Search

CN-122009359-A - Foot driving structure for humanoid robot and pitching motion method

CN122009359ACN 122009359 ACN122009359 ACN 122009359ACN-122009359-A

Abstract

The invention discloses a foot driving structure for a humanoid robot and a pitching motion method, which belong to the field of humanoid robots and comprise soles and a support frame fixed at the top end of the soles, wherein the two sides of the support frame are fixedly provided with a main body of a first motor and a main body of a second motor in an up-down staggered manner, a first connecting line between the central point of the main body of the first motor and the central point of the main body of the second motor is intersected with a second connecting line between the central point of an output shaft of the first motor and the central point of the output shaft of the second motor to form an intersection point, the intersection point is positioned on the central line at the rear side of the support frame, and the output axes of the first motor and the second motor are in non-parallel symmetrical layout, so that moment applied to the support frame during double-motor driving is symmetrically balanced on a horizontal plane. By adopting the foot driving structure and the pitching motion method for the humanoid robot, the cooperative promotion of mechanical property, transmission reliability and light weight is realized through the geometric optimization layout of the space of the double motors, the design of the integrated radial anti-loose cover plate and the directional light weight groove structure.

Inventors

  • JIANG ZHEYUAN
  • WU DONG
  • YAN DONGDONG

Assignees

  • 北京松延动力科技集团股份有限公司

Dates

Publication Date
20260512
Application Date
20260205

Claims (10)

  1. 1. The foot driving structure for the humanoid robot comprises a sole and a supporting frame fixed at the top end of the sole and is characterized in that main bodies of a first motor and a second motor are fixed at the two sides of the supporting frame in an up-down staggered mode, output shafts of the first motor and the second motor penetrate through the supporting frame and are respectively and rotatably connected with the top end of a first connecting rod and the top end of a second connecting rod through a flange plate, the bottom ends of the first connecting rod and the second connecting rod are respectively and rotatably connected with the sole, the first connecting rod and the first motor are respectively arranged at the two sides of the supporting frame, and the second connecting rod and the second motor are respectively arranged at the two sides of the supporting frame; A first connecting line between the main body center point of the first motor and the main body center point of the second motor is intersected with a second connecting line between the output shaft center point of the first motor and the output shaft center point of the second motor to form an intersection point, and the intersection point is positioned on the center line at the rear side of the support frame; The output axes of the first motor and the second motor are in non-parallel symmetrical layout, so that the moment of couple applied to the support frame during double-motor driving is symmetrically balanced on the horizontal plane.
  2. 2. The foot driving structure for a humanoid robot according to claim 1, wherein the center point of the output shaft of the first motor and the center point of the main body of the second motor form a driving center line, the driving center line is parallel to a side view center line on the sole, and a distance is left between the driving center line and the side view center line.
  3. 3. The foot driving structure for a humanoid robot according to claim 2, wherein a ratio of a distance between a driving center line and a side view center line to a side view width of a sole is 1:10 to 3:10.
  4. 4. The foot driving structure for a humanoid robot according to claim 1, wherein the second motor is located obliquely below the first motor, and the length of the second link is smaller than that of the first link.
  5. 5. The foot driving structure for the humanoid robot is characterized in that one side of the flange plate, which is far away from the supporting frame, is also covered with a radial anti-loosening component, the radial anti-loosening component is of a fan-like plate structure, the edge of the fan-like plate structure is fixedly connected with the main body of the first motor or the second motor, the fan-like plate structure protrudes outwards to form a positioning plate corresponding to the position of the output shaft of the first motor or the second motor, and the positioning plate is movably connected with the shaft neck of the output shaft or the flange plate.
  6. 6. The foot driving structure for a humanoid robot according to claim 5, wherein the positioning plate is in clearance fit or running fit with the output shaft; Or the locating plate is in clearance fit or running fit with the shaft neck of the flange plate.
  7. 7. The foot driving structure for a humanoid robot according to claim 5, wherein the total area of the disk surface of the flange plate covered by the fan-like plate-like structure is 30% -60%.
  8. 8. The foot driving structure for a humanoid robot according to claim 7, wherein the coverage area of the sector-like plate-like structure At least one of the following conditions is satisfied: condition 1: ; Condition 2: ; In the formula, Representing the total area of the end face of the output shaft; Representing the total area of the disk surface of the flange.
  9. 9. The foot driving structure for the humanoid robot of claim 1, wherein a plurality of strip-shaped weight-reducing grooves which extend downwards and are arranged at intervals in a matrix are formed on the support frame below the first motor and the support frame below the second motor.
  10. 10. The method for pitching of the foot-operated structure for a humanoid robot as claimed in any one of claims 1 to 9, comprising the steps of: S1, receiving a target pitch angle of sole An instruction; S2, instruction calculation is carried out according to the target pitch angle Based on the kinematic model of the leg structure, the target differential angle of the first motor and the second motor for driving the sole is obtained by calculation ; S21, according to the target pitch angle And a predetermined kinematic relationship function for calculating a target differential angle : ; In the formula, Representing the distance from the sole center of rotation to the connecting rod-sole connection point; And The lengths of the first connecting rod and the second connecting rod are respectively represented; Representing the offset correction factor; representing the offset distance between the driving center line and the sole-side vision weight center line; Representing the lateral width of the sole; S22, according to the target differential angle And the middle position reference angle of sole Respectively calculating first target rotation angles of the first motor Second target rotation angle with second motor : ; ; S3, controlling the first motor to rotate to a first target rotation angle Simultaneously controlling the second motor to rotate to a second target rotation angle Differential rotation of the double motors is realized, and the first connecting rod and the second connecting rod at two sides are respectively driven by the corresponding flange plates to generate differential displacement, so that the sole generates a pitch angle with a target around the central axis or a mechanical balance rotation point Corresponding pitching motion.

