linear encoder

What is a linear Encoder?

A linear encoder is composed of an optic encoder capable of measuring angular movements and a coil that allows linearizing them, in this way, any linear movement can be measured.

It is a very useful tool when it comes to evaluating the work an athlete does in the gym. Thanks to different variables measured by the device (displacement, velocity, acceleration, power …) it is possible to know daily and without needing to fatigue the athlete his fitness with a very high precision.

In this way, among many other things, you can know how much weight you must train the athlete that day to get the maximum match to the weight session. But not only that, you can also know the fatigue that that athlete accumulates, controlling it, thus avoiding possible injuries in his specific sport.

Why use a linear encoder?

The encoder allows knowing the athlete´s 1RM, or the state of body in that same session. It is a very precise way of knowing objectively how the athlete is without the need to test with very high loads that can excessively fatigue or even injure him. It allows you to have great control of what is happening within the weight session, in order to be able to take the maximum advantage and meet the planned objectives.

Which athletes benefit from its use?

Practically any athlete will benefit and will improve in their specific sport by working with weights.

That’s why it does not matter what sport you’re into, if you train in the gym it’s going to be very useful.

Among our clients are:

Swimmers, tennis players, paddle players, wrestlers, boxers, professional BMX competitors, professional soccer players,

Linear encoder or Accelerometer?

Many ask us what device to buy. At a time when accelerometers were becoming fashionable, we decided to develop the Speed4lifts linear encoder because without a doubt it is the most PRECISE technology to monitor the training, and we do not say it, there are several validation studies that show how the accelerometers today lack the minimum precision to estimate 1 RM or quantify fatigue correctly.

What advantages has Speed4lifts compared to other linear encoders on the market?

Speed4lifts was developed taking into account both our needs and that of several coaches we knew. We knew that the ideal was to have a linear encoder, but what was on the market was extremely expensive for us (several thousand euros) and also were not portable (require a laptop).

For that reason we launched to develop Speed4lifts a completely portable encoder (includes a screen that shows the data in real time, and connects to our Android* and iOS applications in real time showing a large amount of data), scientifically validated and very economical compared to other devices.

* We have temporarily paused updates on Android. We apologize for the inconvenience. 

How much does Speed4lifts weigh?

Its weight is 365g

How is it fixed to the ground?

In the base it has 6 magnets to support it on an iron disk and prevent it from moving.

What is the length of the string?

The length of the rope is 2m. But in case you need more height you can place on some object or you can use a rope hooked to the carabiner to make an extension.

What is the minimum path that it detects?

One of the advantages of Speed4lifts is that it adapts to your needs. Thanks to the filter that we have incorporated, you can decide from how many centimeters you want the encoder to detect a repetition, in order to register the surveys and discard small movements, such as removing the bar from the rack. The filter comes by default at 20cm, the lower movements discard it, but you can change it without problem. Watch this video to know how to modify it.

What is the sampling frequency?

100Hz Thanks to a subsequent filtering of the serial and interpolation rods, we achieve a very high precision even for very fast lifting.

What minimum velocity can it register?

In exercises such as bench press we have reached velocities of 0.04m / s and in deadlift we have managed to record repetitions of 0.1m/s.

What maximum velocity can it register?

6m/s. It is very likely that you will never reach those velocities in any movement. A punch for example, usually recorded at velocities of 4m/s, you will hardly find a movement in the gym that is faster than a punch.

What variables are measured?

For the moment, theapp shows the distance (cm), average propulsive velocity (m / s), maximum velocity (m/s) and power (W). But in future updates we will incorporate new variables.

Is it completely portable?

Yes, if you do not want to, you do not have to use your mobile phone, with the built-in screen you can see the route, the average propulsive velocity, the maximum velocity, the repetition in which you are and the remaining battery.

Does it require a mobile application?

No, but it is very useful to get the maximum match. You can save your records, estimate to 1RM, know with what weight to train, know the fatigue that you accumulate…

What is the password to connect to the encoder?


How long does the battery last?

The battery lasts approximately 8-10h.Approximately 2 weeks of training.

How do I know how much battery is left?

On the encoder´s led screen, at the top left you can see% of the battery.

How do I charge the device?

The encoder has a micro USB type b connector, and next to it, it includes a cable that can be connected to both a computer and a 5V transformer.

Next to the micro USB connector there is a red LED that flashes while charging. The charging time is +-2h

Can I turn off the encoder while I rest?

Of course! You will save battery. But the data that is on the OLED screen of the encoder will be lost. On the contrary, you will not lose the data that is in the mobile application.

What data shows the OLED screen?

With the built-in screen you can see the route, the average propulsive velocity, the maximum velocity, the repetition in which you are and the remaining battery.

How do I use the buttons on the screen?

With the buttons below the screen you can navigate between different exercises and between repetitions of the same series. In this video it is shown in more detail:

Can the rope break due to wear

The outer shell is made of ABS, which makes it resistant, but we cannot guarantee that nothing will happen to you. If it falls to the ground it can break, and if a bar or a disc falls on top of it, too.

Does it break if it falls to the ground?

The outer shell is made of ABS, which makes it resistant, but we cannot guarantee that nothing will happen to you. If it falls to the ground it can break, and if a bar or a disc falls on top of it, too.

Can it get broken if I do weightlifting?

You can do weightlifting with it, but you have to be careful that the bar does not crush the encoder.

Where and how do I place the encoder?

The ideal position is when doing a repetition, the encoder rope comes out and enters in a linear way without turning or changing its angle with respect to the ground. Even so, if you always place the encoder in the same position, it will always measure you in the same conditions so there is no problem.

Velcro strap?

The encoder also includes a neoprene bag, a Velcro strap so you can hook it to the bar.

Does it just measure vertical movements?

No. Does it measure any movement as long as it is linear, if the string only rotates and does not come out and/or enters the encoder, it will not measure anything.

How do I transport it?

The encoder includes a neoprene bag to protect it.

Can I leave it in the sun or at high temperatures?

It is not advisable to leave it in the sun because it can reach high temperatures and suffer damage. Do not expose it to temperatures above 40 C.

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