to triangulate position of the robots used in GE423. Each of three
transmitters uses a distinct frequencies: 23 kHz, 31 kHz, and 40 kHz.
The 2812 DSP is used to measure signal timing and calculate
position based on these values. The design of the electronics, as
well as discussion of the software development is presented below.
1.2 Transmit Circuit
A schematic of the transmit circuit looks like
Ultrasonic Transmiter
The photo depicts the schematics for an Ultrasonic Transmitter
which will send a signal out into it's surrounding area.
The Ultrasonic receiver will detect this signal once it bounces
off from an object. The combination of these two sensors will
allow the aerial robot to detect objects in its path and maneuver
around the objects. These sensors will be attached in front of
the plane. These sensors will also help the robot navigate
through the halls of any building.. This tutorial will show how to
construct and test one pair of ultrasonic proximity receiver and
transmitter.
which will send a signal out into it's surrounding area.
The Ultrasonic receiver will detect this signal once it bounces
off from an object. The combination of these two sensors will
allow the aerial robot to detect objects in its path and maneuver
around the objects. These sensors will be attached in front of
the plane. These sensors will also help the robot navigate
through the halls of any building.. This tutorial will show how to
construct and test one pair of ultrasonic proximity receiver and
transmitter.
more
Ultrasonic Receiver
Ultrasonic Receiver
The photo depicts the schematics for an Ultrasonic Receiver whichwill detect the signal from the Ultrasonic Transmitter once it
bounces off from an object. The combination of these two sensors
will allow the aerial robot to detect objects in its path and maneuver
around the objects. These sensors will be attached in front of the
plane. These sensors will also help the robot navigate through the
halls of any building.. This tutorial will show how to construct and
test one pair of ultrasonic proximity receiver and transmitter.
more
Sonar sensors
Sonar sensors
This is a simple system. The transmitter emits an ultrasonic signal
(40kHz). The 555 timer chip of the transmitter provides the driving
40kHz signal. Every time the reset pin (pin4) of the 555 timer goes
high, a resulting signal of 40kHz on pin 3 is used to drive the
ultrasonic transducer. Then, the receiver simply listens for the return
echo after it bounces off an object. The small echo signal, when
detected, is amplified 1000 times using a standard operational
amplifier (LM741 op-amp). The signal is then fed into a tone
decoder (LM567) set to lock onto a 40kHz signal. The output of the
tone decoder is HIGH when no echo is heard and swings LOW
when an echo is detected. The output from the tone decoder can
now be fed into a microcontroller or some other type of IC to
determine when an echo was received. To help minimize false
triggering, the output is fed into a voltage comparator set to trigger
at the appropriate level. The LED at the output of the comparator
acts as a visual indicator when an echo is detected (very useful
when debugging). The typical range of this system is from a few
inches to 5-6 feet, depending on the quality of the components,
shielding, and most important, tuning.more
(40kHz). The 555 timer chip of the transmitter provides the driving
40kHz signal. Every time the reset pin (pin4) of the 555 timer goes
high, a resulting signal of 40kHz on pin 3 is used to drive the
ultrasonic transducer. Then, the receiver simply listens for the return
echo after it bounces off an object. The small echo signal, when
detected, is amplified 1000 times using a standard operational
amplifier (LM741 op-amp). The signal is then fed into a tone
decoder (LM567) set to lock onto a 40kHz signal. The output of the
tone decoder is HIGH when no echo is heard and swings LOW
when an echo is detected. The output from the tone decoder can
now be fed into a microcontroller or some other type of IC to
determine when an echo was received. To help minimize false
triggering, the output is fed into a voltage comparator set to trigger
at the appropriate level. The LED at the output of the comparator
acts as a visual indicator when an echo is detected (very useful
when debugging). The typical range of this system is from a few
inches to 5-6 feet, depending on the quality of the components,
shielding, and most important, tuning.more
Ultrasonic Sensor and Ultrasonic Book
