Welcome to the PAGAL LAB FAQ section.
Here you will find answers to the most common questions about the Inertia X1 tool, Swingweight measurement and the use of our Web App.
If you don't find the answer you are looking for, please don't hesitate tocontact us directly.
1.What is Swingweight and why is it important to measure it
Swingweight (or inertia) is a dynamic measurement that indicates how much resistance the racket offers when it is moved through a swing. Unlike static weight, it describes how “heavy” the racket feels to youwhile you hit the ball. A high value means more stability and power, but more fatigue; a low value means more manoeuvrability and arm speed.
Knowing the Swingweight is the only way to perform scientific and replicable customization. Adding lead tape to the head or the handle drastically alters the inertia, even if the total weight increases by only a few grams. Without measuring it, you are just guessing. With Inertia X1, you can design the modification and instantly verify the result.
It is fundamental. Measuring before provides your exact starting point and allows you to understand by how many points you need to increase the inertia to achieve the desired feel. Measuring after is the only real verification: it certifies that the modification has produced exactly the value you were looking for, allowing you to correct or replicate the setup on a second frame with absolute precision.
The instrument Inertia X1
Inertia X1 is a precision torsional dynamometer. It utilizes two harmonic steel tension springs and an ultra-low friction ball-bearing suspension system. Measurement is performed by placing the racket on the instrument and initiating an oscillation. The oscillation period, which is directly proportional to the square root of the frame's inertia, is detected by the smartphone placed on the dedicated support. The installed app acquires raw data directly from the phone's physical gyroscopic sensors and, through a proprietary algorithm, calculates the exact Swingweight.
In our laboratory tests, we achieved an accuracy of better than ±0.3 kg·cm². However, it is important to note that this accuracy depends directly on the measurement conditions and the quality of the gyroscopic sensors in the smartphone used.
For further details, see the article:Precision and Testing: How Inertia X1 is Tested
The most important factor for accuracy is the leveling of the instrument. If the rotation axis is not perfectly vertical, the force of gravity introduces a force component that adds to that of the springs, altering the oscillation period. We have verified that a 0.5° variation in inclination generates an error of approximately 1.06%: for a racket with a SW of 320 kg·cm², this translates into approximately 3 points of inertia.
However, this effect can be compensated for: in one of our laboratory tests, we leveled the instrument with extreme precision, performed the calibration procedure, and took and saved a series of measurements. We then inserted a 1 mm shim under one of the feet to vary the axis tilt by almost 1°.
The measurements acquired after the alteration reported an error in some SW points, as highlighted above, but, once the calibration procedure was redone with the new setup, the measurements returned to those previously detected.
The app includes a digital spirit level on the calibration page, which allows you to check and correct any tilt by adjusting the levelling feet. Once the instrument is levelled within a ±0.5° range and the calibration procedure is complete, you simply need toDon't move it: as long as it remains in the same position, any residual tilt is incorporated into the calibration itself and does not affect the measurement accuracy. The instrument does not necessarily have to be perfectly level — it must bestable and calibrated in its position.
A second important factor is the support release technique. A sudden or excessively "accompanied" release can alter the initial amplitude of the oscillation. The app can automatically detect the presence of disturbances during the release phase and warns you about the reliability of the measurement via a dedicated indicator. With a few practice sessions, you will quickly learn the correct technique.
Inertia X1 is a precision instrument and must be treated as such. To function correctly and provide reliable data, it must operate under specific conditions:
Absence of Vibrations:During measurement, the surrounding environment must be still. Table vibrations or strong draughts can alter the oscillation of the torsional pendulum.
Stable PianoIt must be placed on a solid, rigid surface (a sturdy table, a workbench), not on soft or wobbly surfaces.
Calibration:Ultimately, the app simply measures the time it takes for the racket to complete one swing. If the environmental conditions described above are met, the measurement is accurate and consistent; at this point, the calibration process comes into play to transform the time value into your racket's swingweight.
There are two aspects to consider in the calibration process. The first is the procedure: the calibration must be performed carefully, under the same conditions in which the measurements will be taken, and by correctly positioning the calibration samples on the support. The second is the accuracy of the samples: the two inertial samples supplied with the instrument have individually measured inertia values associated with the instrument's serial number. They are the physical reference on which all calculations are based—the more accurate their known values, the more accurate the final result will be.
3. The Inertia X1 Software
No. Access to the app is obtained by scanning the QR code located on the underside of the instrument. In a single step, the smartphone recognises the device and automatically loads the calibration parameters specific to your unit.
The QR code automatically recognises the type of smartphone and directs each user to the most suitable version: oniPhone, the web app opens directly in the Safari browser – no installation required, no App Store steps. OnAndroid, the native app download is initiated, which directly accesses the hardware gyroscope sensor to ensure maximum measurement accuracy. In both cases, the app is always automatically updated to the latest version.
Absolutely not. You just need to scan the QR code once. This process installs the PWA on your smartphone and calibrates it specifically for theyoursInertia X1 tool. Once installed, the app will appear as an icon on your home screen, and you can launch it directly from there.
No, after the initial installation and calibration, the app works offline. You don't need an internet connection to take measurements and calculate the swing weight. The connection is only necessary for the initial scan and any future updates to the PWA.
The quality of your smartphone's sensors directly affects the accuracy of the measurement. The app requires a good-quality physical gyroscope and accelerometer. Low-end smartphones that use "virtual" sensors (emulated via software) are not suitable because they don't provide data with the frequency and precision needed to correctly time the oscillation.
For further information, please see the page:smartphone requirements
The process is immediate:
- Place the racket on the instrument (under the ideal conditions described above).
- Launch the PWA on your smartphone and place it in the stand cradle.
- Start the measurement from the app and start the oscillation.
- The smartphone detects the swing via sensors and, within seconds, calculates and displays the exact Swingweight.
For more information, visit our YouTube channel
4. Purchase, support and warranty
The purchase includes the ready-to-use Inertia X1 instrument, inertial samples for calibration, and access to the dedicated measurement web app with all its saving and database features. The calibration values of the supplied samples are associated with the instrument's serial number and are downloaded directly into the app.
Each instrument is individually tested and calibrated before shipping; the package includes the Test Certificate generated by our Pagal Diagnostic Lab analysis software; the procedure consists of an accurate analysis of the data collected by the app during the execution of 10 consecutive measurements.
For more information on the testing procedure, please refer to thededicated article, contained in the technical area
Yes, Inertia X1 is covered by the 2-year legal guarantee of conformity for manufacturing defects.
If you encounter any problems with the tool or the Web App, you can write to us directly using the form on the contact page or by email at info@pagal-lab.com
The app has a function to save and export the acquired data that you can send to us for analysis and to solve any problems you are encountering.
We respond quickly to solve all your technical needs.
Yes, we ship throughout Europe. Shipping costs are not included in the price, and shipping times vary depending on the destination and will be calculated during the checkout process.Contact usfor more information on shipping costs and times to your destination.