and ssDNA. The main goal of this study is investigating the substrate effect on exerted force on the bioparticles and exploring damage possibility. Three types of substrates have been used, including silicon, graphene sheet and golden substrate. Widespread usage and low level interactions with other materials are the reasons of choosing these substrates. Results show that on gold substrate, the maximum manipulation force occurs and damage possibility is high. Also on graphene substrate manipulation force and deformation of particle are more than the silicon substrate.

In this paper, surface roughness of HT29 cancerous is determined using topography images obtained by Atimic Force Microscopy (AFM). The mean radiuses of cell and substrate surface asperities are determined, based on results of conducted roughness analysis and Rabinovich roughness theory. These values have been applied in the equations of rough particle nanomanipulation dynamic model and the amounts of critical force and time are simulated. Based on results, the rolling mode is the dominant dynamic mode at the onset of cells movement and the analysis based on rabinovich model predict lower amounts of critical force and time compared to Rumpf model based analysis.

Nowadays, movement of micro/nano particles has been attracted considerable attention to manufacturing different devices in micro/nano scale and medical and biological applications. Atomic Force Microscope Probe is widely being used for precise small scale movements. During nano-manipulation, micro/nano particles can be moved to a desired destination with high accuracy using Atomic Force Microscope while in contact mode with precise probe control. In this article, by selecting a proper amount of torque applied to the probe tip, deviation from the center and movement of probe have been investigated to assure the contact between the probe and micro/nano particle. Different liquid environments (water, alcohol, and plasma) with different micro/nano particles including biological and non-biological have been used for this investigation. In addition, using sliding mode control, Atomic Force Microscope Probe was used in different environments such as water, alcohol, and plasma. Obtained results showed that the time needed to control different micro/nano particles in plasma was shorter than that of in water; also the time needed in water was shorter than that of in alcohol.

In this paper, the modeling and simulation of manipulation of carbon nanoparticles have been investigated. The geometry plays a significant role in the dynamic behavior of nanoparticles manipulation and the evaluation of different geometric shapes of nanoparticles in this process is very important. To examine the geometry effects, the manipulation of a different kind of the nano-carbon allotropes has been studied. Furthermore, the manipulation of carbon nanotubes with different diameter has been simulated. For this purpose, the molecular dynamics method has been used to improve our knowledge and understanding about the nanomanipulation processes and dynamics. In the manipulation of carbon allotropes, the results indicated that more spherical allotrope Modes away, the easier manipulation process occurred and the forces on the probe have been reduced; this is due to the curvature of tip and nanoparticle. The results of nanotubes manipulation showed that increasing the diameter of the nanotube causes to increase the force on the probe. The indentation depth was extracted for each nanotube during the manipulation process. The results indicated that the indentation depth increases versus diameter increasing. According to the application of carbon-based structures and nanotubes as the drug carriers in medicine, such this simulation studies can reduce time and cost of experimental projects in this field.

Full feedback data is mostly essential in control design. The measurement of the variation of flexible joint robot (FJR) actuators is not easy as the measurement of the changes of FJR links’ angles. The measurement of the states is also affected by noise, and the disturbance in the workspace of the robot is not ignorable. Hence a state observer or a nonlinear estimator is necessary to improve the performance of the dynamic system. The state-dependent Riccati equation (SDRE) is one of the most promising nonlinear optimal control methods for estimating variables of systems. Systematic procedure, simple structure, and incorporating wide range of systems (under observability condition) are some advantages of SDRE method. The majority of nonlinear techniques linearize the model, but the SDRE directly uses the nonlinear state space; it is one of the reasons for its precision and flexibility in design with respect to other methods. The goal of this work is to merge the SDRE controller and estimator simultaneously to reduce the state error of the system in presence of external disturbance and measurement noise. So, first, the controller and the observer formulation has been stated. Then, the procedure has been applied to design and to simulate a 3 DOF robot arm with flexible joints. Next, the process has been tested experimentally using Scout robot and the simulation results have been verified. Finally, the proposed method of this paper has been compared with the optimal sliding mode.

In nanoparticles manipulation with atomic force microscope for modeling exact manipulation dynamics and prevent of damaging nanoparticles, it is necessary to compute critical force. For modeling dynamics and computing critical force that apply to nanoparticles it is necessary to modeling cantilever stiffness and determine sensitive geometrical parameters which are effect cantilever stiffness and critical force. In this paper at first it is investigated on two common different kinds of cantilevers which are V-shaped and dagger cantilevers. For modeling V-shaped cantilever stiffness this cantilever is divided into two parts a triangular head section and two slanted rectangular beams. After that the stiffness of each part is modeled separately and the total stiffness is computed. For modeling dagger cantilever stiffness it is used the same method and cantilever is divided into two parts a triangular head section and a rectangular beam and then the total stiffness is computed. Cantilevers stiffness and critical force in manipulation of biological particles and non-biological particles are very important because of that it is used EFAST sensitivity analyses for selecting suitable cantilever and its parameters. In this paper it has been shown that the dagger-shaped cantilever is more suitable for the manipulation of biological particles.

