THE EFFECT OF TIME INFLUENCE ON PHYSIOLOGICAL PARAMETERS FOLLOWING KETAMINE AND DIAZEPAM ADMINISTERATION IN CATS

Objective: The present study aims to determine the effect of time influence on rectal temperature, respiratory and pulse rate, onset and duration of action, duration of recumbency and recovery following ketamine and diazepam administration in cats.Methods: Experimental study design was used on 20 cats (males and females) randomly divided into two equal groups (A and B). Ketamine (10 mg/kg i. m.) was administered to group A in the morning. The same procedure was repeated using different dosages (15 mg/kg and 20 mg/kg i.m.) at intervals of 3 days each. A similar procedure was applied to group B in the evening. A week after, diazepam (1.5 mg/kg, 2.5 mg/kg and 3.5 mg/kg i. v.) were administered to group A and B using the same procedure used in ketamine administration. All baseline measurements were recorded after each drug administration and were repeated at 15, 30, 45, 60, 75, 90, 105, and 120 min intervals after induction of anesthesia with ketamine and diazepam.Results: It was found that the onset of action of ketamine following i. m. administration was slightly longer at evening (2-5 mins) while that of diazepam was instant after i. v. administration. The duration of recumbency was shorter in the morning using ketamine while longer following diazepam (7-19 mins) administration. The rectal temperature, respiratory and pulse rate were lower in the morning following ketamine and diazepam administration even though, the respiratory and pulse rate decreases as the dose was increased but not statistically significant. The duration of action and recovery was significantly longer in the morning after ketamine and diazepam administration.Conclusion: According to this study, there was not much difference between morning and evening administration using both drugs. However, it should be noted that influence of time of administration was evident in some of the parameters measured especially with diazepam.Â

Stability analysis and vibration control of a class of negative imaginary systems

This paper presents stability analysis and vibration control of a class of negative imaginary systems. A flexible manipulator that moves in a horizontal plane is considered and is modelled using the finite element method. The system with two poles at the origin is shown to possess negative imaginary properties. Subsequently, an integral resonant controller (IRC) which is a strictly negative imaginary controller is designed for the position and vibration control of the system. Using the IRC, the closed-loop system is observed to be internally stable and simuation results show that satisfactory hub angle response is achieved. Furthermore, vibration magnitudes at the resonance modes are suppressed by 48 dB

A PD-type fuzzy logic control approach for vibration control of a single-link flexible manipulator

This paper presents the design of PD-type fuzzy logic controller (PDFLC) for vibration control of a single-link flexible manipulator system. A flexible manipulator system is a SIMO system with motor torque as the applied input and the hub angle and tip deflection as its two outputs. The system is modelled using the finite element method. The PDFLC have two inputs, the hub angle error and its derivatives, the output of the controller is fed to the flexible manipulator model as the control signal which successfully suppressed the vibration and achieved a precise tip deflection at the tip end. The tracking performance and robustness due to payload variation were investigated via simulation in Simulink. The Simulation results show that the PDFLC provides a robust control to both internal and external disturbances

Vibration and tip deflection control of a single-link flexible manipulator

In this paper, a hybrid control scheme for vibration and tip deflection control of a single link flexible manipulator system is presented. The purpose of this control is for input tracking, vibration control of hub angle and tip deflection control. The control scheme consists of a resonant controller and a fuzzy logic controller (FLC).The resonant controller is used as the inner loop feedback controller for vibration control using the resonant frequencies at different resonant modes of the system which were determined from experiment. The fuzzy logic controller is designed as the outer loop feedback controller for the tracking control and to achieve zero steady state error. The performance of the proposed control scheme is investigated via simulations and the results show the effectiveness of the control scheme, in addition the controller is tested to show it robustness using different values of payload

Comparing the performance of sway control using ZV input shaper and LQR on gantry cranes

This paper presents the investigation into the performance of ZV input shaper and LQR for sway control of a non linear gantry crane systems. The non linear model of the system was derived using the Lagrangian energy equation and then linearized using Taylor's series expansion. ZV input shaper was proposed using the estimated natural frequency and damping ratio of the system. LQR was also designed by selecting appropriate performance index to the system. Performances of the controllers are assesses based on time response specifications and level of oscillation reduction. MATLAB simulation results of the system subjected to a pulse input torque shows that LQR was more effective and reliabl

Payload swing control of a tower crane using a neural network–based input shaper

This paper proposes an input shaping technique for efficient payload swing control of a tower crane with cable length variations. Artificial neural network is utilized to design a zero vibration derivative shaper that can be updated according to different cable lengths as the natural frequency and damping ratio of the system changes. Unlike the conventional input shapers that are designed based on a fixed frequency, the proposed technique can predict and update the optimal shaper parameters according to the new cable length and natural frequency. Performance of the proposed technique is evaluated by conducting experiments on a laboratory tower crane with cable length variations and under simultaneous tangential and radial crane motions. The shaper is shown to be robust and provides low payload oscillation with up to 40% variations in the natural frequency. With a 40% decrease in the natural frequency, the superiority of the artificial neural network–zero vibration derivative shaper is confirmed by achieving at least a 50% reduction in the overall and residual payload oscillations when compared to the robust zero vibration derivative and extra insensitive shapers designed based on the average operating frequency. It is envisaged that the proposed shaper can be further utilized for control of tower cranes with more parameter uncertainties

Sensorless position control of DC motor using model predictive controller

Sensors like rotary encoders are widely used in measuring the speed and position of DC motor in applications. Due to expensiveness, calibration complexities of these type of encoders, sensorless methods for measurements were used alternatively. This paper presents sensorless position control of a wheeled DC motor using system identified model. This approach overcome some conventional sensorless techniques that uses some approximations. The model is developed using black box identification scheme, based on the identified model, a model predictive controller was designed to track a desired horizontal position of the wheel. Practical experiment shows the concept gives a very good estimation of the position and speed and can be used in control application

LMI-based state feedback controller design for vibration control of a negative imaginary system

This paper presents state feedback control via linear matrix inequality (LMI) for vibration control of a flexible link manipulator (FLM) system. FLM is a negative imaginary (NI) system with high amplitude vibration and oscillation. In this work, pole placement controller (PPC) which is NI controller is used to control the FLM vibration, to achieve a precise hub angle positioning with minimum tip deflection. A decay rate is introduced to improve the speed of the system and investigate the effect on the system performance. LMI optimization technique is used to obtain the optimal and best control gains of PPC using Matlab LMI toolbox with different values of the decay rate. Simulation results show that satisfactory hub angle and tip deflection responses are achieved using the proposed controller. Damping is successfully added into the system and reduces the system vibration at the first two vibration modes by 40 dB. Hub angle positioning is achieved with minimum tip deflection by changing the value of decay rate

Adaptive input shaping for sway control of 3D crane using a pole-zero cancellation method

This paper presents an adaptive input shaping based on pole-zero cancellation (APZC) technique to suppress load sway of a crane system. In this method, a reference system is selected and the proposed adaptive shaper is made to force the actual system to adapt to the changes in natural frequency and damping ratio as the cable length increases or decreases. Simulation results are compared with a zero vibration derivative input shaper designed based on average travel length (ATL) to investigate the performance of the proposed shaper. Simulation using three cable length of 0.7 m, 0.5 m and 0.3 m shows that APZC gives better payload sway reduction with smallest maximum swa