Description

Foot driving structure for humanoid robot and pitching motion method Technical Field The invention relates to the technical field of humanoid robots, in particular to a foot driving structure for a humanoid robot and a pitching motion method. Background The humanoid robot is used as a point direction and core research hot spot in the robot field, the performance of a lower limb movement system directly determines whether the robot can realize humanized flexible movement, and a foot driving device is used as an execution tail end of lower limb movement, so that the key point of affecting the walking stability, the terrain adaptability and the energy efficiency of the robot is more important. The foot needs to simulate the motion characteristics of human soles and has the motion capability of multiple degrees of freedom, wherein the front-back pitching of the soles relative to ankle joints can ensure the adaptation to the height drop of the ground during walking, the left-right lateral swaying can realize the posture correction of uneven ground, and the two form the basis of the human-like flexible gait. To achieve this dual degree of freedom motion, a technical path integrating multiple drive units (e.g. servo motors) at the foot or ankle joint is commonly adopted in the industry, wherein dual motor drive is a mainstream typical solution because of relatively compact structure and clear control logic. At present, the core structure of the double-motor driving scheme is designed in such a way that two driving motors are arranged on the sole or a connecting piece thereof side by side, and the motion of the sole in the pitching and side swinging directions is respectively controlled through transmission parts such as a connecting rod and the like. However, in practical applications, to meet the requirements of device compactness and high performance, three major technical challenges are faced, as follows: 1. The inherent contradiction between the space layout and the mechanical property is that in order to adapt to the limited installation space of the foot of the humanoid robot, the two motors in the existing design usually adopt a close side-by-side layout mode, so that the output axes of the two motors are parallel and have a relatively close interval. The simple parallel layout has the obvious mechanical defects that when the sole is driven to perform the compound motion of pitching and side swinging, transmission paths of driving moment are in asymmetric distribution, the force arm distribution is unbalanced, and asymmetric torsional stress is generated at the motor installation part and the connection node of the support frame. Meanwhile, the overall gravity center of the motor group and the stress center of the sole are not optimally matched in a side-by-side layout, so that eccentric load is required to be additionally overcome in the driving process, the driving load of the motor is increased, the dynamic response sensitivity of gait adjustment is reduced, and energy waste is caused. 2. The reliability of the transmission connection is insufficient, namely the connection between the output end of the motor and the connecting rod is a key link of power transmission, and the connection between the motor and the connecting rod is realized by adopting a key connection, a fastener connection (such as bolt fixing) or a direct sleeving manner in the prior art. However, under the complex working conditions of dynamic walking, obstacle crossing, ground impact, rapid posture adjustment and the like of the robot, the joint is required to bear complex radial and axial alternating loads with large instantaneous impact force and changeable directions. The traditional connection mode can only realize circumferential torque transmission or simple axial fixation, lacks an effective radial displacement constraint structure-key connection does not have a radial limiting function, a fastener is easy to loosen due to vibration, a gap exists to cause radial play when the fastener is directly sleeved, the defects enable the connecting rod and the motor output end to have risks of loosening, shaking and even connection failure, the stability and the safety of the overall operation of the robot are directly threatened, and gait runaway can be caused when the situation is serious. 3. The weight of the foot driving device as a moving end part directly affects the overall energy consumption and the lower limb joint load of the robot, namely, the foot inertial load can be amplified along with the joint movement, so that the energy consumption of a lower limb driving unit is increased, and the joint abrasion is increased. Therefore, lightweight designs are an important design goal for foot drives, and it is common practice in the industry to provide weight-reducing holes or grooves in the support structure to reduce weight. However, the existing weight reducing design lacks systematic mechanical analysis, and often has the problems