Last updated on July 18th, 2023 at 07:34 pm
We hear a lot about autonomous cars; But what’s the actual technology that makes them possible? World-renowned firms like Tesla and Google furnish their cars with laser sensors to enable automobiles to see other vehicles, pedestrians, and other obstacles found on the road while driving. Unluckily, these detection techniques are expensive, but other alternative gadgets are for performing the same role. The question remains whether these other options are efficient enough to replace the more valuable tools for automobile industries’ custom solutions. This article will navigate what radar and Lidar are, how the two systems work, the pros and cons, and their differences.
By definition
What is Lidar
Lidar is also referred to as Light Imaging Detection and Ranging. That is a technology that senses objects found on the surface as well as their sizes and constitution. It’s the latest technology after radar, and it uses laser light pulses to examine the environment as opposed to sound waves. Additionally, it was invented by NASA and the US military to measure distance in space.
Currently, the lidar system fashion is relatively compact and enhances companies to apply this technology for new roles. A device that uses lidar systems is also referred to as a scanner that can generate a digital copy of any physical object and save time compared to beginning from scratch.
How Lidar remote sensing operates
The device releases laser pulses that go outwards in various directions until the waves reach where the object is and then bounces and return to the receiver. Sonar uses the same principle, only that it uses sound waves. With the use of lidar technology, the light is a million times faster than the sound. For instance, during a hurricane with lightning, we first hear the sound, and then after a few seconds, the sound is heard.
Such speed enables the gadget to receive information from an immense number of surges every second. That implies that the info is updated more frequently, and due to that, precise data is received. Besides, an inner processor saves every bounce point of a laser and provides a 3D image of the environment. These lidar techniques are usually applied on an installed onboard plane to allow the creation of precise maps.
Moreover, the same processor can calculate the distance between a detected object and a lidar receiver using a simple formula where laser speed and reflection are well known. This technique found its application in independent companies, and it has taken root there. All self-driving cars use Lidar to scrutinize their surroundings.
Functions
- Laser waves reach the obstacle.
- It emits laser signals.
- It enhances the registration of a laser pulse.
- The technology enables the reflection of signals from the receiver.
- Also, it enhances laser waves to reach an object.
Where is Lidar used?
The innovation of this technology has made enormous impacts on the development of self-driving car industries.
In the US and specifically at Portland State University, the lidar system is used to check tree growth progressions sprawling ecosystems with larger surface areas.
The help of Lidar NASA (National Aeronautics Space Administration) has calculated the stratospheric temperatures by determining the density of atmosphere elements.
What is the vulnerability of Lidar?
When using lidar technologies, it easy to create unrealistic echoes that make the device detect objects further than they’re using transmitters with a similar wavelength that Lidar has. Furthermore, only one transceiver and two pulse generators can provide several copies of lidar signals and send them to the receiver, making the device see non-existing things.
Advantages of lidar systems
- The system readily detects images located in the range of about 30-200m
Disadvantages
- The system is a letdown when it comes to identifying objects in the area.
- It provides low optical recognition.
- Lidar only works in light conditions.
What is radar?
Radar is also referred to as Radio Detection and Ranging. It is used in sensing objects at a distance, show their speed and disposition. Besides, radar is a standard device because police use it in most areas to detect and regulate vehicles that are driven above the speed limit.
How does it work?
For instance, the sound echo makes us define how far away something is by using sound signal reflection from solids. The time is taken for a sound to travel both backs and forward is fixed on the distance between the source of the sound and the surface that bounces the waves.
This principle is based on radar systems, with the only difference that radar uses radio gestures rather than sound. Radio waves usually travel much further distance than sound signals and are generally undetectable to human sensory organs. Moreover, radio and light waves have the same speed. Hence, based on how fast data gets updated in each system, both radar and Lidar have a fair draw.
How is radar used?
In most cases, radar is used for military functions. Planes equipped with radar technology can accurately determine the altitude and sense other air devices in the area. Besides, marine radar is used in the same way to measure the distance between crafts to prevent any collisions. Nevertheless, technology is used for a short-term prediction for monitoring wind and precipitation. The geologist occasionally uses radar to determine the composition of the earth’s crust.
Advantages of radar technology
- Its less expensive
- The system performs well in fogs, rain, and snow weather conditions.
Disadvantages of radar technology
- It’s angularly less accurate.
What is the Difference between LiDAR and RADAR?
| ASPECT | LIDAR | RADAR |
|---|---|---|
| Principle | Lidar systems emit laser pulses and measure the time it takes for the reflected light to return to the sensor. | Radar systems emit radio waves and detect the reflected signals. |
| Electromagnetic Spectrum | Lidar systems use laser beams in the optical spectrum (typically near-infrared or sometimes ultraviolet). | Radar systems use radio waves in the radio frequency spectrum. |
| Resolution and Accuracy | Lidar provides high-resolution data with precise ranging accuracy. | Radar generally has lower resolution and its accuracy depends on factors like frequency and system design. |
| Environmental Sensitivity | Lidar can be affected by environmental factors like dust, smoke, or heavy rain. | Radar is less affected by environmental factors and can penetrate certain obstacles like rain. |
My final thought
The sensor technology’s primary role is to ensure the passengers’ safety in the self-driving vehicles by keeping a safe distance from obstacles on the road. Whether you choose Lidar or radar, both two technologies function equitably. Still, both come with a set of strengths and weaknesses. A car with Lidar sees the entire world accurately; radar systems are small and less expensive. Honestly, it is still too early to pick the winner between the two as both technologies go through a turbulent period of evolution. Which between the two will dominate the self-driving cars industries? Only time will reveal this.
