57 research outputs found
Design and Implementation of a Mobile Robot
A robot is a mechanical device, which possesses the capability of emulating a
human's characteristic in some way or another. The project is to build a mobile
robot, which should be able to avoid any encumbrances, while at the same time, is
capable of maneuvering at a predetermined path. The mobile robot should be
intelligent enough to make decisions as to which direction it is to turn when it
reaches a certain situation - ie. a turning point, a T-junction, a dead end, etc. An
extensive research would be conducted first before starting offdesigning the robot.
Subsequently, the exact materials would be selected. The structure of the mobile
robot would then be designed and built. The main circuitries required to construct a
mobile robot include ultrasonic sensors, a pair of H-bridge circuits, and a
microcontroller circuit. The ultrasonic sensors serve as eyes for the robot. They help
to detect obstacles en route. The purpose of constructing the H-bridge circuit is to
control the rotational direction of the motors. The microcontroller plays a most
essential role in the mobile robot. The microcontroller acts as a brain for the mobile
robot and would be making decisions on how the robot should react when it
encounter obstacles. Due to itssimplicity and the ease in getting familiarized with, an
8-bit PIC16F84A microcontroller is implemented for the project. The components -
that is, the sensors, motors, the H-bridge circuits, and the microcontroller, would be
validated individually first, before integrating them onto the mobile robot. The
program of the microcontroller would be written in assembly code form and would
then be validated. Lastly, successive validation tests would be conducted on the
entirerobot to ensurethe reliability ofthe mobilerobot
Design and Implementation of a Mobile Robot
A robot is a mechanical device, which possesses the capability of emulating a
human's characteristic in some way or another. The project is to build a mobile
robot, which should be able to avoid any encumbrances, while at the same time, is
capable of maneuvering at a predetermined path. The mobile robot should be
intelligent enough to make decisions as to which direction it is to turn when it
reaches a certain situation - ie. a turning point, a T-junction, a dead end, etc. An
extensive research would be conducted first before starting offdesigning the robot.
Subsequently, the exact materials would be selected. The structure of the mobile
robot would then be designed and built. The main circuitries required to construct a
mobile robot include ultrasonic sensors, a pair of H-bridge circuits, and a
microcontroller circuit. The ultrasonic sensors serve as eyes for the robot. They help
to detect obstacles en route. The purpose of constructing the H-bridge circuit is to
control the rotational direction of the motors. The microcontroller plays a most
essential role in the mobile robot. The microcontroller acts as a brain for the mobile
robot and would be making decisions on how the robot should react when it
encounter obstacles. Due to itssimplicity and the ease in getting familiarized with, an
8-bit PIC16F84A microcontroller is implemented for the project. The components -
that is, the sensors, motors, the H-bridge circuits, and the microcontroller, would be
validated individually first, before integrating them onto the mobile robot. The
program of the microcontroller would be written in assembly code form and would
then be validated. Lastly, successive validation tests would be conducted on the
entirerobot to ensurethe reliability ofthe mobilerobot
Development of a path tracking system for GPS denied environment
Navigation applications such as Google Maps and Waze fail to function at global positioning system (GPS) denied environments. This is typically the primary problem faced by mountain hikers who have lost their way in a dense forest or a dementia patient who has lost his/her way. Navigation applications fail to function at places without internet signal. Also, a dementia patient may not be able to recall his original destination, rendering the GPS useless.The development of a path tracking system which does not rely on GPS is therefore necessary in such a situation. The system should be capable of guiding a person to return back to his/her original starting point without the requirement of a GPS. In this paper, we present the development of a path tracking system which exploits the inertial measurement unit embedded in a mobile phone. Doing so, the use of the GPS can be evaded. The system that we have developed consists of 3 main functions, i.e. (i) path recording, (ii) path navigation, and (iii) map generation. An SQLite database is setup in this application for storing data. Java libraries such as GraphView and Canvas are implemented to perform observation on the data obtained from the sensors and also to map the route according to the data stored into the device. The validation results show that the accurac
Characterization of a 0.14 μm Submicron NMOS with Silvaco TCAD Simulator
A 0.14 μm NMOS was simulated using ATHENA and ATLAS modules from TCAD simulator. The electrical characteristics of the submicron device were studied. Constant field scaling was applied to the following parameters: the effective channel length, the density of the ion implantation for threshold voltage (VTH) adjustment, and the gate oxide thickness (TOX). Additional techniques implemented to avoid short channel effects in submicron devices were shallow trench isolation (STI), sidewall spacer deposition, lightly doped drain (LDD) implantation, and retrograde well implantation. The results show that retrograde well implantation allowed the highest density of the dopant to fall below the surface of the substrate. With the application of sidewall spacer and LDD implantation, a lighter doped region was created beyond the n+ drain/source junction. As the layers of metallization increases, it was observed that drain current (ID) increased as well. The important parameters for NMOS were measured and validated
Fabrication and characterization of a 0.14 μm CMOS device using ATHENA and ATLAS simulators
A 0.14 µm CMOS transistor with two levels of interconnection was designed and simulated to investigate its functionality and characteristics. ATHENA and ATLAS simulators were used to simulate the fabrication process and to validate the electrical characteristics, respectively. A scaling factor of 0.93 was applied to a 0.13 µm CMOS. The parameters being scaled are the effective channel length, the density of ion implantation for threshold voltage (Vth) adjustment, and the gate oxide thickness. In order to minimize high field effects, the following additional techniques were implemented: shallow trench isolation, sidewall spacer deposition, silicide formation, lightly doped drain implantation, and retrograde well implantation. The results show that drain current (ID) increases as the levels of interconnection increases. The important parameters for NMOS and PMOS were measured. For NMOS, the gate length (Lg) is 0.133 µm, Vth is 0.343138 V, and the gate oxide thickness (Tox) is 3.46138 nm. For PMOS, Lg is 0.133 µm, Vth is −0.378108 V, and Tox is 3.46167 nm. These parameters were validated and the device was proven to be operational
- …