Fundamentals of Measurement Technology Prof Wang Boxiong
Fundamentals of Measurement Technology (1) Prof. Wang Boxiong
1 Introduction 1.1 Measurement technology: background and development 1.2 Essence of measurement and its basic prerequIsItes 1.3 Standards and their units
1.Introduction 1.1 Measurement technology: background and development 1.2 Essence of measurement and its basic prerequisites 1.3 Standards and their units
1Introduction Major points to study 1. What is measurement technology all about? 2. Significance of measurement technology in science, production and social progress 3. Major components of a measuring system and their respective functions 4 What to study
Major points to study 1. What is measurement technology all about? 2. Significance of measurement technology in science, production and social progress 3. Major components of a measuring system and their respective functions 4. What to study 1.Introduction
1.1 Measurement technology: background and development Historical background kNowledge acquisition often begins with measurement MEasurement science(metrology )was generated and developed with the development of human society dEarly measurements >Length(distance), time, area and weight, etc
❖ Historical background ❑Knowledge acquisition often begins with measurement. ❑Measurement science (metrology) was generated and developed with the development of human society. ❑Early measurements: ➢Length (distance), time, area and weight, etc. 1.1 Measurement technology: background and development
1. 1 Measurement technology: background and development UThe field of measurement was enlarged continuously, and the means and methods for measurements became more sophisticated >Elle, created by the egyptians in about 3000 B C a unified standard of length Defined as the length of the forearm of the pharao measured from his elbow to the tip of his stretched middle finger plus the width of a palm twig in his hand Realized with a black granite as the primary standard Emperor Qin Shi established a unified system of weights and measures and gave severe punishments to those who violated the system
❑The field of measurement was enlarged continuously, and the means and methods for measurements became more sophisticated: ➢Elle, created by the Egyptians in about 3000 B.C. ▪ A unified standard of length. ▪ Defined as the length of the forearm of the Pharao measured from his elbow to the tip of his stretched middle finger plus the width of a palm twig in his hand. ▪ Realized with a black granite as the primary standard. ➢Emperor Qin Shi established a unified system of weights and measures and gave severe punishments to those who violated the system. 1.1 Measurement technology: background and development
1. 1 Measurement technology: background and development u Measurement technology plays an important role in promoting production development and social progress O The rapid development of science and technology has invigorated measurement technology, and the development of modern electronics, especially the information technology has pushed forward further its development O Every subject can find its trace in measurement technology. O The development of measurement technology has in turn promoted the development of other subⅰects
❑Measurement technology plays an important role in promoting production development and social progress. ❑The rapid development of science and technology has invigorated measurement technology, and the development of modern electronics, especially the information technology has pushed forward further its development. ❑Every subject can find its trace in measurement technology. ❑The development of measurement technology has, in turn, promoted the development of other subjects. 1.1 Measurement technology: background and development
1. 1 Measurement technology: background and development o The extensiveness. essence and scientific significance of measurement technology > Whatever exists, exists in some amount >I often say that when you can measure what you are speaking about and express it in numbers, you know something about it, and when you cannot measure it, when you cannot express it in numbers your knowledge is of meager and unsatisfactory kind. It may be the beginning of knowledge, but you have scarcely, in your thought, advanced to the stage, Whatever the mater elvin William Thompson)
❑ The extensiveness, essence and scientific significance of measurement technology: ➢“Whatever exists, exists in some amount.” ➢“I often say that when you can measure what you are speaking about and express it in numbers, you know something about it, and when you cannot measure it, when you cannot express it in numbers, your knowledge is of meager and unsatisfactory kind. It may be the beginning of knowledge, but you have scarcely, in your thought, advanced to the stage, whatever the matter be.” 1.1 Measurement technology: background and development -- Lord Kelvin (William Thompson)
1. 1 Measurement technology: background and development cLassification of physical quantities(in terms of time-dependent properties) Static quantities and dynamic quantities aStatic quantity: does not vary or varies slowly with time ODynamic quantity: varies rapidly with time aStatic measurement: the measurement of a static quantity ODynamic measurement: the measurement of a dynamic quantity
❑Classification of physical quantities (in terms of time-dependent properties): ➢Static quantities and dynamic quantities ❑Static quantity: does not vary or varies slowly with time. ❑Dynamic quantity: varies rapidly with time. ❑Static measurement:the measurement of a static quantity. ❑Dynamic measurement:the measurement of a dynamic quantity. 1.1 Measurement technology: background and development
1. 1 Measurement technology: background and development APplications of dynamic measurement >Machine part, vibration measurement >Flight of an aircraft, using dials and instruments to indicate its course, speed. acceleration and mileage etc The process of steel rolling, detecting thickness and width of the rolled strip steel
❑Applications of dynamic measurement: ➢Machine part, vibration measurement; ➢Flight of an aircraft, using dials and instruments to indicate its course, speed, acceleration and mileage etc. ➢The process of steel rolling, detecting thickness and width of the rolled strip steel. 1.1 Measurement technology: background and development
1. 1 Measurement technology: background and development WHether a measurement is static or dynamic is totally relative, sometimes they can be changed with each other OThe kind of the measurement to be performed depends on >what is measured >what are the requirements on the measurement accuracy, stability, etc
❑Whether a measurement is static or dynamic is totally relative, sometimes they can be changed with each other. ❑The kind of the measurement to be performed depends on: ➢what is measured; ➢what are the requirements on the measurement: ▪ accuracy, stability, etc. 1.1 Measurement technology: background and development
