Development And Calibration Of A Center Of Pressure Apparatus
The development and calibration of a center of pressure measurement apparatus represent a pivotal step in biomechanical research, particularly in fields such as sports science and rehabilitation engineering. This innovative device, designed with precision engineering, enables the accurate determination of the point where the total pressure vector on a surface is assumed to act, crucial for understanding human balance and movement dynamics. Through meticulous calibration procedures, including sensor alignment and validation against standardized loads, this apparatus ensures reliability and accuracy in center of pressure measurements. Its multifunctional design and robust calibration process make it an indispensable tool for researchers and practitioners seeking to explore human movement patterns and develop targeted interventions for various applications, from athletic performance enhancement to clinical rehabilitation strategies.
The Centre of Pressure Apparatus has been designed to determine the static thrust exerted by a fluid on a submerged surface and allow comparison of the measured magnitude and position of this force with simple theory. A fabricated quadrant is mounted on a balance arm, which pivots on knife-edges. The knife-edges coincide with the centre of arc of the quadrant. Thus, of the hydrostatic forces acting on the quadrant when immersed, only the force on the rectangular end face gives rise to a moment about the knife-edges. The balance arm incorporates a balance pan for the weights supplied and an adjustable counterbalance. This assembly is mounted on top of an acrylic tank, which may be leveled by adjusting screwed feet. An indicator attached to the side of the tank shows when the balance arm is horizontal. Water is admitted to the top of the tank by a flexible tube and may be drained through a cock in the side of the tank. The water level is indicated on a scale on the side of the quadrant.
Title page
Certification
Dedication
Acknowledgement
Abstract
Table of content
CHAPTER ONE
1.0 Introduction
1.1 Background of the study
1.2 Aim of the project
1.3 Objectives of the study
1.4 Scope of the study
1.5 Purpose of the project
1.6 Significance of the study
CHAPTER TWO
Literature review
2.1 Overview of hydrostatic pressure
2.2 Historical background of hydrostatic pressure
2.3 Hydrostatic example (dam)
2.4 Historical usage for sailboats
2.5 Review of movement of center of pressure for aerodynamic fields
CHAPTER THREE
Methodology
3.1 System description
3.2 Equipments and apparatus
3.3 Objectives of the experiment
3.4 Method
3.5 Technical data procedure
CHAPTER FOUR
4.1 Result
4.2 Calculation
CHAPTER FIVE
Conclusion
1.0 INTRODUCTION
1.1 BACKGROUND OF THE STUDY
The center of pressureis the point where the total sum of a pressure field acts on a body, causing a force to act through that point. The total force vector acting at the center of pressure is the value of the integrated vectorial pressure field. The resultant force and center of pressure location produce equivalent force and moment on the body as the original pressure field. Pressure fields occur in both static and dynamic fluid mechanics. Specification of the center of pressure, the reference point from which the center of pressure is referenced, and the associated force vector allows the moment generated about any point to be computed by a translation from the reference point to the desired new point. It is common for the center of pressure to be located on the body, but in fluid flows it is possible for the pressure field to exert a moment on the body of such magnitude that the center of pressure is located outside the body.
1.2 AIM OF THE PROJECT
The main aim of this work is to setup an apparatus that is used in determining the centre of pressure and the thrust on a body immersed in a fluid basically water.
1.3 OBJECTIVE OF THE PROJECT
To determine the hydrostatic thrust acting on a plane surface immersed in water.
To determine the position of the line of action of the thrust and to compare the position determined by experiment with the theoretical position.
1.4 SCOPE OF THE STUDY
From this experiment we are able to measure the moment due to the total fluid thrust on a wholly, or partially, submerged plane surface to be directly measured and compared with theoretical analysis. The plane area may be tilted relative to the vertical so that the general case may be studied. The water is contained in a clear Perspex quadrant, the cylindrical sides of which have their central axes coincident with the axis about which the turning moments are measured. The total fluid pressures on the secured surfaces therefore exert no moment about this pivot, the only moment being due to the fluid pressure on the plane test surface. This moment is simply measured by weights suspended from a level arm.
1.5 PURPOSE OF THE PROJECT
The purpose of this work is:
Determination of force due to hydrostatic pressure
Determination of Center of pressure
1.6 SIGNIFICANCE OF THE STUDY
Very efficient
Rigid construction
Easy to operate
Long lasting
CHAPTER FIVE
5.1 CONCLUSIONS
At the end of this work, the theoretical and practical aspect of this work was carried out, all the result was calculated using both theoretically and experimentally. This study allows students to measure the moment due to the fluid (hydrostatic) thrust on a fully or partially submerged plane. The plane works in either a vertical or inclined (angled) position. Students then compare their measurements with theoretical analysis.
The equipment consists of a vertical panel that holds a clear plastic quadrant, to which students add water. The quadrant has engraved lines to help students keep the plane in a vertical or angled position.
The cylindrical sides of the quadrant have their central axis coincidental with the moment measurement axis. The total fluid pressures on these curved surfaces therefore exert no moment about this pivot. Therefore, the moment is only due to the fluid pressure on the plane test surface. Students measure this moment using weights suspended from a level arm. A scale on the panel of the apparatus shows the head of water.
SHARE PROJECT MATERIALS ON:
A Center of Pressure (CoP) apparatus is a device used to measure and analyze the distribution of forces exerted by a fluid (usually air or water) on a surface. This apparatus is commonly used in fields such as aerodynamics, hydrodynamics, and biomechanics to understand how forces interact with objects in a fluid medium.
The development and calibration of a Center of Pressure apparatus involve the following steps:
- Design and Construction: The apparatus is designed and constructed to facilitate the measurement of forces exerted by the fluid on the surface of interest. It typically consists of a test object or surface, sensors (such as pressure transducers), data acquisition equipment, and a means to control the fluid flow.
- Sensor Placement: Pressure sensors are strategically placed on the surface of the object to measure the local pressure distribution. These sensors are positioned in a manner that allows for the accurate determination of the center of pressure. The center of pressure is the point where the net force acts on the object, and it can vary with changes in fluid conditions and object orientation.
- Calibration: Calibration is the process of determining the relationship between the output of the pressure sensors and the actual pressure values. This is crucial to ensure accurate measurements. Calibration is typically performed using known pressures and comparing them to the sensor readings. Calibration data is used to create a calibration curve or equation that relates sensor outputs to actual pressures.
- Data Acquisition System: A data acquisition system is set up to collect pressure data from the sensors. This system converts analog sensor signals into digital data that can be processed and analyzed.
- Fluid Flow Control: Depending on the application, the fluid flow around the object may need to be controlled. This could involve adjusting the flow rate, angle of attack (in aerodynamics), or other relevant parameters.
- Measurement and Analysis: Once the apparatus is set up and calibrated, experiments are conducted. The pressure distribution data collected by the sensors is used to calculate the center of pressure at different conditions. This information helps researchers understand how forces act on the object and how they might affect stability, control, and other relevant factors.
- Validation and Iteration: The accuracy and reliability of the apparatus are validated by comparing the calculated center of pressure with theoretical or known values. If discrepancies are observed, adjustments might be made to the setup or calibration process, and the validation process is repeated until satisfactory results are obtained.
- Reporting and Documentation: The results of the experiments, calibration procedures, and any modifications to the apparatus are documented for future reference and to share findings with the scientific community.
In summary, the development and calibration of a Center of Pressure apparatus involve designing, constructing, calibrating, and using the apparatus to measure how fluid forces interact with a surface. This process is essential for various scientific and engineering applications where understanding the distribution of forces on objects in fluid environments is crucial.