ABSTRACT A two-wheeled self-balancing robot is a special type of wheeled mobile robot, its balance problem is a hot research topic due to its unstable state for controlling. In this paper, human transporter model has been established....
moreABSTRACT A two-wheeled self-balancing robot is a special type of wheeled mobile robot, its balance problem is a hot research topic due to its unstable state for controlling. In this paper, human transporter model has been established. Kinematic and dynamic models are constructed and two control methods: Proportional-integral-derivative (PID) and Linear-quadratic regulator (LQR) are implemented to test the system model in which controls of two subsystems: self-balance (preventing system from falling down when it moves forward or backward) and yaw rotation (steering angle regulation when it turns left or right) are considered. PID is used to control both two subsystems, LQR is used to control self-balancing subsystem only. By using simulation in Matlab, two methods are compared and discussed. The theoretical investigations for controlling the dynamic behavior are meaningful for design and fabrication. Finally, the result shows that LQR has a better performance than PID for self-balancing subsystem control.
The concept of a medical parallel manipulator applicable to chest compression in the process of cardiopulmonary resuscitation (CPR) is proposed in this paper. According to the requirement of CPR action, a...
moreThe concept of a medical parallel manipulator applicable to chest compression in the process of cardiopulmonary resuscitation (CPR) is proposed in this paper. According to the requirement of CPR action, a three-prismatic-universal-universal (3-PUU) translational parallel manipulator (TPM) is designed for such applications. And a thorough analysis involving the issues of kinematics, dynamics, and control have been performed for the 3-PUU
The joint parameters of redundant manipulators are prerequisite data for effective dynamics control. An identification method via fuzzy theory and genetic algorithm has been presented to study modular redundant robots. The genetic...
moreThe joint parameters of redundant manipulators are prerequisite data for effective dynamics control. An identification method via fuzzy theory and genetic algorithm has been presented to study modular redundant robots. The genetic algorithm is used in the fuzzy optimization expecting to obtain global optimal solutions. Experimental modal analysis and finite element method have been exploited in dynamics modeling. The joint
ABSTRACT In this paper, a (t, n) threshold signature scheme is constructed without a trusted party, which has provable security in Mobile Ad Hoc Network, and its security fits with terminal device with limited resource. Any participant...
moreABSTRACT In this paper, a (t, n) threshold signature scheme is constructed without a trusted party, which has provable security in Mobile Ad Hoc Network, and its security fits with terminal device with limited resource. Any participant can compute the system public key, but can not recover the system secret key without any other t-1 participants' help. In this proposed scheme, ECC-based threshold polynomial is intrinsically safer and easier to realize than the presented schemes' based on prime-field. A verifiable threshold signature scheme is proposed such that all participants must provide confidential and verifiable information λj each other. We design a new bilinear pairing-based threshold signature scheme which is efficient in terms of both the communication overhead and the computational requirement. So the new threshold signature scheme is more secure, verifiable, and efficient compared with the presented schemes for Mobile Ad Hoc Network.
Due to the time-consuming calculation for the forward kinematics of a 3-PRS (prismatic-revolute-spherical) parallel manipulator, neither the kinematic nor dynamic control algorithm can be implemented on real time. To deal with such...
moreDue to the time-consuming calculation for the forward kinematics of a 3-PRS (prismatic-revolute-spherical) parallel manipulator, neither the kinematic nor dynamic control algorithm can be implemented on real time. To deal with such problem, the forward kinematics is solved by means of artificial neural network (NN) approach in this paper. Based on the trained NN, the kinematic control of the manipulator
... 4. B. Velocity and Isotropy Analysis Referring to Fig. ... IV. WORKSPACE ANALYSIS It is known thatparallel manipulators have relatively small workspace compared with their serial counterparts. Fortunately, this is no longer a drawback...
more... 4. B. Velocity and Isotropy Analysis Referring to Fig. ... IV. WORKSPACE ANALYSIS It is known thatparallel manipulators have relatively small workspace compared with their serial counterparts. Fortunately, this is no longer a drawback for nano scale manipulation. ...
... A novel compliant parallel manipulator (CPM) is designed to achieve such purposes ... the developed PRB model of the CPM, the kinematic modelings and velocity analysis are performed ... And in Section IV, the isotropy of the...
more... A novel compliant parallel manipulator (CPM) is designed to achieve such purposes ... the developed PRB model of the CPM, the kinematic modelings and velocity analysis are performed ... And in Section IV, the isotropy of the ma-nipulator is investigated, where dexterity measures ...
