Sharif Digital Repository

From the creation of the first robots, researchers have been fascinated by the possibility of interaction between a robot and its environment, by the possibility of robots interacting with each other and with humans. The common, underlying assumption is that humans prefer to interact with machines in the same way that they interact with other people. In this work, an assistant robot is developed based on a commercial platform, known as Alice R-50 (with the Iranian name of Mina). Alice is designed specifically for human-robot social interaction and has been used widely for studies on developmental and social robotics. It is used to improve and encourage the development of communication and... 

It is so essential to study a safe dynamics of agricultural mechanical equipment during duty stroke, plus getting a rich information about the nature of the soil under processing and in many cases there are associated simultaneous problems, so the main aim of this study is to create a safe working conditions for such specific equipment to extend their life time span as possible as it could. This study will predict an un-usual working circumstances for agricultural tools including plough of course depending on some automated technologies with fast response supported by smooth working conditions. Simply, the proposed Investigative system consists of a linear potentiometric element with... 

In the recent years, development of new technologies in the field of cognitive science has made a huge effect on the people social life style. Facial expression imitation with applications in the design of human robot interaction (HRI) systems is an active area of research. In this study, we propose an approach using a humanoid social robot, The Alice, for real-time imitation of human facial expression. The facial keypoints of the user are extracted by using the Kinect sensor together with manipulated SDK 2.0 codes. Kinect output array are collected for each expression, then the training dataset is created with these output arrays. An accurate Artificial neural network (ANN), which has a... 

Minimally invasive surgery (MIS) is a new surgical technique in which surgery is performed using smart instruments and viewing apparatus inserted through a very small incision rather than by making a large incision to expose, and afford access to the operation site. Piezo film force sensor can be used in MIS graspers for providing tactile data to overcome problems such as lack of sense of touch or to find hidden arteries.This thesis, investigates fundamental understanding of piezo film sensor especially when we want to connect these sensors to measurement units.Two different approaches for signal conditioning the sensor have been proposed and circuits have been fabricated. Several... 

In the first part of the thesis, we introduce the structure of a Nano-Newton CMOS-MEMS capacitive force sensor. This force sensor has been utilized out-of-plane sensing mechanism with high accuracy and reliability. Also, we discuss about sensitivity analysis of this force sensor. The largest change of capacitance (increased capacitance + decreased capacitance) occurs in ℓ=2/3. Sensitivity for increased capacitance grows by 8.33% and for decreased capacitance grows by 2.27%. The proposed method provides useful guidelines to increase the sensitivity of the sensor up to 250%. In the second part, a fixed structure controller, PID type, is proposed to control and suppress the in-plane vibration... 

Over the last decades the attention of the most modern countries about usage of wind has grown due to the recent crisis of energy. This renewable energy source offers a cost effective solution for electricity production. Wind energy is the best candidate among other sources due to wind turbines technology reliability. In order to gain maximum power from wind turbines, their size becomes relatively large, which creates more complexity in their repair and maintenance, furthermore Wind turbine downtime is outside the expectations, which is more costly than corrective maintenance, therefore in order to minimize sudden downtimes and related huge maintenance, a reliable monitoring technique must... 

Pipeline systems have a major role in civil infrastructure for transportation of energy sources including, petroleum, natural gas, and water. As most pipelines are located in hard-access location such as underground and sea as well as mountains, they are vulnerable to corrosion, cracks and thus, unpredictable failure. Failure of pipelines not only costs millions of dollars but also causes environmental damage, requiring continuous health monitoring systems to provide early detection and early warning of flaws such as corrosion and leaks. Structural health monitoring based on ultrasonic guided waves is used in structures as plates, composites, rods, piping and tubing. This research aims to... 

This research focuses on the robust mobile robot localization exploiting motion information acquired from an optical mouse operating based on optical flow technology. Most techniques of visual motion measurement are based on the well research discipline called “optical flow”. Theoretically, optical flow as a method of localization can be highly accurate, but it is sensitive to the noise and surface texture/optical characteristics and distance variations between the CCD detector and surface. As one could not achieve acceptable results in practical situations, to handle these problems, we propose to attach an acceleration – gyro (INS) sensor on the CCD detector (optical mouse) to improve the... 

The main objective of this project is to investigate modeling for a robotic swarm with suitable sensors and to analyze effect of sensory noise on the control and unity of the swarm. This project is an extension of analytical study done by S. Etemadi, A. Alasty and G. Vossoughi in Sharif University of technology. The flocking frame assumed to have a leader robot that controls over all behavior of the swarm made of agents’ robots with limited equipments and low intelligence that only obey some basic attraction and repulsion laws that will be explained. As an initial step of the analysis, we investigate proper physical model, sensors and navigation systems suitable to the model. Next, the... 

Large-size buried pipelines are an efficient way of transporting of water, waste water, sewage, gas, and oil resources in across the world. Since the buried pipe lines are exposed to many unexpected conditions, such as landslides, corrosion, fatigue, unexpected loading, earthquakes, material flaws or even intentional damaging, so the inspection requirements lead to adoption of new method of maintenance, protection and conserving of pipelines. This proposed project aims to improve the trustworthiness, reliable, yet economical technologies for monitoring of behavior of buried pipe lines during operation and assessing the risk of pipe lines failure. Piezoelectric sensor is bonded on the surface... 

