Mechanical

sensors

BASIC ELECTRONICS

TABLE OF CONTENTS: sensors TYPES OF SENSORS MECHANICAL SENSORS TYPES OF MECHANICAL

SENSORS DISPLACEMENT SENSORS VELOCITY SENSORS TORQUE SENSORS FLOW SENSORS

A sensor is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument.Example a mercury in glass thermometer.

Sensors:

Three terms:Transducer A device that converts a primary form of energy into corresponding signal with a different energy forms.

Sensor A device that detect or measures a signal.

Actuator A device that generates a signal.

realworld

actuator

sensor intelligentfeedbacksystem

TYPES OF SENSORSTHERE ARE VARIOUS KINDS OF SENSORS HAVING WIDE RANGE OF APPLICATIONS.SOME OF THEM ARE: MECHANICAL SENSORSNAVIGATIONAL SENSORSOPTICAL SENSORSBIOLOGICAL SENSORSENVIRONMENTAL SENSORS...etc.,

MECHANICAL SENSORS:

TYPES OF MECHANICAL SENSORS:i. DISPLACEMENT SENSORSii. VELOCITY SENSORSiii. TORQUE SENSORSiv. FLOW SENSORS

CLASS OF SENSORS TO MEASURE MECHANICAL PHENOMENON

A flow sensor is a device for sensing the rate of flow of material.

Material may be solid, liquid or gas.Flow rate is measured by weighting

the amount of material on a platform of length L

Flow Sensor

flow (kg/min or lb/min)

weight of material on section of length L (kg or lb)

conveyor speed (m/min, or ft/min)

length of weighting platform

Q

W

R

L

WRQ

L

Flow sensors are based on sensors which measure the transfer of heat caused by the moving medium. This principle is common for micro sensors to measure flow.

Velocimetry: Velocimetry is the measurement of the velocity of fluids.

For measuring velocity and length on moving surfaces, laser surface velocimeters

are used.

Application of flow sensor

velocimeter

Displacement sensors measure the distance an object moves and they can also be used to measure object height and width, position ,displacements, both rotary and linear.

The following are some of commonly used displacement sensors:a) LVDT: A linear variable differential transformer is a transformer

whose core moves along with the distance being measured and outputs a variable analog voltage as a result of this dislacement.

b) Encoders: An encoder is a simple device that can output a digital signal for each small portion of a movement.

c) Potentiometers :A potentiometer converts position information into a variable voltage through a resistor.

Displacement sensors:

a. Thickness measurement.b. Flatness measurement.c. Confirms the shapes of modelled partsd. Measures the curvatures of tranparent

subtratcts.e. Level measurement by 1)float & linkage 2)concentric

cylindrical capacitor.

APPLICATIONS OF DISPLACEMENT SENSORS:

Level measurement by cylindrical capacitor

LVDT

POTENTIOMETER

Torque is a measure of the forces that causes an object to rotate.

Reaction torque sensors measure static torque with a stationary or non-rotating transducer.

Rotary torque sensors use rotary transducers to measure torque.

Torque sensor

Torque meter is a device for measuring and recording the torque on a rotating system, such as an engine, crankshaft, gearbox etc.,

In process testing, monitoring and diagnostics applications.

In measurement of power transmitted through a rotating device.

In controlling complex non-linear mechanical systems.

Used for Power tool measurement.

Application of torque sensor

Velocity sensorVelocity sensors are machines used to detect the

speed of an object, usually a transport vehicle

A wheel speed sensor or vehicle speed sensor (VSS) is a sender device used for

reading the speed of a vehicle's wheel rotation. It usually consists of a

toothed ring and pickup.

The airspeed indicator or airspeed gauge is

an instrument used in an aircraft to display the craft's airspeed, typically in knots, to thepilot. In its simplest form, It measures the difference in pressure between that which is generally around the craft and the increased pressure caused by propulsion. The needle tracks pressure differential but the dial is marked off as airspeed.

Pitometer logs (also known as pit logs) are devices used to measure a ship's speed relative to the water. They are used on both surface ships and submarines. Data from the pitometer log is usually fed directly into the ship's navigation system.

A speedometer or a speed meter is a gauge that measures and displays the instantaneous speed of a vehicle. 

Speedometers for other vehicles have specific names and use other means of sensing speed. For a boat, this is a pit log. For an aircraft, this is an airspeed i ndicator.

M.ARUN(roll 41)

G.PAVAN KUMAR(roll 47)

SRINIVAS .G.(roll 15)

SAI KIRAN G.(roll 33)

THANK YOU

ABHISHEK M.(roll 39)