Most motion trackers are based on IMUs capable of 9-axis tracking. However, IMU-only trackers cannot accurately measure the activity of muscles and joints, which are the core of exercise, and require an unnecessarily many sensors for measurement, which is cumbersome and expensive.
Fitness tracking is NOT just motion tracking. The Keefit team has developed an innovative tracker optimized for exercise from an exercise mechanics point of view. The Keefit Sensor integrates a 9-axis IMU sensor with patented technology that accurately measures contraction-relaxation of joints and muscles, allowing you to track your workouts effectively and efficiently at minimal cost. Keefit is the world's first and the only system that can accurately measure arm or leg movement with just one sensor. Keefit Sensor is made of thin and flexible silicone material, so the user does not feel discomfort even with vigorous exercise.
The 9-axis IMU inherent in the Keefit Sensor uses a state-of-the-art chip from a global lead manufacturer to provide the highest level of tracking quality in existence. Please refer to the Appendix at the bottom of the page for detailed tracking quality.
Another challenge that a fitness tracker has to solve is beauty. Keefit Sensor provides a beautiful design to be used as a fashion item. In addition, it can be used with the elbow and knee braces that many people are familiar with, so it is comfortable without being burdensome in appearance.
Keefit provides the world's lowest price, so anyone can use Fitness Tracker without worries. We offer a 4-piece set that can track all your arm and leg movements for $99. For more details, please refer to the price plan, which will be updated later.
Students or engineers researching IMU-based motion tracking can also develop their fitness software using the Keefit Sensor. See the Ecosystem page for details.
Heart rate measurement is the most basic of Fitness Tracking. Keefit supports real-time tracking of heart rate data through linkage with the Apple Watch. In the future, almost all heart rate trackers on the market will also be supported quickly.
Spec. | Unit | Value | |
---|---|---|---|
1 | Standard full range | [°/s] | ±2000 |
2 | Sensitivity | [LSB/g] | 16.4 |
3 | In-run bias stability | [°/h] | 10 |
4 | Bandwidth (-3dB) | [Hz] | 255 |
5 | Output noise density | [°/s/√Hz] | 0.007 |
6 | g-sensitivity | [°/s/g] | 0.1 |
7 | Nonlinearity | [%FS] | 0.1 |
8 | Scale factor variation | [%] | 0.5 (typical) / 1.5 (over life) |
9 | Sample Frequency | [Hz] | 800 |
10 | Resolution | [bit] | 16 |
Spec. | Unit | Value | |
---|---|---|---|
1 | Standard full range | [g] | ±16 |
2 | Sensitivity | [LSB/g] | 2048 |
3 | In-run bias stability | [mg] | 0.03 |
4 | Bandwidth (-3dB) | [Hz] | 324 (Z axis: 262) |
5 | Output noise density | [µg/√Hz] | 120 |
6 | Nonlinearity | [%FS] | ±0.5 |
7 | Sample Frequency | [Hz] | 800 |
8 | Resolution | [bit] | 16 |
Spec. | Unit | Value | |
---|---|---|---|
1 | Full scale | [Gauss] | ±8 |
2 | Total RMS noise | [mGauss] | 0.5 |
3 | Resolution | [mGauss] | 0.25 |
4 | Nonlinearity | [%FS] | 0.2 |
5 | Sample Frequency | [Hz] | 60 |
6 | Resolution | [bit] | 16 |