The Remotely Operated Rough Terrain Vehicle (RO-RTV) project focused on the design, fabrication, and testing of a small-scale car capable of handling uneven and off-road surfaces. The vehicle was equipped with a multi-gear transmission system providing two forward gears and one reverse gear to effectively control speed and torque. A custom suspension system was developed to absorb shocks during rough terrain operation, while a steering system was designed for stable maneuverability. The complete vehicle was modeled in CAD, with components machined, 3D-printed, and fabricated for assembly. The project successfully demonstrated a functional prototype that integrates power transmission, suspension, and steering for efficient remote operation on rough terrain.
Introduction
The need for remotely operated vehicles (ROVs) capable of traversing uneven and rugged terrain is growing in both research and industrial applications. Such platforms are useful in hazardous environments, disaster response, exploration, and defense operations. The objective of this project was to design and build a small-scale rough terrain vehicle with remote operation capability, focusing on mechanical systems such as power transmission, suspension, and steering. Emphasis was placed on durability, maneuverability, and adaptability to rough surfaces.
Powertrain and Transmission System
The vehicle was powered by an electric motor, which initially operated at full speed without modulation. To improve performance and provide better control, a custom transmission system was developed. The gearbox featured three gears: two forward gears and one reverse gear, allowing the vehicle to operate at different torque and speed ranges. The lower forward gear provided high torque for climbing obstacles, while the higher gear enabled faster travel on smoother terrain. The reverse gear facilitated maneuvering in confined or difficult environments.
Suspension System
A key requirement for rough terrain operation was the ability to absorb shocks and maintain stability. A suspension system was designed specifically for this purpose.
Front Suspension: The front suspension was more complex to ensure independent motion of both rear wheels. It consisted of two U-shaped suspension arms mounted to the chassis via ball joints, allowing rotational freedom. A central spring and damper system was placed between the two arms, enabling each rear wheel to move up or down independently while still sharing load distribution. This configuration ensured better stability on uneven surfaces and reduced the transfer of shocks from one wheel to the other.
Rear Suspension: The rear suspension used tubular housings with springs inside. Bearings were placed at the bottom of the tubes to allow smooth vertical motion of the suspension rods. The tubes were supported at the top of the chassis, holding the springs in compression and allowing controlled movement when the wheels encountered bumps. This design provided a simple yet effective shock absorption system for the rear axle.
The suspension minimized vibration transfer from the ground to the chassis, thereby protecting sensitive components and ensuring smooth vehicle motion. The geometry of the suspension was optimized in CAD to provide adequate travel while maintaining compactness and structural strength. During testing, the suspension proved effective in reducing jolts and enhancing ride stability over uneven surfaces.
Steering Mechanism
To provide precise control of the vehicle, a custom steering system was designed and implemented. The system allowed reliable maneuverability over varying terrain conditions while maintaining stability during sharp turns. Steering linkages and joints were carefully fabricated to ensure robustness against repeated mechanical stresses. Remote actuation of the steering was integrated with the vehicle’s control system, enabling smooth directional control during testing.
Design, Fabrication, and Assembly
The entire vehicle was first modelled in CAD software, allowing for optimization of dimensions, clearances, and integration of different subsystems. Components were then machined, 3D-printed, or fabricated depending on functional and structural requirements. Metallic parts were machined for strength, while lightweight or complex components were 3D-printed. The fabrication process emphasized precision to ensure seamless assembly of the transmission, suspension, and steering systems. The completed prototype was successfully assembled and tested under various terrain conditions.
Results and Discussion
The assembled RO-RTV demonstrated strong performance in rough terrain environments. The transmission system allowed smooth gear shifts and provided flexibility between high torque and high speed operation. The suspension effectively absorbed shocks, resulting in stable operation on uneven ground. The steering system provided precise maneuverability, enabling controlled navigation. Limitations identified included battery endurance and further optimization of gear ratios for efficiency. Nonetheless, the vehicle proved capable of performing its intended functions and validated the design approach.
Conclusion
The Remotely Operated Rough Terrain Vehicle project successfully combined CAD design, mechanical fabrication, and system integration into a working prototype. The integration of a 3-speed transmission, suspension system, and steering mechanism enabled effective navigation of rough terrains. This platform demonstrates potential applications in exploration, surveillance, and hazardous environment operations. Future improvements could include advanced remote control electronics, higher capacity power systems, and sensor integration for semi-autonomous operation.