How sensors and actuators are being used to create self-driven vehicles

Autonomous vehicles aren’t science fiction any more. Top automobile firms and technology giants are working towards making self-driven cars commercially available by 2021.

In the same way how IoT is revolutionizing the industrial organization, self-driven vehicles are revolutionizing the transportation industry, allowing people to travel safely and comfortably.

These connected vehicles have the ability to mitigate pollution owing to their real-time traffic information and smart routing. 

Autonomous motor cars and trucks use Artificial Intelligence and work using sensors, actuators, and complex algorithms, to sense, process, and choose specific actions based on the information gathered.

Depending on the degree of driver intervention, the sensors and actuators are integrated with automotive controls to help optimize the vehicles’ performance.

 

Sensors (cameras, radars, and ultrasonic sensors) perform the critical function of sensing the dynamic conditions on the road.

Processors handle data received from the vehicles’ sensors and direct the actuators to physically perform actions such as changing gears, applying brakes, and steering.

The numerous subsystems, sensors, and actuators that work together can be classified based on the functions they perform.

Here are three aspects of autonomous vehicles where sensors and actuators are used to improve the users’ travel experience.

Navigation and guidance

The navigation and guidance define the mission of self-driven vehicles by determining the users’ location, choosing the best routes, and avoiding delays when on the road.

For instance, if the optimum route to a destination has unforeseen obstacles such as slow traffic or road maintenance, the path will be recomputed in real time, enabling the traveler to reach his/her destination on time.

The primary subsystem used in navigation and guidance is the Global Positioning System (GPS) receiver that uses cameras, radars, and lasers to detect the ever-changing conditions that surround the vehicle.

The camera captures visual data while the radars allow the vehicle to sense the road conditions in visually impaired circumstances such as heavy rains, snowfall, and / or fog.

The spinning lights above the vehicle are the lasers that continuously scan the surroundings, offering a three-dimensional view for better navigation.

These sensors pass the data into complex algorithms (using processors), enabling autonomous vehicles to take the necessary actions.

For instance, if a traffic signal is seen, the sensors, the processors, and the linear actuators will work together using an in-vehicle electronic network (Controller Area Network or CAN bus) to apply brakes and switch off the engine until the lights go green.

Though the GPS subsystem is crucial to the functioning of the autonomous vehicles, the signal is often blocked when they are moving through tunnels, mountains, and canyons or by radio-interference.

Consequently, autonomous vehicles use the inertial measurement unit (IMU) which comprises of sensors, namely MEMS-based gyroscopes and accelerometers to calculate the motion and position of the cars regardless of the signal obstruction.

The IMU is a centralized system that monitors the location of other sensor systems in relation to the vehicles’ position.

Apart from offering guidance to the vehicles, IMU is critical to the safety of the vehicle users. You will read more in this regard in the subsequent point.

Automated vehicles are also connected to the Cloud which constantly offers updated data, based on the collective intelligence of all the vehicles on the road.

For instance, it informs the system about a defective traffic signal or a traffic jam, enabling the vehicle to adjust to the hurdles and take necessary actions.

Driving safety

Self-driven vehicles have a 360◦ view of the surroundings and can locate other vehicles, obstacles, and bystanders on the road, reducing the incidence of accidents.

Advanced features such as light assist, lane assist, adaptive cruise control, and emergency assist ensure the safety of the vehicle owners and others on the road.

An array of cameras and detectors capture multiple images and the processors help make sense of the heavy graphics based on the visibility on the road.

The LiDaR (short for Light Detection and Ranging) is used for primary vision, providing accurate 3D graphics of the surrounding environment using the scanning mirror present on the top of these vehicles.

The data is used by the processors to identify objects, predict a crash, and/or determine the vehicles’ motion vector. In advanced car models, a large number of detectors and timed cameras are used to increase the resolution of the 3D data, reducing the risk of collisions.

The radars present on the front and rear bumpers of self-driven vehicles are useful in automated parking lots and bumper-to-bumper traffic.

The IMU is critical in calculating sudden changes in the vehicles’ trajectory speed, enabling the system to predict the risk factors that could lead to mishaps.

For instance, the slightest change in the slip angle can cause vehicles to skid, spin or roll. IMU helps anticipate such safety-related issues, enabling the system to take the necessary preventive measures.

In short, automated vehicles use a combination of sensors to reach their autonomous capability and make transportation safe and comfortable for the users.

Car performance management

Apart from the navigation and the safety of the users, firms involved in designing and manufacturing automated vehicles are spending a considerable amount of time and energy to make self-driven vehicles power-and-fuel-efficient.

Numerous sensors, actuators, application-specific circuit boards, and subsystems are installed in self-driven vehicles to manage system-level operations, power consumption, fuel efficiency, and thermal dissipation.

Regular monitoring of the voltage in the vehicle battery is crucial for the safety of the users and the functionality of the vehicle. Autonomous vehicles use milliohm meters or shunts along with differential amplifiers to effectively measure the voltage drop in the batteries.

Moreover, actuators, step motors, and solenoid valves in the electronic fuel injection system help improve the fuel efficiency and reduce the emissions.

The world of transportation is undergoing a revolutionary change with the introduction of self-driven vehicles.

Autonomous motor vehicles heavily depend on sensors, actuators, and processors to make crucial decisions on the road, ensuring the safety and comfort of their users.

The aforementioned points will help you appreciate the role that sensors and actuators play in the smooth functioning of self-driven vehicles.