Analysis relative behavior of a object in 3D space

Name: Pijus Kumar Sarker Student ID: 103945877

Submit Date: December 12, 2013 This survey is completely done by Pijus Kumar Sarker.

Signature: ____________________

Abstract Main observation of this project is to analyze change of motion and direction of a physical element in a three-dimension space while all of its references will change at a random pattern and the environment will apply multiple forces on the object. From the resultant data we will know the behavior of the object in a unknown environment. This analysis can help us to solve many real-life problems, like the movement of a boat in storm. To reduce the complexity of the experiment we have reduced the problem to very simple problem. A virtual ball will be in a 2D plane and initially moving at a constant speed in a specific direction. Now the change of environment will affect the velocity and direction of the ball. In this analysis environment means, the reference plane, air forces, gravity.

Table of Contents Chapter 1 Introduction Chapter 2 Survey Chapter 3 Investigation Chapter 4 Implementation Chapter 5 Conclusion Bibliography

INTRODUCTION The focusing idea of this survey is to exploring unknown or versatile environment where it is not suitable for living beings to do the survey. In those cases we can use machine-learning approach to get the necessary measurements and real data. Using reduction approach we have reduced the problem to a small problem and represented in virtual world. I have used the basic law physics, like Newtons law on motion, and some vector rules to simulate the work. In the virtual world I have created a versatile environment with some elements as bellow,

1. A ball 2. Movement of reference plane 3. Variation of air force

A ball will be in a virtual plane and initially the ball will be moving at a constant speed to a specific direction. In the original experiment the movement will be controlled at some level. But the environment will affect the movement of the ball. Like a boat is moving at 3Km/hr to east but then the air flows strongly from east to west, which will decrease the speed of the boat and also the direction. In our project we introduced random movement of the plane in 3D space, which is the reference for the ball. Here we have given users to control to move the plane as they wish that will affect the motion of the ball. Also introduced different airflow regions in the path of ball. So the ball will again face unknown forces. Air forces will be controlled by the system and will change its strength randomly in each experiment.

Including the whole idea of reduced problem we can consider it as a small game. The scenario will be like, you have started from your home to a shop in your car and in the way you faced a massive earthquake or heavy storm then you need to reach a nearest safe place to go. As like as the example, the ball will be start moving at a constant speed towards the goal and several air forces will affect the direction and speed of the ball. But you can still control the ball by moving the plane and guide the ball to the goal.

SURVEY Before start concentrating on my work I would like to mention some relevant work. Most of them are remote controlling of a machine or theoretical approach to acquire information form a environment. Below I am describing some of the relevant problems

Localization for Mobile robots: Localization is the estimation of a robot's location for sensor data, is a fundamental problem in mobile robotics. Here localization means position estimation or position control. They maintain a probability density over the space of all locations of a robot in its environment. It is robust to approximate model of the environment and noisy sensors.

Planning and Exploration for Robot-Sensor Systems: Here they considered the view-planning problem where a range sensor is mounted on a robot mechanism with non-trivial geometry and kinematics. The robot-sensor system is required to explore the environment for obstacles and free space. They presented an information theoretical approach in which the sensing action is viewed as reducing ignorance of the planning space, the C-space of the robot. The concept of C-space entropy is introduced as a measure of this ignorance.

Realistic movement display in virtual reality: In the research a

virtual object display apparatus displays an object moved in three-dimensional virtual space. A key frame memory section previously stores move data of each part of the object by unit of action of the object's movement in three-dimensional virtual space. A swing calculation section calculates the change of a basis point of the object by unit of action according to the move

data of each part of the object. A display position set section calculates the change of display position corresponding to the change of the basis point in three-dimensional virtual space by unit of action. A display section displays the object movement in three-dimensional virtual space according to the display position by unit of action.

Moving objects in space: As manipulation in immersive virtual

environments is difficult because users must do without the haptic contact with real objects. So rely on in the real world to orient themselves and their manipulation. To compensate for this lac, they propose exploiting the one real object every user has in virtual environment, his body. The present a unified framework for virtual-environment interaction based proprioception, a person's sense of the position and orientation of his body and limbs.

