FCX24 Lemur – Reverse Engineering and Improvement

This project involved complete disassembly, 3D modeling, and mechanical analysis of the FMS FCX24 Lemur 1:24 RC Car.
The work included detailed studies of its chassis, drivetrain, suspension, and steering systems using Fusion 360 and ANSYS to explore real automotive dynamics on a miniature scale. Finally, to prevent rear-wheel slip our team designed and tested a custom-damped suspension.

Key takeaways:

• Achieved 3.3× torque difference between gears via two-speed transmission analysis.
• Verified chassis strength (>250 N vertical load capacity) and impact safety through simulation.
• Designed and validated a new damper (18 Ns/m) reducing slip and improving traction under incline conditions.

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Introduction

Analyzed the FCX24 Lemur RC car to understand real-vehicle dynamics using an accessible small-scale platform.

Analysis

Conducted structural and dynamic analysis on chassis, suspension, steering, and drivetrain using CAD and simulation.

Chassis

Simulated horizontal and vertical loads in Fusion 360 and ANSYS; chassis withstood > 250 N vertically with minimal deformation.

Suspension

Modeled spring–damper behavior and measured stiffness/damping values (k₁ = 2141 N/m, c₀ = 20 Ns/m) for optimal ride stability.

Steering & Drivetrain

Calculated gear ratios and torque multipliers (22.3× low-gear vs 6.7× high-gear); confirmed inverse relation between speed and torque.

Improvement

Tested fabricated improvements, including a rear-biased suspension with custom-viscosity oil (2010 cSt) designed to reduce wheel slip and enhance traction.

Report