I developed and executed a three-stage procedure, along with the help of two partners, to accurately determine the Center of Gravity (CG) coordinates (x, y, z) for the AER25 vehicle. This project was foundational for the Vehicle Dynamics team. The final calculated CG values were critical for ensuring the CG remained low to the ground for maximum performance and for validating the car's roll stability during the demanding FSAE EV Competition tilt test.
The final verified CG z was 14 inches, which represents a 16.7% correction from the previous team's measurement of 12 inches. This variance was not due to error, but due to procedural refinement. Mandated spring locking and increasing the angle of elevation contributed to this.
My contribution was documenting the procedure, ensuring safety measures were met during the experiment, and taking measurements during the tilt test. I then processed all data into the final, usable 3D coordinates. The work strengthened my application of fundamental engineering mechanics — static force equilibrium and moments.
Success in this procedure depended on data precision and process control. We encountered technical obstacles inherent to testing a vehicle on a flexible suspension system.
Suspending the CG vertically required the suspension to be completely locked prior to elevating the front axis, to ensure the geometry of the car does not shift and change where the center of gravity lies.
The suspension was completely locked prior to elevating the front axis in order to ensure that the geometry of the car does not shift and thus change where the center of gravity lies.
Obtaining a 15-20 degree incline of the vehicle for an accurate vertical CG measurement required a reliable, safe elevation method.
The front axle was elevated to 15 degrees by elevating the front tires onto tall wooden blocks. This high elevation is critical because maximizing the angle minimizes the sensitivity to measurement noise from the scales.
The project's objective was to apply the principles of static equilibrium and moment analysis to analyze the vehicle's mass distribution. CG x and CG y were obtained from four-corner scale readings on level ground:
CG z was determined by performing the tilt test, which involves elevation of one axle to an incline and measuring the corresponding load transfer:
This project was foundational for the Vehicle Dynamics team at AER. Accurate CG data is required for suspension tuning, weight distribution analysis, and passing the FSAE tilt test. The previous team's measurement had not accounted for spring locking during the tilt, which introduced error. By refining the procedure and documenting it thoroughly, we gave future teams a reliable baseline to build from.
The work strengthened my understanding of static mechanics, experimental procedure design, and real-world data collection on a competition vehicle.