Wan Zuha Wan Hasan

Pressure Sensor: State of the Art, Design, and Application for Robotic Hand

We survey the state of the art in a variety of force sensors for designing and application of robotic hand. Most of the force sensors are examined based on tactile sensing. For a decade, many papers have widely discussed various sensor technologies and transducer methods which are based on microelectromechanical system (MEMS) and silicon used for improving the accuracy and performance measurement of tactile sensing capabilities especially for robotic hand applications. We found that transducers and materials such as piezoresistive and polymer, respectively, are used in order to improve the sensing sensitivity for grasping mechanisms in future. This predicted growth in such applications will explode into high risk tasks which requires very precise purposes. It shows considerable potential and significant levels of research attention.

Non-Linearity in Wide Dynamic Range CMOS Image Sensors Utilizing a Partial Charge Transfer Technique

The partial charge transfer technique can expand the dynamic range of a CMOS image sensor by synthesizing two types of signal, namely the long and short accumulation time signals. However the short accumulation time signal obtained from partial transfer operation suffers of non-linearity with respect to the incident light. In this paper, an analysis of the non-linearity in partial charge transfer technique has been carried, and the relationship between dynamic range and the non-linearity is studied. The results show that the non-linearity is caused by two factors, namely the current diffusion, which has an exponential relation with the potential barrier, and the initial condition of photodiodes in which it shows that the error in the high illumination region increases as the ratio of the long to the short accumulation time raises. Moreover, the increment of the saturation level of photodiodes also increases the error in the high illumination region.

A sensitivity study of piezoresistive pressure sensor for robotic hand

In this paper, we have studied and surveyed the field of robotic hand and the works that have been done in this area related to types of materials such as piezoresistive, piezoelectric and capacitive as well as a few types of pressure sensors. It indicates that piezoresistive pressure sensor is the best technique that can be used to implement a robotic hand for pick and place application. An adequate experiment of pressure sensor interfacing and calibration have been done in this paper. As a preliminary result of the works, output voltage (V) of the pressure sensor versus applied force input (N) are presented. Furthermore, this framework can be used to derive a new approach of pressure sensor distribution on the robotic hand based on complex algorithm of controlling applied pressures.

Alternative Solar-Battery Charge Controller to Improve System Efficiency

When the heat losses sense is adopted for some solar system and power conversion components in residential building application, it is benefit to use those losses, that are consequently acts inversely on system efficiency, as a useful energy to modify the performance of that system instead of dissipated. In terms of efficiency of solar-battery charge controller, power dissipation is always associated with every power component and the losses would be either results from switching and conducting components or from the OFF state of the main switching component. This paper proposed a high efficiency solar-battery charge controller as an alternative to the main solar charge controller in most conventional residential solar system , the concept of the proposed controller circuit based on using the off state energy duration as well as that power losses coming from the main switching component and complexity of the conventional controller, and using this energy in a separate current path to energize an auxiliary battery or directly load used to cool or even to ventilate the system components causing in improving its performance. This will leads to electronic circuit with low losses as a compared with the conventional charge controller to be a part of the integrated and automated building solar system, the design has an algorithm based on some environment parameters like sun Irradiance and weather temperature, this algorithm seems to be inversely calculated because its start from the value of full charge battery voltage. A Simulink Matlab simulator is attempted in the simulation phase of this research as well as an experimental data has been collected to verify the circuit function and energy saving goal.

GPS based portable dual-axis solar tracking system using astronomical equation

The overall objective of this study is to design and develop a portable dual-axis solar tracking system that focuses on portable and mobility purpose. This paper discusses the design, electronic control system and the algorithm based on the astronomical equation. The tracking system utilizes the GPS module and a digital compass sensor for determining the location and the heading feedback of the system respectively. Moreover, the microcontroller based tracking system is embedded with a PID controller for which will increase the PV positioning accuracy based from the feedback signal of the absolute encoder. Furthermore, this paper also analyses and compares the performance between the fixed-tilted PV panel and the developed portable solar tracking system.

