Bolted Motor Mount

Objective: Engineer a structural interface to secure the powertrain's electric motor (240 Nm peak torque) to the tubular spaceframe chassis.

Constraints:

DFM: Component restricted to planar geometry for rapid waterjet manufacturing (0.5" 6061-T6 Aluminum).
Strength: Must be able to resist 2.37 kN of compressive load.
Reliability: Minimum Factor of Safety (FOS) of 2.0 required.

The mount integrated into the vehicle assembly, interfacing between the electric motor and rear chassis subframe.

Prior to CAD modeling, I quantified the loading conditions using first-principles analysis.

Global Equilibrium: Resolved motor torque and chain tension into a net radial reaction force of $2.37$ kN via Free Body Diagrams.
Vector Analysis: Developed a parametric Excel calculator to perform a Bolt Group Analysis. This tool resolved shear vectors for the eccentric 8-bolt pattern ($0^\circ$ to $300^\circ$) to identify the critical load case for fastener sizing.

The calculation of loads on each motor bolts.

Utilizing SolidWorks, the geometry was refined through 7 iterations focused on maximizing the stiffness-to-weight ratio.

Mass Reduction: Reduced component weight by $9\%$ (from $0.8$ lbs to $0.72$ lbs) through manual topology optimization, removing non-structural mass while reinforcing primary load paths.
Geometry: Maintained a strictly 2.5D profile to eliminate CNC milling requirements and reduce manufacturing lead time.

FEA of the latest 6 iterations. The shape changed to accommodate different motor’s placements and bolt clearances.

The design was validated using ANSYS Mechanical (Static Structural) to verify performance against yield.

Simulation: Applied calculated reaction forces as remote loads distributed across bearing surfaces, with fixed supports at chassis mounting points.
Results: Simulation confirmed a minimum Factor of Safety of $2.90$, providing a robust margin for dynamic shock loading.
Fastener Selection: Selected AN3 aviation bolts based on the calculated peak shear vector, ensuring compliance with competition regulations.

The final design was waterjet cut from 6061-T6 plate and successfully integrated into the vehicle, meeting all mass and stiffness targets.

Role: Mechanical Design Engineer
Analysis: Rigid Body Dynamics, Bolt Group Vector Analysis, Static Structural FEA.
Key Metric: $9\%$ Mass Reduction achieved while maintaining $2.9$ FOS.
Tools: SolidWorks, ANSYS Mechanical, Excel, SpaceClaim.

Rear Differential Mounts