Minimally Invasive Surgery (MIS) is a modern surgical technique in which the operation is performed through small incisions in the body. Therefore, the surgeon looses his/her sense of touch which is of high importance in any medical operation. In the present work, a novel smart grasper is presented in which the surgeon can virtually acquire a feeling of force/momentum experienced by the organ/tissue. The smart grasper uses piezoelectric sensors bonded at desired locations to detect the applied force/momentum applied by surgeon and to measure the transmitted force/momentum to the tissue/organ. First, an accurate electro-mechanical model of the smart grasper is developed and the relations... 

An isopropanol supercritical reducing environment was prepared by fabricating a high temperature, high pressure autoclave, in order to make a hybridized structure of zinc oxide and graphene oxide, entitled as ZnO-G. In this novel structure, the oxygen acts as bridging element between zinc and carbon, that connects a wide band gap semiconductor to a narrow banded one. The hybridization mechanism is studied by FTIR analysis, and morphology is shown by FE-SEM. The micrographs obtained from the thin film show a stacked pile of ZnO-G disks, like a button, dispersed on a crack free layer. In addition, the crystallographic structure was revealed by comparing low angle X-ray diffraction patterns to... 

Wireless Sensor Networks (WSNs) consist of sensor nodes that are connected to each other and are widely used in many applications to acquire and process information. WSN nodes are battery powered, therefore energy management is a key factor for long live network. Node radio transceiver unit uses the most part of energy resource of the node and as a result limits the network lifetime. One way to prolong lifetime of network is to utilize routing protocols to manage energy consumption. To have an energy efficient protocol, we can apply cluster organization on the network, where sensor nodes are partitioned into groups called cluster. Then, the whole cluster data is sent through Cluster Head... 

Electrochemical sensing of glucose has received paramount attention in recent years, particularly, the non-enzymatic glucose sensing is one of the trends in the whole biosensing world. In this research, synthesis and evaluation of a hybrid structure of vertical oriented nickel nanorod-reduced graphene oxide sheets as a non-enzymatic glucose sensor were performed. The 3D array of nickel nanorods was synthesized by electrodeposition of nickel sulfate electrolyte in track-etched polycarbonate template with 100 nm pore size and 6-10 μm thickness. The electrodeposition performed in various conditions, and the best result was achieved by application of potential of 3 V for 60 minutes. The shiny... 

Hydrogen sulfide, H2S, is a toxic gas and has detrimental effects on human health and the oil and gas industry. Therefore, its identification is very important. According to the devastating effects of this gas, then, the general mechanisms have been studied for gas detection. In addition, by highlighting the benefits of the multilayer nanostructure electrochemical sensors, an applicable and efficient method for the industrial production of these sensors has been investigated. In this regard, the sol-gel method is used to prepare the SnO2-CuO multilayer thin film and the advantages of this method was compared to PVD method. Also sensor properties of both deposition methods have been... 

This research describes a new and relatively general method to grow well-aligned carbon nanotubes (CNTs) on cobalt-deposited stainless steel by thermal chemical vapor deposition (CVD) of ethylenediamine precursor. The CNTs are vertically aligned at high density over large areas on the surface. Different effective parameters in growth of carbon nanotubes, as type of substrate, surface treatment, temperature of growth , feeding carbon supplies have been studied. Finally, aligned carbon nanotubes have been prepared by 100-150 nm diameter and 9µ length. CoOx•nH2O–MWCNTs nanocomposites were successfully synthesized, using a cathodic electrochemical reduction of H2O2 to deposit cobalt... 

Few years ago, when people were talking about image sensors, the minds were automatically focusing on the pictures and photos that were/are taken for recording the memories. Nowadays, however, image sensors have prominent and unbelievable role in different aspects of our life, which "image" is only representing part of this role. A wide variety of applications image sensors can be enumerated such as, Scientific, security, medical, machine vision, ITs, biometrics, automotive, etc. To evaluate the quality of an image sensor, there are different parameters, from the dynamic range, high resolution and suitable speed to low noise, low power consumption and other parameters. The art of companies... 

Pipelines are the preferred means for transporting of liquid or gas phase materials. The economy of many countries is extremely dependent upon a large network of pipelines systems to transport and distribute the nation’s energy resources. Damages to the pipe structure may cause leakage and result in economic losses or even loss of life. Developing methods for detecting the anomalies and damages to the structure before they lead to catastrophic events is vital. Multiple pipeline misadventures over the past several years have resulted in hundreds of fatalities and billions of dollars in property damages. These accidents demonstrate that the current monitoring methods are not sufficient... 

In this research non-contact ultrasonic based method is used for liquid level measurement in a container. A system has been designed and developed to determine the liquid level and show the results on a personal computer. The system contains three main parts, which are mechanical and electronic parts and the programming. The setup can measure the liquid level with the accuracy of 1cm. An ATMEGA8 microprocessor commands to relays and controls the pumps. The pumps are used to change the height of the liquid in the containers to accurately calibrate the sensor and test its operation. The ultrasonic sensor, which is mounted above the vessel, transfers the data to an ATMEGA64 microprocessor for... 

The fire event may cause danger to life and property. In general, most fire-detection devices are set on the wall or ceiling. . However, this method is not flexible enough to detect a fire occurrence, and this needs the use of many fire-detection devices in a building. Since it is not suitable, we use an active fire-detection device to detect a fire incident. In the past, smoke sensors were used for fire detection, but often the smoke sensors triggered a false alarm when someone smoked in the room. Therefore, multisensor fire-detection methods are one of the current important developments for fire- detection technology. We design a fire-detection module using an ionization smoke sensor...