ultrasonic radar
TRANSCRIPT
ULTRASONIC RADARULTRASONIC RADAR
AIM OF THE PROJECTAIM OF THE PROJECT
NON CONTACT MEASUREMENT OFNON CONTACT MEASUREMENT OF
DISTANCE OF AN OBJECT USINGDISTANCE OF AN OBJECT USING
ULTRASOUNDULTRASOUND
OBJECTIVES OF THE PROJECT
To design a handy device for non-contact measurement of distance.
For measurement of shorter distances only.
Using a microcontroller for better understanding of its functioning.
Less cost manufacture.
ULTRASOUND ???
These are waves of frequency greater than 20KHz.
They travel with velocity of sound.
Because of shorter wave length they travel as sharp beam.
They undergo reflection.
BLOCK DIAGRAM
PIC 16F72MICROCONTROLLER
FND SCREEN
TRANSDUCERDRIVER CIRCUIT
ULTRASONICTRANSMITTER
ULTRASONICRECEIVER
AMPLIFIER
ENVELOPEDETECTORCOMPARATORSIGNAL
HOLDINGCIRCUIT
THRESHOLDVOLTAGE = 0.4V
KEYPAD
INTERNAL STRUCTURE OF ULTRASONIC TRANSDUCER
TRANSMITTER
TRANSMITTERTRANSMITTER
RECEIVER
OPERATIONAL AMPLIFIERSOPERATIONAL AMPLIFIERS
1010
1002
k
kR
RA
i
f
10001001021 AAA
dBAAdB 601000log20log20
ENVELOPE DETECTORENVELOPE DETECTOR
COMPARATORCOMPARATOR
ba
ccbref RR
VRV
MRa 1
kkRb 4751.46
= 0.4V
SS RR QQ QQ`̀
RemarkRemark
00 00 11 11 IllegalIllegal
00 11 11 00 SetSet
11 00 00 11 ResetReset
11 11 QQ QQ`̀Previous Q statePrevious Q state
SIGNAL HOLD CIRCUIT
CCP
1.5ms
RA5 enable output pin goes high
PIC & LED INTERFACE
PROCESS EXPLANATION
FLOW CHARTFLOW CHART
CAPTURE PROCESS
THE LED DISPLAYTHE LED DISPLAY
7 SEGMENT COMMON ANODE
LED INTERFACELED INTERFACE
APPLICATIONSAPPLICATIONS
Robotics & AutomationRobotics & Automation Car backing SystemCar backing System ExplorationExploration
FURTHER DEVELOPMENTFURTHER DEVELOPMENT
Assistance for the blindAssistance for the blind Velocity meterVelocity meter Long range and short range mode Long range and short range mode
selection.selection. PC interface.PC interface. Periphery mapper.Periphery mapper.