Nowadays one of the arguments that have been raised in the world of nanotechnologies is moving or manipulation nanoparticles. This discussion is important because the displacement of nanoparticles can make structurally different than what is currently available. So to achieve this goal, the atomic force microscope probe is used as manipulator. In this way, the use of nanoparticles by pulling or pushing on the surface, are displaced and brought to the desired point. If you apply too much force is needed, Nanoparticle Continued movement (sliding or rolling) after standing atomic force microscopy probes and away from the desired final. On the other hand, if the force is low, so that it can’t overcome the static friction force, Nanoparticles will be no movement. So finding the optimal force is important in nanomanipulation. In this paper, with using nanoparticle dynamic simulation, the governing equations on nanoparticle are derived and simulated during manipulation happen that they can be used to obtain the critical force and time for gold, yeast and platelets nanoparticles, in gaseous, water, alcohol, and plasma environments. By comparing the results obtained in this paper, it is concluded that the movement of particles in different biological environments starts later and by a force of higher magnitude relative to the gaseous medium.

This paper presents the investigation of general formulation and numerical solution of the dynamic load carrying capacity (DLCC) of flexible link manipulator. The proposed method is based on open loop optimal control problem. A two point boundary value problem (TPBVP) is provided, extracted from the Pontryagin's minimum principle. The indirect approach is employed to derive optimality conditions. The system’s dynamics equation of motion is obtained from Gibbs-Appell (G-A) formulation and assumed mode method (AMM). Elastic properties of the links are modeled according to the assumption of Timoshenko beam theory (TBT) and its associated mode shapes. As TBT is more accurate compared with the Euler-Bernoulli beam theory, it is exploited for mathematical modeling of flexible links. The main contribution of the paper is to calculate the maximum allowable load of a flexible link robot while an optimal trajectory is provided. Finally, the result of the simulation and experimental platform are compared for a two-link flexible arm to verify the introduced technique. The efficiency of the proposed method is illustrated by performing some simulation studies on the IUST flexible link manipulator. Simulation and experimental results confirm the validity of the claimed capability for controlling point-to-point motion of the proposed method and its application toward DLCC calculation.

In this paper we developed and modeled elastic - plastic contact theories for soft spherical nano - bacteria to be applied in manipulation of various micro/nanobio particles based on atomic force microscopy. First, we simulated elastic contact for three types of nano - bacteria: S. epidermidis, S. salivarius and S. aureus, using Hertz contact model and finite element. Comparing simulation results of elastic contact with experimental data showed that considering elastic contact for simulating the contact of nano - bio particles is not appropriate and will yield incorrect results. Therefore, in this research, we tried to develop and simulate Chang elastic - plastic contact theory to be applied in simulation of contact mechanics for application in simulating manipulation. Comparing simulation of Chang contact theory with available experimental data and the results from contact simulation of Chen et al showed that Chang’s complete elastic - plastic theory yields desirable results. Comparing the diagram of contact radius in terms of indentation in Hertz and Chang theories showed that the created contact radius in elastic - plastic state is larger than contact radius in elastic state.

This paper presents a research into the progress of modeling of N-viscoelastic robotic manipulators. The governing equations of the system is obtained by using Gibbs-Appell (G-A) formulation and Assumed Mode Method (AMM). When the beam is short in length direction، shear deformation is a factor that may have substantial effects on the dynamics of the system. So، in modeling the assumption of Timoshenko Beam Theory (TBT) and its associated mode shapes has been considered. Although considering the effects of damping in continuous systems makes the formulations more complex، two important damping mechanisms، namely، Kelvin-Voigt damping as internal damping and the viscous air damping as external damping have been considered. Finally، to validate the proposed formulation a comparative assessment between the results achieved from experiment and simulation is presented in time domain.

In this study, mathematical modeling and dynamic response of nonholonomic wheeled mobile robotic manipulator that consists of a serial manipulator with both Revolute-Prismatic (R-P) joints and an autonomous wheeled mobile platform is considered. To avoid the Lagrange multipliers associated with the nonholonomic constraints the approach of Gibbs-Appell formulation in recursive form is adopted. For modeling the system completely and precisely the coupling effects due to the simultaneous rotating and sliding motion of the rigid arms as well as both nonholonomic constraints associated with the no-slipping and the no-skidding conditions are included. Finally, the analysis of a mobile manipulator with two (R-P) joints is considered.In this study, mathematical modeling and dynamic response of nonholonomic wheeled mobile robotic manipulator that consists of a serial manipulator with both Revolute-Prismatic (R-P) joints and an autonomous wheeled mobile platform is considered. To avoid the Lagrange multipliers associated with the nonholonomic constraints the approach of Gibbs-Appell formulation in recursive form is adopted. For modeling the system completely and precisely the coupling effects due to the simultaneous rotating and sliding motion of the rigid arms as well as both nonholonomic constraints associated with the no-slipping and the no-skidding conditions are included. Finally, the analysis of a mobile manipulator with two (R-P) joints is considered.

