CHAPTER 1 INTRODUCTION 1.1 BACKGROUND In twenty first

CHAPTER 1

INTRODUCTION

1.1       BACKGROUND

In twenty first century, there are numerous researches toward the Autonomous System in vehicle. The autonomous system criteria are able to localize its position, model the given environment and plan a path by itself to the desired location. The most used Navigation System for a vehicle is Global Positioning System (GPS). GPS use four satellites to locate a receiver using microwaves but when there are walls or roofs or other thick material, it was attenuated and scattered, then the signal will become distract and lost. There should be another navigation system to provide navigation support under roofed area and encounter the deficiency of GPS which is also called Indoor Navigation System (INS).

Indoor navigation system (INS) is any system which attempts to provide an accurate positioning inside of a covered structure.1 According to Gothivarekar, among all technologies for navigation system, the most famous is GPS, but it only effective at uncovered structure.2 The GPS use four satellites to locate a receiver using microwaves but when there are walls or roofs or other thick material, it were attenuated and scattered, then the signal will become distract and lost. Thus, INS was developed to encounter the deficiency of GPS.

The INS for unmanned vehicle works in indoor environment by locates itself from the previous position and from the controller. The INS also should able to map the unknown location from the known position. Then, the INS has to know to achieve the goal of the system which is reaching the given position by planning the harmless path by senses the static or moving object and using the map to avoids bumping with them.

The INS can be integrate into specific task such as navigate the public buildings like universities, malls, parking lots, hospitals and museum.2 INS also can be implemented in many devices such as smartphones,2 offline browsers,3embedded device,4 and  in wide areas of autonomous system like self-driving cars, unmanned ground, aerial 5 and underwater vehicles, planetary rovers, robots and even for inspection inside the human body. Besides that, it can be used for emergency situation for fireman, police or ambulance to locate from the complex indoor place so that the operation can be done faster.

Figure 1.??2 Navigation of a car by GPS in closed space

 

Figure 1.??1 Navigation of a car by GPS at open space

 

 

 

 

 

 

 

 

 

 

 

 

 

1.2       PROBLEM STATEMENT

The navigation systems have many applications nowadays. The most used navigation system is GPS, but the transmission of microwaves will be attenuated and scattered when there are roofs or walls which make it inaccurate and distort in indoor environment.  For unmanned vehicle that is more flexible, there should have the navigation system that can dependably detect obstacles in the neighborhood of the vehicle and estimate the pose of vehicle with high accuracy and frequency.

Besides that, INS needs sensors and method before the system can be operated. There are many sensors and methods that have been used for indoor navigation in other references, so this project will recognize and choose the sensors and methods that will be used. After that, there should have the algorithm that can perform calculation, data processing and automated reasoning tasks for the system to detect its position and location. Then, the system will be tested, integrated, and validate into the unmanned vehicle.

The indoor environment is the place that generally covered with roof or walls such as office, factory, and malls. This place usually divided into many sections which is separated by walls and may have many objects or furniture along the way like table, chair, rack, and also human. It also has less light variance compared to outdoor environment because it is usually lighted by indoor lighting sources.  Hence, in order to know whether this system is success or not, it should able to do the work in the given condition.

 The INS should have some criteria that are suitable for the indoor condition. From the described condition above, indoor environment tend to have many obstacles that can be assume that the obstacle is near to each other, so the system should have sensors that able to sense the static or moving object near or far from it and prevent to bump with them. The INS also should have the sensors that can operate with given light condition.

Hence, we know that this system should have some sensors operated in it and there should be a suitable method that is able to combine various sensors that can work together to achieve the criteria mentioned above. Next, it should have algorithm that can plan the desired location according to collected data. Finally, these sensors, method and algorithm will be integrated in one system and develop a model to simulate the system.

 

 1.3      OBJECTIVEs

1.      To select sensor for INS in unmanned vehicle.

2.      To define algorithm to find location of vehicle and map the environment.

3.      To simulate system to unmanned vehicle.

 

1.4       METHODOLOGY

The method used in this project firstly is identifying the sensors and method that are suitable for INS generally and for unmanned vehicle specifically in other previous project by collecting many references. Secondly, discover the algorithm to make calculation, data processing and automated reasoning tasks to find location and position that suit unmanned vehicle. This process can be simulated in MATLAB software that use C language to know if it is successful or not. Next, integrate and validate system to unmanned vehicle. In this project, four degrees of freedom is being used which is more suitable for unmanned ground vehicle rather than unmanned aerial or underwater vehicle that is using six degree of freedom which are more complex.