The stiffness modeling for a compliant parallel manipulator (CPM) is very important since it provides a basis for the characterization of static, modal, and dynamic behavior of the CPM. This paper presents the stiffness modeling of a...
moreThe stiffness modeling for a compliant parallel manipulator (CPM) is very important since it provides a basis for the characterization of static, modal, and dynamic behavior of the CPM. This paper presents the stiffness modeling of a three-prismatic-revolute-cylindrical (3-PRC) CPM with orthogonally mounted actuators, that is designed to provide three spatial translational DOF for nano scale manipulation. A straightforward method
This paper presents the controller design of an XY parallel micropositioning stage aiming at a sub-micron accuracy for micro scale manipulation. Owning to the decoupled design of the mechanism, a simple single-input-single-output (SISO)...
moreThis paper presents the controller design of an XY parallel micropositioning stage aiming at a sub-micron accuracy for micro scale manipulation. Owning to the decoupled design of the mechanism, a simple single-input-single-output (SISO) PID controller is adopted for each axis. To compensate for the hysteresis arising from piezoelectric actuator, credit assigned CMAC (cerebellar model articulation controller) neural network with adjustable learning rate is employed into the PID control. Experimental results show that the hysteresis of the stage has been significantly reduced by the CMAC-based PID controller and the stage can achieve a sub-micron positioning accuracy, which demonstrate the effectiveness of the designed controller as well.
In this paper, a sliding mode control with perturbation estimation (SMCPE) using an extended Kalman filter (EKF) is proposed for the motion tracking control of a micropositioning system with piezoelectric actuation. Based on the solely...
moreIn this paper, a sliding mode control with perturbation estimation (SMCPE) using an extended Kalman filter (EKF) is proposed for the motion tracking control of a micropositioning system with piezoelectric actuation. Based on the solely measurable position information, the EKF on-line estimates not only the velocity but also the hysteresis term, which are used by the SMCPE for real-time control. The feasibility of the proposed control scheme is demonstrated by experimental studies on a XYZ micropositioning stage prototype. Results show that the EKF-based sliding mode control can reduce the hysteresis to a negligible level and lead to a motion tracking with submicron accuracy, which provides a sound base of practical control of the micropositioning system for micro/nano scale manipulation.
ABSTRACT The UAV quadrotor is considerably difficult to be controlled due to its inherently unstable and complex multi-variable properties. To realize the control, a nonlinear dynamic model is firstly derived and formulated. A control...
moreABSTRACT The UAV quadrotor is considerably difficult to be controlled due to its inherently unstable and complex multi-variable properties. To realize the control, a nonlinear dynamic model is firstly derived and formulated. A control approach employing hierarchical multiple-layer structure is then developed. The detailed hardware components, software as well as the working principle of the system are described. The entire UAV control system is tested and verified in actual flight tests.
The kinematic design of a medical parallel manipulator used for chest compressions in the process of cardiopulmonary resuscitation (CPR) is presented in this paper. According to the requirements of CPR action from medical viewpoints, a...
moreThe kinematic design of a medical parallel manipulator used for chest compressions in the process of cardiopulmonary resuscitation (CPR) is presented in this paper. According to the requirements of CPR action from medical viewpoints, a 3-PRS (prismatic-revolute-spherical) parallel manipulator (PM) is designed utilizing an architectural optimization methodology for such applications. The dynamic modeling is performed for the 3PRS PM by two different approaches of Lagrangian formulation and virtual work principle utilizing a simplification hypothesis. Simulation results verify the accuracy of the derived dynamic equations quantitatively, and demonstrate the rationality of the adopted simplified hypothesis. The research work presented here provides a sound base to develop a new medical manipulator to assist in CPR operation, which is expected to reduce the workload of doctors in rescuing patients significantly
This paper presents the design process of a totally decoupled flexure-based XYZ compliant parallel-kinematics micropositioning stage. The uniqueness of the proposed XYZ stage lies in that it consists of three monolithic limbs and has both...
moreThis paper presents the design process of a totally decoupled flexure-based XYZ compliant parallel-kinematics micropositioning stage. The uniqueness of the proposed XYZ stage lies in that it consists of three monolithic limbs and has both input and output decoupling properties. The output decoupling is allowed by the employment of a proposed 2-D compound parallelogram flexure, and the input decoupling is
In this paper, a concept of totally decoupling is proposed for the design of a flexure parallel micromanipulator with both input and output decoupling. Based on flexure hinges, the design procedure for an XY totally decoupled parallel...
moreIn this paper, a concept of totally decoupling is proposed for the design of a flexure parallel micromanipulator with both input and output decoupling. Based on flexure hinges, the design procedure for an XY totally decoupled parallel stage (TDPS) is presented, which is featured with decoupled actuation and decoupled output motion as well. By employing (double) compound parallelogram flexures and