Automated Tracking and grasping a moving object: Most robotic

grasping tasks assume a stationary or fixed object. So they explore the requirements for tracking and grasping a moving object. The focus of our work is to achieve a high level of interaction between a real-time vision system capable of tracking moving objects in 3-D and a robot arm with gripper that can be used to pick up a moving object. There is an interest in exploring the interplay of hand-eye coordination for dynamic grasping tasks such as grasping of parts on a moving conveyor system, assembly of articulated parts, or for grasping from a mobile robotic system.

All these problems are some extend relevant to my problem but not exactly.

Investigation In my research I am also analyzing the localization of a object in a unknown environment and visualize the scenario using java 3D. I have created a virtual environment with air forces and a base plane. The simple we can say that the change of objects natural movement base on environmental forces (air force, displacement of plane and gravity of ball). Here is the system design of my research.

Goal Checker

Movement

User Interaction

Plane Movement Ball

Movement

Air Force Calculate Velocity

Calculate Direction

Velocity

Goal Checker: The goal checker system will check the current position of the ball and identify whether goal is reached or not. User Interaction: This system will take the user inputs or identify if there is any user interaction on the system. Movement: The movement system will handle all the movements of each element in the environment, like plane movement, ball movement. Plane Movement: Plane movement system will take user interaction as input and display the plane movement or and also calculate the amount of rotation of the plane and keep this rotation. Air Force: Air force system is free of user interaction. The plane is randomly divided in several parts where different air forces will be applied. If the ball is in one of the air force region then the ball will affect by that amount of air force. Ball Movement: Ball movement will be divided in two subsystems, Velocity and Direction. This system will display the balls movement based on the new velocity and direction. Calculate Velocity: This system will calculate velocity of the ball based on the air force, previous velocity and plane movement. Calculate Direction: The direction system calculates the resultant direction caused by air force and movement of plane.

Process and Algorithm Initially the ball will be moving at a constant velocity Vi making angle i with respect to its initial position. Then check if there is any user interaction. If there is any user interaction, here movement of plane, then it will calculate the new velocity Vt and resultant direction t in its previous direction and air force Fai . Now the ball will continue to move according to new velocity Vt and direction t . After each movement at t times it will check whether goal is reached or not. If goal is reached then it will stop and report goal is reached. In each move the system also checked whether the ball is on the plane or out of the plane. Equations: Initial velocity, Vi : Vi = v constant velocity. If there is no user interaction the ball will continue move distance S,

S = vt When air force Fai and gravity force added the we calculate the net force by, Fnet = Fai+Fmg + Fi Here, Fi = initial force Fnet = summation of all forces applied to the ball. Fai = the air force Fmg = force due to gravity Now, Fnet = ma, where m is the mass of the ball, which is constant With vector analysis we can divide the force to its coordinate system. Fnet = Fnx + Fny

Fnx = Fax + Fix + Fmgx Fny = Fay + Fiy + Fmgy And Fnx = Fnet cosr where r is the rotation of the plane Fny = Fnetsinr

New direction, n = tan1 Fny

Fnx

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#$

%

&'

New velocity, Vt = Vi + at, where a = Fnet/m

Fig 1: Effect of multiple forces on an object

Fi

Fair

Fmg Fnet

Flow chart of the Algorithm

Start

Initialize system

User Interaction

Plane Movement

Ball Movement Air Force

Position Detect New Velocity New Direction

Goal Found?

Stop

The view of the environment is as like bellow.

