Dirman Hanafi

PID Controller Design for Semi-active Car Suspension Based on Model from Intelligent System Identification

This paper presents a new method to design a semi-active suspension system. A semi-active suspension is developed by installing a variable shock absorber parallel with the passive suspension system and controlled using PID controller. A high fidelity mathematical model for capturing the realistic dynamic of car passive suspension system for the basic element of the semi-active suspension system is determined using the intelligent system identification. The car passive suspension system is assumed to have NARX model. The result shows that the response of the semi-active suspension system can follow the input signal, it means the PID controller is successfully control the variable shock absorber in order eliminate the road surface disturbances effect to the car body.

Heat exchanger's shell and tube modeling for intelligent control design

The shell and tube of heat exchanger is a medium where heat transfer process occurred. The accuracy of the heat exchanger depends on the performance of both elements. Therefore, both components need to be controlled in order to achieve a substantial result in the process. For this purpose, the actual dynamics of both shell and tube of the heat exchanger is crucial. This paper discusses two methods used in deriving the mathematical modeling of the system. First, physical dynamic modeling is obtained using physics and dynamics laws where actual parameters of the shell and tube are considered. Secondly, the model is determined by applying non-parametric system identification based on experimental response on the heat exchanger. Two models are used to design the shell and tube intelligent control. The intelligent control type is a Fuzzy Proportional Derivative (FPD) control. The experiment results shows that the shell and tube heat exchanger model develop using its physical parameters and controlled with FPD controller give better response, it means it can used as a model and controller of the shell and tube heat exchanger.

Current source with low voltage controlled for surface Electrical Stimulation

Functional Electrical Stimulation (FES) is a promising way to restore mobility to Spinal Cord Injury (SCI) patients by applying low-level electrical current to the paralyzed muscles so as to enhance that persons ability to function and live independently. However, due to the limited number of commercially available FES assisted exerciser systems and their rather high cost, the conventional devices are unaffordable for most peoples. Thus, this paper makes a comparative study of the various design of a multiple purpose portable functional electrical stimulator which is used in surface stimulation for patients with spinal cord injuries. The functionality, circuit performance and reliability of the circuits are presented.

Mathematical Modeling of Industrial Heat Exchanger System

In manufacturing and industrial fields used heat exchanger to control of temperature weather as a boiler or cooling system. This system is not stable as the temperature output can easily disturb by noise and other disturbance such as surrounding temperature. To improve the heat exchanger system performance, the mathematical model‘s needed. The heat exchanger mathematical model in this case is constructed using dynamic modelling based on real parameters of the heat exchanger. The simulation result shows almost similar trend of responses with the experiment result, it means they are can used as a model of the heat exchanger.

Two-degree-of-freedom robust control for a non-minimum phase electro-hydraulic system

Electro-hydraulic actuator (EHA) system inherently suffers from uncertainties, nonlinearities and time-varying in its model parameters which makes the modeling and controller designs are more complicated. The main objective of this paper is to perform a robust control design using discrete-time sliding mode control (DSMC) with two-degree-of-freedom control strategy. The proposed controller consists of feedback and feedforward combination which capable to reduce phase lag during the trajectory tracking of EHA system. The feedforward controller is developed by implementing the zero phase error tracking control (ZPETC) technique which the main difficulty arises from the nonminimum phase system with no stable inverse. Finally, a chaotic trajectory tracking is performed in the experimental works to show the robustness of DSMC controller and performance comparison is made with Linear-Quadratic-Regulator (LQR) and Proportional-Integral-Derivative (PID) controllers. The findings show that the proposed controller with ZPETC outperforms the LQR and PID controllers in terms of tracking accuracy.

Intelligent system identification for an axis of car passive suspension system using real data

This paper presents an intelligent system identification using multilayer perceptron neural network algorithm for an axis car passive suspension model. Nonlinear AutoRegressive with eXogenous input (NARX) model were assumed for the system in order to determine the multilayer perceptron neural network structure. The intelligent system identifcation contructed for NARX model used real input output data acquired by driving a car on a special road event. The results show that the method proposed is suitable for modeling a quarter car passive suspension systems.

