Robotic mechatronic lunar rover system

Abstract

The invention relates to robotic, six-wheeled, mechatronic, modular systems with balanced transport chassis, designed to overcome natural obstacles and perform specific tasks. The essence of the invention lies in a balanced suspension system utilizing a suspended equilateral lever dyad with two driving wheels. The driving guide levers with wheels are connected through the equilateral dyad to create a new transport chassis design. The rear suspension transport chassis is equipped with drives for the rear wheels. Two half-shafts of the onboard transport chassis are symmetrically connected via intermediate bevel gears forming an inter-board differential for synchronization.

Description

[0001] Robotic Mechatronic Lunar Rover System

[0002] The invention relates to a robotic mechatronic lunar rover system featuring a balanced chassis with six degrees of freedom, encompassing the field of robotics.

[0003] The parallelogram-type suspended transport chassis consists of one rigidly connected, balanced link and four other links connected via joints. The suspension system, which ensures parallel wheel movement, is elastically linked to the balanced element. A primary drawback of this system is the inability of the elastic elements to maintain consistent contact with the surface, A differential mechanism installed on the platform connects the suspensions on both sides [1],

[0004] The solar-powered SOLE RO rover, developed in China, features six wheels. This rover incorporates chains in its design, which, while the wheels enable rapid movement, the chains facilitate mobility on difficult terrain. Despite having a paralielogram-type linkage chassis, the rover's platform does not maintain parallelism during motion, and the crank points do not align linearly [2],

[0005] In four-wheeled mechanisms, the suspensions are symmetrically positioned along the longitudinal axis of the platform and interconnected via differential mechanisms. This design reduces the chassis tilt angle on both the left and right sides but causes the wheels to lift off the surface due to reactive moments [3],

[0006] Four-wheeled rovers have a simple design. Each wheel is equipped with a mechatronic transmission and is remotely controlled, allowing the rover to adjust its speed •and wheel direction. A notable example is the Apollo Lunar Roving Vehicle (LRV), whose primary functions included surface exploration, conducting experiments, and sample collection [4], However, the rough terrain of the lunar surface complicated rover mobility. The rover's structure was insufficiently robust to operate effectively under these conditions, and the wheels' movement was limited on challenging terrain.

[0007] Robots sent to explore the surfaces of Mars and the Moon are typically designed with six wheels [5], Each side has three wheels, and differential mechanisms link the left and right suspension systems. In the "rocker system," a link is connected to the rear wheel via a joint and to the platform via a second joint. On the suspension's left side, a sevenlink “bogie system" with two guiding wheels is connected to the platform by a joint. The main disadvantage of this mechanism is the excessive number of links.

[0008] Patent [6] presents a six-degree-of-freedom mechatronic rover system. In this rover, the bogie system is based on the P. Chebyshev mechanism. In the two-loop, seven-link mechanism, wheels located on the sliding arms are equipped with mechatronic transmissions. The bogie system is balanced by the rocker system, together forming the suspension system. The left and right suspension systems are interconnected via a differential mechanism. The prototype's shortcomings include the bogie system's two closed loops and the large number of links. The mechanism's closed loops also increase occurrences of wheel lift-off from the surface, and the platform's parallelism is not maintained during movement. The problem addressed here is the creation of a new bogie design. The new construction aims to be simpler, with fewer links and reduced weight, while maximizing surface contact.

[0009] The essence of th® invention is that the robot comprises two transport chassis systems. These balanced suspension systems consist of a front five-link guiding linkage called the bogie system and a rear rocker system. The bogie system includes two arms with three joints each, whose centers are connected to the outer joints of another two- link, three-joint arm. Each sliding arm is equipped with motorized wheels tracing linear trajectories. Motorized wheels are also installed on the rear rocker suspension links to regulate bogie movement. The bogie and rocker together form the suspension system, and the left and right suspensions are symmetrically arranged along the platform's longitudinal axis and interconnected via a bevel gear differential mechanism.

[0010] The six-wheeled robotic mechatronic rover system consists of two transport, chassis (bogie and rocker systems) on the right and left sides, each with a five-link guiding linkage, a differential system, and platform-mounted components. The robot is intended for use in the military industry as well as for research on the surfaces of Mars and the Moon.

[0011] Problem: The synthesis problem of the guiding five-link mechanism with two degrees of freedom requires the sliding arm points to trace linear trajectories.

[0012] Result: A kinematic structure in the newly synthesized bogie system of a balanced six-degree-of-freedom chassis robotic mechatronic lunar rover system is proposed. The new design features the kinematic synthesis of two guiding five-link systems, and the left and right chassis are connected via a bevel gear transmission on half-axles. This system maintains platform parallelism during the mechanism's movement and regulates chassis motion. Innovations in the new bogie system include:

[0013] • Reduction of non-suspended closed loops from three to two,

[0014] ® A decrease in joint count from eight to five,

[0015] ® Reduction of moving links from six to four,

[0016] • Simplification of the mechanism construction and weight reduction.

[0017] Both the front and rear wheels of the robotic system are equipped with mechatronic transmissions. The suspension systems are connected to the platform via pivot joints. Overall, the six-wheel mechanism had balanced suspensions symmetrically arranged along the longitudinal axis on the right and left sides, interconnected by a bevel gear differential mechanism on half-axles.