Fig 2: Game structure

IMPLEMENTATION I am representing the scenario with virtual reality because it is one of the best technologies to visualize environment and interact with it, which is one of the major requirement for my project. In such exploration research real-life experiments is very dangerous and costly. Thats why we are using virtual reality doing such experiments. With the help of virtual reality, i am creating a simulation of the problem. The interaction part is most important where the game player will be given control to guide the ball. How I am using virtual reality I am using java3d as a virtual reality tool. There are several features in java3D that helps me to create a virtual world for my experiment and interact with it. I have used GeometryArray to create the plane and goal object. To differentiate different air force regions I have used TextureLoader . To create the ball I have used Sphere class. For visualization of rotation or movement of the plane I used rotY(), rotX(), mul() functions that helps to rotate the plane to a given angle. To know about the current position of the ball I used . get() method that gives me the (x,y,z) value of the object. This is very important for my project to know the current position of the object. Based on the position of the ball in the plane different air force are applied and the velocity and direction is also changed. Track about the experiment time I have used Timer class. For interaction I have used keys. That means with the keys one can move the plane and guide ball towards the goal but other forces will affect the movement. I have used ActionListener, WindowListener, KeyListener class and keyPressed() function. To identify the key events I have used getKeyChar() function.

Here are the keys I am using to move the plane, Key Description A Move the left side of the plane upward and right side

downwards. D Move the right side of the plane upward and left side

downwards S Move the start end upwards and goal end downwards W Move the goal end upwards and start end downwards I Reset the every element to its initial position There are several cases of plane movement and forces on ball as bellow 1. Move AD up and BC down

2. Move BC up and AD down

3. Move AB up and CD down

4. Move CD up and AB down

During the experiment it will save all the forces applied to the ball and the changes in velocity and direction. These information will help us to analyze the unknown environment.

Program Output:

Fig 3: Initial Scenario

Fig 4: Left side moved up

CONCLUSIONS Based on the survey of related work on exploring unknown environment and my research, it is evident that my work will be useful for guiding a object in a space where it will face different forces, like air, gravity. This simulation to guide a object in a unknown environment while practicable experiments are very dangerous and costly. It will be very useful tool to do several measurements in aero dynamics, auto driving and simulation tool for construction of high-rise buildings. We are able to simulate different experiments before real-life experiments, which will give us information about the environment and create a suitable element that will survive in that environment.

BIBLIOGRAPHY 1. Gibbs, J. Willard - Vector Analysis by (1839-1903) 2. Harry F. Davis, Arthur David Snider - Introduction to vector analysis 3. Wolfgang Stuerzlinger, Darius Dadgari Ji & Young Oh - Reality-Based Object Movement techniques for 3D (2006) 4. W. Burke Applied Differential Geometry (1985) 5. Paolo Fiorini, Zvi Shiller Motion planning in dynamic environments using the relative velocity paradigm 6. Naoko Umeki, Miwako Doi, Kabushiki Kaisha Toshiba Virtual object display apparatus and method employing viewpoint updating for realistic movement display in virtual reality. 7. Mark R. Mine, Frederick P. Brooks Jr1 Moving object in spage: Exploiting proprioception in virtual-environment interaction 8. Michael Chen, S. Joy Mountfurd, Abigail Sellen A study in interactive 3-D Rotation using 2-D control Devices. 9. Kurt A. Goszyk Three dimensional object path tracking 10. Jock D. Mackinlay, Stuart K. Card, and George G. Robertson Rapid controlled movement through a virtual 3D workspace 11. Sukhan Lee, Youngchul Kay An accurate estimation of 3-D position and orientation of a moving object for robot stereo vision. 12. Koichi Hirote, Masaki Hirayama, Atsuko Tanaka, Toyohisa kaneko Representation of force in object manipulation.

13. Blaine Bell, Steven Feiner, Tobias Hollerer The force and motion conceptual evaluation and the evaluation of active learning laboratory. 14. James E. Cutting High Performance computing and human vision. 15. Yong Yu, Kamal Gupta - A Measure for View Planning and Exploration for General Robot-Sensor Systems in Unknown Environments

16. Feng Lu, Evangelos Milios - Robot Pose Estimation in Unknown Environments by Matching 2D Range Scans (2006)

17. Susanne Albers and Monika R. Henzinger - Exploring Unknown Environments