The quarter car fuzzy controller design based on model from intelligent system identification

In this paper, the design of the quarter car fuzzy logic control (FLC) for passive suspension model has been done. The quarter car model is identified using intelligent system identification and assumed has NARX model. The car input output data are collected in experiment by driving car on special road event. The result shows that the fuzzy logic controller is suitable for eliminating road surface disturbances to the suspension system.

Development of hand exoskeleton for rehabilitation of post-stroke patient

Degenerative muscle diseases characterized by loss of strength in human hand significantly affect the physical of affected individuals. A soft assistive exoskeleton glove is designed to help post-stroke patient with their rehabilitation process. The glove uses soft bending actuator which has a rubber like tender characteristic. Due to its rubber like characteristic, flexion of finger can be achieved easily through pneumatic air without considering other hand motions. The application involves a post-stroke patient to wear the soft exoskeleton glove on his paralyzed hand and control the actuation of the glove by using pneumatic air source. The fabrication of the soft bending actuator involves silicone rubber Mold Star® 15 SLOW which falls within the soft category of shore A hardness scale. The soft bending actuator is controlled by Arduino Mega 2560 as main controller board and relay module is used to trigger the 3/2-way single solenoid valve by switching on the 24VDC power supply. The actuation of the soft...

Preliminary approach of FES-cycling framework model development for spinal cord injury application: Part 1

Since 1960s, functional electrical stimulation (FES) applications has been used to improves, recover and restore several functions of paralyzed muscles due to spinal cord injury (SCI), stroke and any level of injury related to spinal. FES induced movement control is a significantly challenging area due to complexity and nonlinearity of musculoskeletal system which is the complexity control of muscle motor function model by the artificial activation of paralyzed muscles. Lots of research interest in lower-limb model especially for paraplegia either by exo-skeleton, gaiting exercise, robotics assistive device, wheel-chair, cycling, rowing and etc. Thus, in part one (1) of this paper discussed surface issues of several relations between software and hardware development via FES-Cycling framework model. Simple and efficient approach by using model-based design for experimental process and data gathering. The computer-based closed-loop FES-ScienceMode Hasomed-GmbH system uses MATLAB/Simulink, Software Development Kit 7.1 and RealTime Windows Target under Windows 7 for online data acquisition via microcontroller based, controlling and processing. Proposed optimization fuzzy control-strategy about FES-Cycling induced performance simulation studies against muscle fatigue and external disturbances with customized musculoskeletal mechanism lower limb model for cycling applied and majorly about result and discussions will be highlight in part two (2) for upcoming publications.

Preliminary study of functional electrical stimulation: Application of swinging trajectory based on knee-joint range-of-motion (ROM)

Nowadays, research and developments of control system for spinal cord injury (SCI) using functional electrical stimulation (FES) is widely used. Restoring mobility to persons with paraplegia with regard to FES-approaches for function restoration is really challenging issues. A sarcastic view of FES is the complexity control of muscle motor function by the artificial activation of paralyzed muscles. Therefore; laboratory apparatus setup to study the knee joint control by FES electrical stimulation test with computer-controlled stimulator system consisted of Matlab/Simulink-Hasomed has been arranged. Anthropometric measurements of length of the lower limb were made. Novel wearable lower limb suit developed for FES experimental. This scenario can be seen by monitoring the sinusoidal stimulation current range muscle contraction on able-bodied (AB) subject with the simulation work was applied on knee joint swinging trajectory range-of-motion. Significant value of sinusoidal stimulation current signal is determined and regulated to vary within potential of preliminary data mining attempts to model an efficient power consume of knee joint controller. At this stage, it can improve with better technique by reduce and determine overall parameter limitation using FES.