# What is an accelerometer?

Increasingly used in portable electronic devices, the accelerometer allows a new interaction with the machine. Much more than evaluating the relative position of the device and adjusting the cell phone’s display, the instrument that measures accelerations is opening up a range of innovative alternatives. But what are accelerometers based on? Better understand how it works and prepare for what it will offer us in the near future.

Physical definition

According to Newton’s first law: “Every body remains at rest until some external force acts on it.” The second law, on the other hand, defines the applied force as the product of the body’s mass by its acceleration. Therefore, by measuring the acceleration applied to a body (and its weight), it is possible to determine the force applied to it.

An accelerometer is nothing more than an instrument capable of measuring acceleration over objects. Instead of placing several dynamometers (instrument for measuring force) in different places on the object, a single accelerometer is capable of calculating any force exerted on it.

A rudimentary method to find out if a table is well aligned with the floor is to fill a wide-mouthed glass to the extreme with water and place it on the top. According to the slope of the water from the water at the edges of the glass, it is possible to determine which side of the table is lower. In fact, this inclination occurs because the gravitational acceleration is more present on the lower side of the glass, in turn, this is nothing more than an example of an accelerometer.

Now fill this same glass halfway and place it on a moving object, a skateboard or something like that. By pushing it forward, one side of the glass is fuller than the other due to acceleration, if you can calculate the angle of inclination of the water, you can determine the force applied. When remaining at rest (stopped or in motion) the water level stabilizes in the glass, a sign that no lateral force is acting on it.

Electric accelerometer

Even if you are willing to break your iPhone, you will hardly find any liquid leaking from inside. This is because the accelerometers of electronic devices are usually composed of silicon springs and electric current. Instead of measuring the angle formed by the water in the cup, the springs record the oscillation in the electric current to record the data.

The automobile industry has provided a great cost reduction of the instrument due to its large-scale use. In cars, the accelerometer plays an important role in controlling stability by calculating the forces that the vehicle is being subjected to, in addition to assisting in GPS orientation. In addition to being cheaper, the instrument occupies much smaller dimensions and is often found in cell phones and portable computers.

Electronic application

Since the iPhone innovated with the feature, cell phones, players and digital cameras abuse the automatic positioning of the image, change tracks or perform actions without any button being pressed. In a computer, for example, one of the functions of the accelerometer is to prevent the hard disk from being damaged during a fall, stopping the HD during sudden movements.

But it is in games that this feature has been more explored, like the Nintedo Wii controller, interactivity in games is on the rise thanks to this instrument. From simple apps that simulate the movement of a lightsaber to car steering wheels in realistic titles, playing a game has taken on a new meaning with it.

Doodle Jump: simple concept, but able to explore the accelerometer in an exemplary way. Control a bouncing guy who doesn’t want to fall into life, guess how you control your jumps.

Crash Bandicoot Nitro Kart 3D: very intuitive and completely addictive casual racing game. Bombs, nitro and other funny items are allowed in this race with crazy characters.

Rolando: dynamic and extremely fun puzzle where your objective is to guide a group of nice balls through the scenery. Physics laws mix with funny properties of each of the creatures.

Real Racing: if other racing games value chance, here competitiveness is much more fierce. Realistic tracks are available to both novice pilots and those looking for an advanced simulation in multiplayer matches.

But is this necessarily a good thing?

Even though you are adept at involuntary movements with a joystick in your hand, it is much more common that you grew up pressing buttons to perform actions on your game screen than moving your arms to the side. Some of the owners feel embarrassed to be caught during their contortion during the waiting time of a queue.

If on the one hand the interaction with the devices gains new possibilities, on the other hand the lack of precision of some games leaves something to be desired. The development of games for laptops that exploit this feature is still relatively new and, among mistakes and successes, many games end up being frustrating for not exploiting the accelerometer in the most appropriate way.

The fact is that games and applications tend to improve their application and that this device will gain more accuracy in the coming generations. Imagine a basketball game, where you see the basket on the device’s display and simulate throwing your cell phone in place of the ball. Or even an application where you play beach discs with your dog in a similar way.

Another extravagant feature of little use or a trend in electronic devices? What do you think about the application of the tool that measures accelerations in cell phones and computers?