Ever wondered about the hidden data your car generates as you drive? With a car scanner and Android Auto, you can tap into a wealth of information and even calculate interesting metrics like your car’s elevation profile. This article explores how a simple OBD car scanner and a bit of physics can reveal fascinating insights about your vehicle’s performance.
Turning OBD Data into Elevation Estimates
Using an OBD car scanner app like CarScanner, coupled with the power of Android Auto, allows you to record real-time data such as speed, power, and distance traveled. This data, combined with physics principles, can be used to estimate the elevation profile of your drive. The process involves calculating the energy balance for each time interval.
By estimating the power required for changes in kinetic energy, air resistance, rolling resistance, and drivetrain losses, and comparing it to the actual recorded power, we can attribute the difference to changes in gravitational potential energy, effectively calculating elevation change.
Refining the Calculation with Key Variables
While the concept is sound, achieving accurate results requires careful consideration of various factors. The accuracy of the elevation calculation heavily relies on input parameters like the coefficients of aerodynamic drag (CdA) and rolling resistance (Crr). Initial estimates for these values need to be refined.
One effective method involves driving a loop circuit multiple times. If the calculated “virtual elevation” doesn’t return to the same level at the same point on each lap, adjustments to the CdA and Crr values are needed until consistency is achieved. This iterative process helps fine-tune the model and improve the accuracy of the elevation profile.
For instance, in the example illustrated above, the following inputs were used:
- Drivetrain Efficiency: 85%
- Air density: 1.205 kg.m⁻³
- Mass: 1,770 kg
- Crr: 0.017
- CdA: 0.80 m²
Challenges and Future Improvements
While promising, this method isn’t without its challenges. The raw data format from apps like CarScanner can require significant processing, potentially introducing errors into the calculations. Further experimentation with data processing techniques is necessary to enhance accuracy.
Beyond elevation profiling, this approach offers a potential avenue for estimating a car’s aerodynamic properties. With refinements to the data handling and calculation methods, a car scanner paired with Android Auto could become a powerful tool for understanding your vehicle’s performance in greater detail. Using a loop circuit for calibration offers a practical way to refine the accuracy of these calculations. This approach transforms a simple car scanner into a sophisticated diagnostic tool, unlocking hidden insights into your vehicle’s performance and aerodynamics.