Flexible bio-signals channels acquisition system for ECG and EMG application

Each nerves and muscles of human body will generate potentials, voltages, and electrical field strength and known as bio signals such as electrocardiograph (ECG), electromyography (EMG), electroencephalogram (EEG), and electrooculogram (EOG). The signals may be acquired through non-invasive surface Ag/Ag Cl applications although the generated signals exist in very low levels of voltages. All the bio signals may be obtained from basic designs of instrumentation amplifier with the help of Ag/Ag Cl electrodes. However, different frequency band, interference, amplitude and strength may give huge challenges to the acquisition system. This paper provides instrumentation amplification design, include with the design concept to allow for flexible channels. There are lots of advantages from the proposed design such as minimal additional cost for additional channels used and circuit design modification or replacement. To suits bio-signals frequency bandwidth need, digital filter design in Labview software is added, as a part of acquisition system and to discard unwanted signals outside frequency bandwidth.. For now, the design is able to demonstrate to acquire two bio-potentials signals; ECG and EMG signals.

A wireless flipper robot using interface free controller

Robots have been developed by human to do various things to make our life easier. There are many approaches, systems and technologies can be applied to develop different types of robots depended on the usage. This paper presents the new approach of interfacing a wireless robot using IFC (Interface Free Controller). This controller offers a new concept of microcontroller embedded system developed for robotic application. IFC is an interfacing hardware and it configures the peripherals. This flipper robot is a fighting robot which previously participated in the robot war game. The complete design, interfacing, robot constructions, specification of the robot and testing processes are detailed out.

Fault Detection with Optimum March Test Algorithm

Integrating a large number of embedded memories in System-on-Chips (SoCs) occupies up to more than 70% of the die size, thus requiring Built-In Self-Test (BIST) with the smallest possible area overhead. This paper analyzes MATS++(6N), March C-(10N), March SR(14N), and March CL(12N) test algorithms and shows that they cannot detect either Write Disturb Faults (WDFs) or Deceptive Read Destructive Faults (DRDFs) or both. Therefore to improve fault detection, an automation program is developed based on sequence operation (SQ) generation rules. However after solving the undetected fault, the outcome in term of its detection result of Static Double Cell Faults using the specified test algorithm especially Transition Coupling Faults (CFtrs), Write Destructive Coupling Faults (CFwds), Read Destructive Coupling Faults (CFrds) and Deceptive Read Destructive Faults (CFdrds) are observed.

Pattern investigation for landfill of methane gas concentration measurement

One of the most important actual problems in the gas detection field is that there are strong demands for gas methane source detection to prevent explosions or poisoning accidents …etc. In this case we need an autonomous equipment to perform wide surveying of the ground area surface based on a pattern to know its concentration on each spot of the required ground area. The best method of performing this task is to use autonomous quadcopter with high flexibility which do not affect by risk of this gas and the rough and irregular ground surface and perform the task with high speed and lower cost. This paper presents a simulation comparison of search pattern types properties and practical methane gas concentration measurement.

On the performance of a polycrystalline PV panel under different impulse voltages and temperatures

Lightning events are one of the factors that affect performance of a solar power system either by direct or indirect strikes. When lightning strikes directly to a panel, it can affect function and life cycle of the panel. Therefore, considering the electrical performance characteristics such as open-circuit voltage, short-circuit current, and maximum power of the solar panels under high voltage conditions is an important issue. In this paper, the effect of impulse voltage on the change of electrical behaviour of a polycrystalline solar panel is studied. The experimental platform is tested by a lightning impulse generated over a range of 100 kV to 300 kV. The results revealed that as the lightning impulse voltage is increased, the maximum power output gradually decreases. The performance of percentage difference from normal between 100 kV to 300 kV increased to 10.02 % for the maximum power output and the graph showed an increasing non-linear trend. After testing with lightning impulse voltages, the electrical performance of the solar panel under different thermal conditions (temperature) was evaluated in the range of 25 °C to 70 °C and the results are discussed accordingly. When the different temperatures were applied, efficiency of the polycrystalline panel continuously degraded. The percentage difference of the maximum power between samples of 100 kV to 300 kV at 70 °C increased from 2.09 % to 7.11 %.