Piezoelectric microbeams are special types of beams applicable to the atomic force microscope (AFM). Having piezoelectric layers, they are capable of selfactuating using the voltage imposed on the piezoelectric layer. The present paper discusses the vibrating behavior of piezoelectric microbeams, with respect to the hydrodynamic forces imposed by a fluid. To do so, considering Hamiltons principle and assumptions of the Euler-Bernoulli theory, the dynamic modeling of a microbeam was carried out and the differential equation of vibrating motion was extracted. As it is very difficult to determine the exact amount of hydrodynamic force imposed on a beam, the hydrodynamic forces were approximated using string sphere modeling. The results obtained from dynamic modeling were compared with experimental ones. The results show that sphere string modeling can favorably model natural frequency and the resonance amplitude of piezoelectric microbeams in a liquid environment. The results show that the vibrating motion (natural frequency and resonance amplitude) of a microbeam in liquid is under the influence of fluid density, due to the damping of liquid and additional mass; it is also seen in the higher vibrating modes. By approaching the microbeam to the sample surface and intensifying squeeze force, the results show further amplitude decrease. The amplitude reduction at higher densities and low angles of the microbeam to the horizon is due to the intensification of compression force. When the interaction force between the probe tip and sample surface is intensified, and when there is a very short distance between the probe tip and sample surface (as small as a nanometer), amplitude is affected. According to the DMT model, there is a direct relationship between the interaction force between the tip and sample surface and the radius of the probe tip. Therefore, the more the radius of the probe tip, the more the interaction force will be. The increase of this force will be followed by a decrease in vibrational motion amplitude.

The main goal of this paper is to present a mathematical model for inverse dynamic equation of elastic robotic manipulator with revolute-prismatic joints. Due to the fact that there is no limitation on the number of mechanical arms، the proposed model must be extracted based on a systematic and automotive algorithm. Also according to the high computational complexity، the equations should be formed by a recursive formulation. Hence، a recursive and systematic methodology for deriving the equation of motion of elastic robotic arm with revolute-prismatic joints is presented. The inverse dynamic equations for this robotic system are obtained based on Gibbs-Applle formulation. All dynamic expressions of a link are expressed in the same link local coordinate system. Finally، in order to show the ability of this formulation in deriving and solving the equation of motion of such systems، a computational simulation for a flexible single robotic arm with revolute-prismatic joint is presented.

The main purpose of this paper is to derive the inverse dynamic equation of motion of n-rigid robotic manipulator that mounted on a mobile platform, systematically. To avoid the Lagrange multipliers associated with the nonholonomic constraints the approach of Gibbs-Appell formulation in recursive form is adopted. For modeling the system completely and precisely the dynamic interactions between the manipulator and the mobile platform as well as both nonholonomic constraints associated with the no-slipping and the no-skidding conditions are also included. In order to reduce the computational complexity, all the mathematical operations are done by only 3×3 and 3×1 matrices. Also, all dynamic characteristics of a link are expressed in the same link local coordinate system. Finally, a computational simulation for a manipulator with five revolute joints that mounted on a mobile platform is presented to show the ability of this algorithm in generating the equation of motion of mobile robotic manipulators with high degree of freedom.

Flexible manipulators have plentiful applications in Aero-Space fields, due to their less weight and maneuverability. In fact, the ratio of their load carrying capacity to their weight, make them more excellent over their rigid ones. Moreover, these manipulators are known as good candidates in Aero-Space applications because of their less energy consumption, and smaller actuators. In this paper, the dynamic modeling of the flexible manipulators are performed using Finite Element Method (FEM), and optimal control of point-to-point motion of robot is done via optimal control method. To dynamic modeling of flexible manipulator, each link of the robot is divided into sufficient elements, and total displacement of the element is presumed as summation of a rigid displacement and a displacement because of flexibility. By means of Lagrange’s principle, dynamic equations of the flexible robot are derived, and the effect of number of the on dynamic motion of the robot is considered. Also, for the optimal point-to-point motion planning of the elastic manipulator, the nonlinear dynamic equations of the robot is assumed as constraints of optimal control problem, and a proper cost function is defined including torque and speed terms. Then, variation of calculus and Pontryagin’s minimum principle are employed and optimality conditions are resulted in a set of nonlinear differential equations, which is solved numerically. The priority of the optimal control method on the optimal motion planning of the flexible manipulator is discussed, and simulations for a single-link elastic robot illustrate the applicability of the method