Hey friends, welcome to the YouTube channel
ALL ABOUT ELECTRONICS. So, in this video will get an overview of
the technology which is known as LIDAR. so this LIDAR is the acronym of the term light
detection and ranging. So, now as its name suggests, this technology
uses the light waves or the light source to measure the distance between the object or
in another way we can say that it is used in the range finding applications. So now this is not a new technology and in
fact, it is being used since last more than 50 years. And in the 1960s, it was first used to measure
the distance between the moon and the earth using the lasers. And nowadays it is being used in so many applications
and maybe in the future, you will see that your self-driving car will be equipped with
this LIDAR system. Now, if you see term LIDAR, it sounds very
familiar with the term that is known as the radar and many of you might be already knowing
about this radar system. So now in terms of the working principle,
this LIDAR and RADAR both are quite similar. So, let us find out in this video, what is
LIDAR, how it works and what are the different applications of this LIDAR system, and how
it is different from the radar system. So, first of all, let us understand how this
LIDAR system works. So, now if you see any LIDAR system, the laser
and the detector are the two of the main components which you see inside this LIDAR system. And most of the LIDAR systems works on the
principle of time of light. So, in this principle, the laser in the pulse
form is targeted on the object and the reflection or the scattering from the object it is being
measured by the detector. And at the detective side, the timing between
the transmitted pulse and the received pulses is measured. So let us say, the distance between the LIDAR
system and the object is capital D. So, now if you know the timing difference between
the arrival and the transmitted pulse then using the simple mathematics we can calculate
the distance between the LIDAR system and the object. And here the velocity of this transmitted
light pulse will be at the rate of speed of light. So, this is the basic principle, how every
LIDAR system works. So, now if you see the working principle of
the Radar system, even radar system works on the same principle, that is a time
of flight principle. So now let’s exactly understand what is
the difference between this LIDAR system and the radar system. So, if you see the term RADAR, it stands for
the radio detection and ranging. So, instead of light waves, in case of the
radar system, the radio waves are used for the measurement. So, now if you see the electromagnetic spectrum
then you will notice that the radio waves which are used in radar system are millimeter
waves, while the light waves which are used in the LIDAR system are almost 3 order less
in dimension then the radio waves. So, these radio waves cannot detect objects
which are very small in the dimension. While using the light waves, we can even detective
very small objects. So using the LIDAR system, we can achieve
the much more Precision. So, because of its precision, these LIDAR
systems are used for the 3D mapping of the object or even for the surface scanning of
the object. And using this LIDAR system, we can even scan
the buildings as well as the different terrains. While radar systems are used in applications
where the exit size and shape of the object is not important but the detection distance
is more important. So, basically they are used in military applications
or in air traffic control, where the detection of the object is more important rather than
the size and shape of the object, or even they are used in some range finding applications. Now the advantage of Radar over LIDAR is that
it works even in the harsh environment. So it even works in case of the rain, fog
or even snow. While the LIDAR system cannot work in such
harsh environment. So, now whenever we're discussing the different
technologies which are used for the range finding, so let’s also mention the one more
technology which is used for the range finding, which is known as the Sonar. So in this Sonar technology, instead of the
radio waves or the light waves, the acoustic waves are used for the range finding or measuring
the distance. And mainly this technology is used for the
underwater applications. Alright,so here is the quick comparison between
the LIDAR and the radar system.so as I said earlier apart from the range finding applications,
this LIDAR is also used for the 3D mapping of the object or even for the surface scanning. So, there has to have some mechanism by which
we can rotate this light source so that we can scan the object. So, let us understand, using the LIDAR system
how the object can be scanned. So, let us stay, here we have an object and
we want to measure the depth profile of this object. So in this way, using this LIDAR system, we
can get the depth profile of that object. Now here, the resolution of this depth profile depends
upon the scanning angle of this LIDAR system as well as on the number of samples, which
is being taken by this LIDAR system. So, lesser will be the scanning angle, the more accurate
will be the the depth profile of that object. So, that is being said now let us see the
different components of LIDAR system. Now some of the components we have already
mentioned earlier. So the first component is a laser. Now, the most of the lasers which are used
for this LIDAR system are in the range of near infrared but in some applications like
in underwater applications even green lasers are also used. Now, the second component of this LIDAR system
is the detector, which consists of the photodiode circuit to measure the reflected or the scattered
light which is coming from the object. Then the third component of this LIDAR system
is the optics and the rotating mechanism to scan the object. Apart from that we used to have the timing
electronics to measure the difference between the transmitted pulse and received pulse. So, as I said earlier, this LIDAR system used
to generate the enormous amount of data points in real time, so to compute that data, we
also requires the computer. Apart from these components the GPS and the
IMU, which stands for the inertial measurement unit are also part of this LIDAR system. So, this GPS and IMU are particularly useful
when we have Air Borne LIDARs, that means the LIDAR system is being fitted either in
the helicopter or Airplane or maybe even drone and sometimes maybe even in the satellites. And this Airborne LIDARs are particularly
useful to scan the particular terrain. So, that is being said, now let us see the
different applications of this LIDAR system. So, as I said earlier, apart from the range
finding applications this LIDAR can be used for the 3D mapping as well as surface scanning. So, this LIDAR system can be used for the
3D mapping of any building. So in this way by scanning the building, we
can get the profile of that building in digital form. Apart from that, this LIDAR system can be
used for the police trafficking for the measurement of the vehicle speed. Now so far the radar guns were used for the
measurement of the vehicle speed but because of its higher accuracy nowadays the radar
guns have been replaced by this LIDAR guns. So, apart from the range finding application,
this LIDAR system can be used for the agriculture Research and using this we can help the farmers
to find the area which can give them maximum yield. So, apart from measuring the profile of terrain,
it is also used in the automobile industry. So, as I said earlier you might see the LIDAR
system in your upcoming self driving Cars, where it can be used to scan the object in
front of it in real time and using that it can make the decision accordingly. So, apart from the automobile industries,
this LIDAR system is also used in designing the video games. For example the company EA Sports is using
this LIDAR point clouds to create the most realistic three-dimensional environment of
golf, basketball as well as the football stadiums. And here is the example of a LIDAR point cloud
of a very famous Madison Square Garden. So, in this way, this LIDAR system can be
used in almost all the fields, and if we count the applications then list will go on. So, I hope in this video, you got an overview
of this LIDAR Technology. So, if you have any questions or suggestion
please let me know in the comments section below. If you like this video hit the like button
and subscribe to the channel for more such videos.