[0018] The mechatronic robotic system achieves speeds of approximately 0.2 m / s. Each suspension's five-link guiding system is equipped with elastic elements serving as shock absorbers. These elastic elements regulate the spacing between links during motion.

[0019] The suspension system is connected via joints to the guiding five-link system consists of sliding arms. This design ensures that when encountering obstacles, the mechanism maintains platform balance and prevents loss of wheel contact with the surface. Figure list:

[0020] Fig. 1 ~ Structural scheme of the robotic mechatronic lunar rover system

[0021] Fig . 2 - Motion scheme of the left transport chassis of the robotic mechatronic lunar rover system

[0022] Fig. 3 •••• Motion scheme of the right transport chassis of the robotic mechatronic lunar rover system

[0023] Fig. 4 —Constructive scheme: of the six-wheeled robotic mechatronic lunar rover system Fig . 5 - Constructive scheme of the eight-wheeled robotic mechatronic lunar rover system Fig. 6 - General view of the robotic mechatronic lunar rover system

[0024] The platform (1) of the mechanism is supported on the half-axle pads (4,5) of the half-axles (2,3). The mechanism with 2 five-link guiding linkage systems and is equipped with mechatronic transmission front wheels (6,7), a single-arm balance link (8,9), middle wheels (10.1 1 ;. and rear wheels (12,13). The platform is connected by a synchronizing bevel differential mechanism (14). This design ensures balanced movement of the mechanism.

[0025] The robot operates as follows: upon encountering any obstacle, the front ’wheels (6,7) continue to move in the vertical direction, preserving their fundamental linear guiding property. The platform's support on the pads (4,5) maintains horizontal orientation and prevents displacement of particles on the platform. The synchronizing mechanism: located on the half-axles (2,3) connects to the left and right suspensions and transmits rotational motion through the associated bevel differential mechanism (14). This differential ensures stable platform positioning during motion and synchronous rotation of wheels.

[0026] The main advantage of the invention lies in the reduction of structural complexity: the number of non-suspended closed loops is reduced from three to two, the number of links, from seven to five, and the number of joints, from eleven to eight. This design increases the mechanism's weight, a critical performance parameter.

[0027] In summary, the invention simplifies construction and reduces weight, enabling uninterrupted surface contact andi maintaining platform parallelism during movement.

[0028] An eight-wheeled variant of the raver is also proposed, where both the front and rear transport chassis are equipped with bogie systems.

[0029] References

[0030] 1 Benea# H.E, FpoMoa B.B. M yjp. He3aawcwMaH SanaHcwpuaA noasecKa xoneca TpaHcnopTHoro cpeACTaa co BCTpoeHHbiMH B Koneca .mwarenAivm AC CCCP 2760 76 MrikBGOG 11 / 20 BM Nel 8 26.05.1970

[0031] 2. SOLERO: Solar-Powered Exploration Rover, S. Michaud et, al. 7th ESA Workshop on Advanced Space Technologies for Robotics and Automation "ASTRA 2002" ESTEC Npordwijk, The Netherlands, November 19-21 ,2000

[0032] 3. Kucherenko V, Bogatchev A, Winnendael M, Chassis Concepts for Exo Mars Rover Pros 8th ESA Workshop on Advanced Space Technologies for Robotics and Automation (ASTRA) ESTEC Noordwijk, The Netherlands. 2004

[0033] 4. David R. Williams, The Apollo Lunar Roving Vehicle, , ,

[0034] 6. Rasim Alizade. Structural synthesis of Robot Manipulators by using Screw with Variable Pitch. Universal journal of Mechanical Engineering USA. 7(2), (2019), SO- 63

[0035] 7 Alizade, R i, and et.al. Patent 12023 0092 <Robotta§d!rrlnus mexatronik modal sistemi> Baku, Azerbaijan. 26.12,2023 i

[0036] Azerbaijan Technical University

[0037] Rector Valiyev Vilayat

Claims

ClaimsRobotic Mechatronic Lunar Rover System1. A robotic mechatronic lunar rover system comprising two transport chassis symmetrically arranged along the longitudinal axis of the robot on the left and right sides, interconnected by a bevel differential mechanism, equipped with six wheels driven by mechatronic transmissions, characterized in that the system includes two five-link steering mechanisms, wherein the centers of a slider-crank system comprising two links of length 2b and three rotary joints are connected to the end joints of another slider-crank system comprising two links of length b and three kinematic rotary pairs, the upper and lower joints of the resulting five-link steering mechanism are connected via springs, thereby reducing the number of nondependent closed loops in the bogie system from three to two, the number of moving links from six to four, and the number of joints from eight to five, simplifying the mechanism structure and reducing its weight.

2. The robotic mechatronic lunar rover system respectively claims 1 , is characterized in that the rover comprises a total of eight wheels, and both the front and rear parts of the transport chassis are equipped with bogie systems. inventors: Valiyev Vilayat MammadAlizade Rasim IsmailHuseynzade Konul RufatAzerbaijan Technical UniversityRector t

Images