How Does a Speed Sensor Work?

Naomi O'Colman

How Does a Speed Sensor Work

How Does a Speed Sensor Work

A speed sensor is a device that measures the speed of an object. With the right sensors, it can determine the speed of cars on highways, planes flying through the sky, or even boats on lakes. In this blog, I’ll explain how does a speed sensor work on a car.

Speed sensors are not only used to measure velocity but also acceleration and rotations. So if you want to know how a car gets from 0-60 mph in 3 seconds flat, just put an accelerometer at each corner of that vehicle and use data taken from this machine to calculate its speed.

You can also use a speed sensor to measure the angular speed of a car. A car traveling around a race track will have speeds from 0º to 360º per second, while a ball thrown in the air by an athlete might have sped up to 1,200º/second. In all these cases, you want to measure the speed of your object or that of its rotation.

Devices Used To Measure The Speed

The first step is to get an accurate reading of how fast your object goes. In a car, there are several different ways to get the desired results.

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The first is a speedometer. In this device, a needle rotates around a dial that is marked with numbers from 0 to 150 mile per hour. As the car travels faster, this needle moves faster and points to a different number on the dial.

This dial is, however, prone to different kinds of errors. The needle can be blocked by a tire or by a block or gap in the road, so it doesn’t always point to the right speed. Another problem is that the gauge itself has a certain amount of torque and needs to be balanced. The last problem with this gauge is that it’s no longer at the center of the vehicle, so it doesn’t give you a true space-time measurement of your car’s speed.

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Around the outside of your car, you’ll find a wheel that’s divided into different little sectors. Each sector indicates a different speed to the driver. This wheel is also power-dependent, meaning that as your car loses power, it will drop faster.

ABS System

Another way to measure the speed of your vehicle is called an ABS system. By using this system, you can measure how fast your wheels are spinning so that you can control them more precisely through braking and speeding up.

The speed sensor works in the following way: When something goes around a wheel, it creates a magnetic wave. This wave moves away from the wheel and hits the sensor, which measures how fast it comes in. This measurement is used to calculate your speed.

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Types of Sensors

But how does this working mechanism fit into the car? It’s usually installed in front of your wheel, right beside your vehicle’s ABS system. There are two main types of sensors, an inductive type and a capacitive one.

Inductive Sensor

The inductive sensor is usually used with high-performance engines because the waves produced by these engines are very fast, but it’s also more expensive. The capacitive type is cheaper and less accurate, but it’s much more sensitive to vibrations.

An inductive speed sensor can sense your car’s rotation speed, so you can use it to measure how fast your car goes around a track or around the planet. The unit is attached to the front of your vehicle and uses electromagnetic induction to detect motion.

Capacitive Speed Sensor

A capacitive speed sensor can sense your car’s rotation speed, so you can use it to measure how fast your car goes around a track or around the planet. The unit is attached to the front of your vehicle and uses electromagnetic induction to detect motion.

Both types of sensors are attached to the wheels and use a small electromagnet that’s sandwiched between two coils of wire. As the electromagnet is being moved from left to right, it creates a magnetic field, which is sensed by a sensor on the vehicle. The sensor converts the signal of this magnetic field into a digital reading of speed.

The overall use of a device that measures speed is simple: you just need to keep this device calibrated. The calibration process involves the movement of your car on an actual road and measuring its “true” speed.

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Speedometer Accuracy

The accuracy of a speed sensor is determined by the sensors system and materials and depends on factors such as outside temperature, air pressure, and barometric pressure. The fastest speed the device can measure is about 250 mph (402 km/h). A speedometer can also be broken down into two parts: a transmitter and a receiver.


A speed sensor is an electronic device that’s used to measure the speed of an object. You can use this device in your car, in your boat or even in an airplane. There are several different types of sensors, but the most usual one is the inductive type that works by counting magnetic waves produced by a car’s engine. This kind of sensor has some weaknesses, so there are also other types that are less accurate but more resistant to vibrations.