The development of a gearless spherical robot addresses the limitations of traditional wheeled and legged robots in scenarios involving collisions with the ground or other objects while throwing or maneuvering. This innovation introduces a dual-pendulum mechanism that enhances stability, maneuverability, and robustness, while eliminating the vulnerabilities associated with gears. The robot's unique design allows it to be throwable, with a protective hull that shields internal components from environmental hazards. Featuring a compact form, precise control, and dynamic stability achieved through an optimized ratio of moments of inertia, the robot supports autonomous, semi-autonomous, and remote-controlled operations. It is designed for diverse applications, including security, planetary exploration, surveillance, environmental monitoring, and search & rescue, ensuring reliable performance in challenging terrains.
Figure 1. Spherical robot (isometric view)
To develop a spherical robot as an alternative to conventional wheeled and legged robots, offering enhanced inner component protection, improved dynamic stability, low rolling resistance, and the ability to move in any direction - making it well-suited for surveillance in indoor environments. Despite these advantages, spherical robots face significant challenges in modeling, stabilization, and path following, which this design aims to overcome. Several methods have been developed for common designs of spherical robots. These designs include single wheel, internal weight, car, and single pendulum as actuators, but these approaches have various limitations.
- Gearless Design: This innovation avoids gear-related issues, enhancing performance in rough environments.
- Dual-Pendulum Mechanism: The unique shape of the pendulums increases the ratio of moments of inertia, allowing for precise control, dynamic stability, and improved maneuverability, while eliminating the need for gears that can fail in harsh environments.
- Throwable: It has a compact design with a polycarbonate hull that houses all electronics within the protective hull. This enables the robot to be throwable and withstand impacts even if it falls from a height or is thrown through obstructions.
- Compact and Miniaturized: The compact design allows for a smaller robot size without compromising functionality.
- Robust Construction: The spherical hull protects internal components from damage and environmental factors like dust, chemicals, and water.
- Versatile Operation Modes: It supports autonomous, semi-autonomous, and remote- controlled operations.
- Dynamic Stability: It has higher dynamic stability – enhanced by the special shape of the pendulums, increasing the ratio of moments of inertia.
The gearless spherical robot prototype features a robust design with a protective hull (190 mm diameter, 3-4 mm thickness). It includes dual mild-steel pendulums (193 grams each), a 5 mm thick acrylic yoke plate, Hitec HS-225MG servo motors for rolling, and Dynamixel AX-12 digital servos for pendulum motion. Powered by a 1300 mAh, 7.4V LiPo battery, it uses an Arduino Uno microcontroller for control, and an Xbee transceiver for wireless communication. The design ensures durability and stability, suitable for rugged environments.
The functionality and all major elements of end use, with remote controlled operation, have been achieved, along with the GUI development.
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This technology has applications in security and surveillance, especially in tactical scenarios requiring quick, stealthy deployment. Spherical robots can be thrown into buildings or tight spaces to gather real-time data, reducing risk to personnel. Their ability to navigate narrow gaps and flat surfaces enhances the efficiency and safety of surveillance in complex environments.
- Surveillance and Security: This device is suitable for monitoring in residential, commercial, and public environments such as homes, hotels, and malls. It allows remote inspection of areas and designed to withstand collisions in the process.
- Tactical Reconnaissance and Room Intervention: It facilitates real-time situational awareness in urban operations. It is useful for room intervention scenarios where the robot can be thrown or rolled into confined or potentially dangerous spaces for safe inspection.
- Real-Time and Dynamic Monitoring: It enables environmental observation in hard-to-reach places, such as under furniture or inside tight spaces.
- Toy and Entertainment Industry: It is adaptable for use as durable, remote-controlled toys designed for impact and collision-based play, enhancing engagement and user interaction.
Geography of IP
Type of IP
202223063422
543961