Wheeled leg robot and driving method thereof

Abstract

The invention discloses a wheeled leg robot and a driving method thereof, and belongs to the technical field of wheeled leg robots, the wheeled leg robot comprises a vehicle body, thighs, shanks, wheels and two hydraulic control systems; the hydraulic control system comprises a hydraulic cylinder, a piston rod and a motor gear control system; a bearing cavity and a non-bearing cavity are formed inthe hydraulic cylinder; the piston rod separates the bearing cavity from the non-bearing cavity; a hydraulic control system controls the extension of the piston rod relative to the hydraulic cylinderor controls the included angle between the vehicle body and the thigh through a motor gear control system; and the other hydraulic control system controls the extension of the piston rod relative tothe hydraulic cylinder or controls the included angle between the thigh and the shank through a motor gear control system. According to the wheeled leg robot and the driving method thereof, overflow loss and throttling loss are avoided, the system power is saved, the transmission efficiency of a hydraulic system is high, the energy utilization rate is high, the buffering performance is good, and the service life is long.

Description

technical field [0001] The invention belongs to the technical field of wheel-leg robots, and in particular relates to a wheel-leg robot and a driving method thereof. Background technique [0002] The wheel-legged robot refers to adding wheels to the end of the robot legs. This kind of robot fully combines the advantages of wheels and legs. pass in a structured environment. Compared with the legged robot, it has a faster traveling speed in the road environment, so the research on the wheel-legged robot has received more and more attention. [0003] At present, research on wheel-legged robots is mainly focused on small wheel-legged robot platforms. The robot body and load capacity are small, and the combination of motor and reducer can be used to drive the leg joints; for medium / large wheel-legged robots The drive of the leg joints is driven by a servo valve control cylinder. The servo valve is installed on the hydraulic cylinder, and the piston rod of the hydraulic cylinder...

AI Technical Summary

Problems solved by technology

[0005] 1. In the hydraulic system using the servo valve control cylinder as the joint actuator of the wheel-leg robot, a centralized pump station is used as the power source. In order to maintain a constant system pressure, the pump station part needs to use an overflow valve for overflow to maintain a constant pressure. , in this way, there is always overflow loss in the pump station part, which brings about the power loss of the system

[0006] 2. The servo valve control cylinder achieves precise output force / speed control of the hydraulic cylinder through the throttling of the servo valve. There is a large throttling power loss, the transmission efficiency of the hydraulic system is low, and the effective energy utilization rate of the robot is low.

Generally, when the wheel-legged robot is running, the output torque of its joint drive device needs to overcome its own gravity and inertial force, so a larger torque is required at this time, and a hydraulic actuator is required to drive it, which can achieve a higher power density. However, when the wheel-legged robot is performing a gait to cross obstacles, the joint drive device only needs to overcome the weight of the legs at this time, so the output torque of the joint drive device required at this time is relatively small. If the servo valve is used to control For the cylinder actuator, a huge pressure difference will be generated at the valve port of the servo valve, resulting in a large throttling loss

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