Executive Summary

In the automotive industry, achieving precise and repeatable wheel alignment is critical for optimizing vehicle performance, stability, and tire wear. Traditional methods of wheel alignment measurement can be time consuming and require expensive stationary equipment.

This page introduces and analyzes the Gyraline Platform, an innovative handheld tool designed to quickly measure wheel alignments in the field. We will specifically look at the similarity and precision of Gyraline’s camber and total toe measurements when compared to an industry standard stationary alignment machine.

Through rigorous testing and analysis, the precision of the Gyraline Platform has been characterized by a measurement range of +/- 0.020° at a 99% confidence interval for total toe measurements. This precision is well within the range of the most stringent industry dictated critical resolution of +/- 0.050°, and is similar to the tools currently trusted in the industry.

This study was conducted in a controlled environment by a professional, strictly adhering to the procedures outlined by both device manufacturers. Results are not guaranteed and may vary due to numerous factors.

Introduction

Wheel alignment is an essential process that ensures an automobile’s wheels are parallel to the vehicle’s centerline, or offset slightly within a specified range. Wheel alignment alters the vehicle’s handling characteristics and has a substantial effect on tire wear.

A wheel alignment can be modified by normal component wear, such as the natural wear on bushings, or inadvertently by impacts, such as from potholes and curbs. In order to correct out of range wheel alignment, a vehicle must have the alignment measured. A user then must adjust the suspension via the vehicle’s onboard adjustment hardware.

Purpose of Study

Traditionally, wheel alignment measurements are conducted on machines which include a vehicle lift, four image targets, and a camera assembly. These devices are large and stationary, commonly taking up an entire repair bay, and do not allow for mobile operation. Further, they have extended setup times to check each vehicle’s alignment. Gyraline is a newly developed mobile alignment platform that uses a specially cased handheld device and its onboard sensors.

This study looks to measure the repeatability and precision for total toe and camber of the Gyraline Platform alongside that of a calibrated industry standard alignment machine.

Methodology and Testing

The vehicle of choice for this testing was a 2023 vehicle with ~7,900 miles on the odometer with no known issues. 

The industry standard stationary alignment machine tested herein was owned and operated by an OEM dealership at the time of the study, and was recently calibrated. This alignment machine's sensors were removed in between alignment checks and new rolling compensations were performed for each test.

The Gyraline Platform tested herein was the public release of Gyraline DIY 2.00 running on a Gyraline calibrated Apple iPhone 13 Pro. The device was installed in an off the shelf production “Gyraliner DIY” which is the official Gyraline DIY phone encasement that allows for precise Gyraline DIY measurements.

Caster and Ackermann were not captured during this testing for the stationary alignment machine and Gyraline DIY due to time constraints.

The test procedure was conducted as follows:

Results

Total Toe

Averaged and corrected for one outlier, the industry standard stationary alignment machine found the total toe on the front axle to be 0.36°. Gyraline DIY, averaged and corrected for one outliner, found the total toe on the front axle to be 0.35°.

Averaged and corrected for one outlier, the stationary alignment machine found the total toe on the rear axle to be 0.35°. Gyraline DIY, averaged and corrected for one outliner, found the total toe on the rear axle to be 0.36°.

The stationary alignment machine range for total toe measurements at a 99% confidence interval was found to be +/- 0.016°.

Gyraline DIY’s range for total toe measurements at a 99% confidence interval was found to be +/- 0.020°.

Camber

Averaged and corrected for one outlier, the stationary alignment machine found the camber on the front left wheel to be -0.70°. Gyraline DIY, averaged and corrected for one outliner, found the camber on the front left wheel to be -0.76°.

Averaged and corrected for one outlier, the stationary alignment machine found the camber on the front right wheel to be -0.77°. Gyraline DIY, averaged and corrected for one outliner, found the camber on the front right wheel to be -0.79°.

Averaged and corrected for one outlier, the stationary alignment machine found the camber on the rear left wheel to be -1.41°. Gyraline DIY, averaged and corrected for one outliner, found the camber on the rear left wheel to be -1.59°.

Averaged and corrected for one outlier, the stationary alignment machine found the camber on the rear right wheel to be -1.48°. Gyraline DIY, averaged and corrected for one outliner, found the camber on the rear right wheel to be -1.50°.

The stationary alignment machine range for camber measurements at a 99% confidence interval was found to be +/- 0.056°. Gyraline DIY’s range for camber measurements at a 99% confidence interval was found to be +/- 0.105°.

Analysis

Comparing the data sets and results of the industry standard stationary alignment machine and Gyraline DIY, we see that the stationary alignment machine was slightly more precise than Gyraline DIY, but both measured the vehicle’s toe within a range of 0.05°, and camber within a range of 0.25° with a high degree of repeatability. Given the typical manufacturer specification range of 0.20° for toe and 1.00° for camber, Gyraline DIY is able to measure and display wheel alignment data with a high enough precision to determine whether a vehicle’s wheel alignment is within factory specification.

Further, comparing the values of the results we see that the stationary alignment machine's measurement for total toe front was 0.36° and Gyraline’s average value for total toe front was 0.35°. Similarly, the stationary alignment machine’s measurement for total toe rear was 0.36° and Gyraline DIY average value for total toe rear was 0.35°. Thus, the stationary alignment machine and Gyraline DIY produced measurement values overlapping within each other's range at a 99% confidence interval.

The reader should note that the true alignment of the test vehicle was unknown and neither the stationary alignment machine nor the Gyraline Platform are able to provide a measurement that allows for a determination of the absolute accuracy of any measurement. Analysis of the data is focused on the range between measurements of each of the respective tools and to each other.

The source of the above statements can be found in the following tables.

Conclusion

Through rigorous testing and analysis, Gyraline DIY has been found to be nearly as precise as a calibrated industry standard stationary alignment machine. While the stationary alignment machine was slightly more precise than Gyraline DIY, both measured the vehicle’s toe within a range of 0.05°, and camber within a range of 0.25° with a high degree of repeatability. Given the typical manufacturer specification range of 0.20° for toe and 1.00° for camber, Gyraline DIY is able to measure and display wheel alignment data with a high enough precision to determine whether a vehicle’s wheel alignment is within factory specification. Further, this precision is well within the range of the most stringent industry dictated critical resolution of +/- 0.050° for toe.

This study was conducted in a controlled environment by a professional, strictly adhering to the procedures outlined by both device manufacturers. Results are not guaranteed and may vary due to numerous factors.