Search

CN-121649959-B - Foldable seven-degree-of-freedom hybrid robot

CN121649959BCN 121649959 BCN121649959 BCN 121649959BCN-121649959-B

Abstract

The invention discloses a foldable seven-degree-of-freedom hybrid robot, and belongs to the technical field of multi-degree-of-freedom hybrid robots. The robot comprises a base, a parallel part and a serial four-degree-of-freedom mechanical arm. The parallel connection part comprises an UP branched chain serving as a main support and two UCU branched chains serving as auxiliary supports, one ends of the UP branched chains and the UCU branched chains are fixed on the base, and the other ends of the UCU branched chains are fixedly connected with the serial mechanical arm. The UP branched chain and the two UCU branched chains respectively comprise a drive, so that the parallel connection part has three degrees of freedom. The serial mechanical arm provides four degrees of freedom, and forms a seven-degree-of-freedom system together with the parallel part, so that the end effector has full-dimension motion capability and contains one redundant degree of freedom for smart operation. The invention adopts serial-parallel connection configuration, has high rigidity and high precision of a large working space of a serial mechanism and a parallel mechanism, has a foldable integral structure, and greatly improves the space utilization rate in a non-working state.

Inventors

  • HE JUN
  • YUAN ZHICHENG

Assignees

  • 上海交通大学

Dates

Publication Date
20260512
Application Date
20260116

Claims (7)

  1. 1. A foldable seven-degree-of-freedom hybrid robot, comprising: the base is used as a mounting base of the series-parallel robot; The parallel connection part comprises a main support branched chain and two auxiliary support branched chains with the same structure, wherein one end of the main support branched chain and one end of each auxiliary support branched chain are fixedly connected with the base through respective universal joint static frames, the other end of the main support branched chain and the other end of each auxiliary support branched chain are fixedly connected with the parallel connection tail end of the parallel connection part, the main support branched chain and the two auxiliary support branched chains respectively comprise a driving device, so that the parallel connection part has three degrees of freedom, and the axes of the universal joint static frames corresponding to the main support branched chain and the two auxiliary support branched chains are mutually parallel, so that the parallel connection part has a completely resolved form of kinematic positive solution; The four-degree-of-freedom mechanical arm is connected in series, the base of the four-degree-of-freedom mechanical arm is fixedly connected with the parallel tail end of the parallel part, and the axis of the base of the four-degree-of-freedom mechanical arm is parallel to the axis of the universal joint static frame of the parallel tail end; the seven-degree-of-freedom robot jointly contributed by the parallel part and the serial part has a completely resolved kinematic positive solution, and the whole robot is foldable in a non-working state; The main supporting branched chain is an UP kinematic chain and comprises a first universal joint and a first reversing planetary roller screw rod, wherein the base frame of the first universal joint is fixed on a base, the output of the first universal joint is fixedly connected with the shell of the first reversing planetary roller screw rod, and the output end of the first reversing planetary roller screw rod is fixedly connected with the parallel tail end; The two auxiliary supporting branched chains of the parallel part are UCU branched chains, each UCU branched chain comprises a second base universal joint serving as a U pair, a second reverse planetary roller screw, a second free rotary bearing, a second free moving rotary shaft and a second tail end universal joint serving as another U pair, the second reverse planetary roller screw, the second free rotary bearing and the second free moving rotary shaft jointly form a C pair, the base frame of the second base universal joint is fixed on a base, the output of the second base universal joint is fixedly connected with the shell of the second reverse planetary roller screw, the output end of the second reverse planetary roller screw is fixedly connected with the input of the second free rotary bearing, the output of the second free rotary bearing is fixedly connected with the second free moving rotary shaft, the second free moving rotary shaft is connected with the base of the second tail end universal joint, and the output of the second tail end universal joint is connected with the tail end of the parallel part; The second end universal joint comprises a second end universal joint static frame, a second end universal joint fixed shaft rotating piece and a second end universal joint movable shaft rotating piece, the second end universal joint static frame is a part of parallel connection ends, the second end universal joint fixed shaft rotating piece can rotate around the second end universal joint static frame, the second end universal joint movable shaft rotating piece can rotate around the second end universal joint fixed shaft rotating piece, the second end universal joint movable shaft rotating piece is fixedly connected with a second lead screw, and the second end universal joint fixed shaft rotating piece and the second end universal joint movable shaft rotating piece are vertically distributed.
  2. 2. The foldable seven-degree-of-freedom hybrid robot of claim 1 wherein the first gimbal includes a first gimbal mount, a first gimbal fixed axis rotation, a first gimbal movable axis rotation, the first gimbal mount being secured to the base, the first gimbal fixed axis rotation being rotatable about the first gimbal mount, the first gimbal movable axis rotation being rotatable about the first gimbal fixed axis rotation, the first gimbal movable axis rotation being secured to the housing of the first reversing planetary roller screw, the first gimbal fixed axis rotation being vertically distributed with the first gimbal movable axis rotation.
  3. 3. The foldable seven-degree-of-freedom hybrid robot of claim 2, wherein the first reversing planetary roller screw comprises a housing of the first reversing planetary roller screw, a first nut housing, a first roller retainer, a plurality of first rollers, the first screw, the housing of the first reversing planetary roller screw is fixedly connected with a housing of a frameless motor, the first nut housing is fixedly connected with a rotor of the frameless motor, the first roller retainer is fixedly connected with the first screw, the first nut housing is meshed with threads of the plurality of first rollers, the first rollers are mounted on the first roller retainer, the plurality of first rollers are in planetary distribution, the gears of the first rollers are meshed with the threads of the first screw, the first nut housing is driven to rotate by the motor, the first rollers on the first roller retainer are driven by the first nut housing to start planetary motion, and the first rollers are driven by the first roller to perform linear motion.
  4. 4. The foldable seven-degree-of-freedom hybrid robot of claim 1 wherein the second base gimbal includes a second base gimbal mount, a second base gimbal fixed axis rotation, a second base gimbal movable axis rotation, the second base gimbal mount being secured to the base, the second base gimbal fixed axis rotation being rotatable about the second base gimbal mount, the second base gimbal movable axis rotation being rotatable about the second base gimbal fixed axis rotation, the second base gimbal movable axis rotation being secured to the housing of the second reversing planetary roller screw, the second base gimbal fixed axis rotation being vertically distributed with the second base gimbal movable axis rotation.
  5. 5. The foldable seven-degree-of-freedom hybrid robot of claim 1, wherein the second reversing planetary roller screw comprises a housing of the second reversing planetary roller screw, a second nut housing, a second roller retainer, a plurality of second rollers, and a second screw, wherein the housing of the second reversing planetary roller screw is fixedly connected with a housing of a frameless motor, the second nut housing is fixedly connected with a rotor of the frameless motor, the second roller retainer is fixedly connected with the second screw, the second nut housing is meshed with threads of the plurality of second rollers, the second rollers are mounted on the second roller retainer, the plurality of second rollers are in planetary distribution, the gears of the second rollers are meshed with the threads of the second screw, the second nut housing is driven to rotate by the motor, the second rollers on the second roller retainer are driven by the second nut housing to start planetary motion, and the second rollers are driven by the second roller retainer to perform linear motion.
  6. 6. The foldable seven-degree-of-freedom hybrid robot of claim 1, wherein the serial four-degree-of-freedom mechanical arm comprises a serial base and serial first drive, a serial first connecting rod and serial second drive, a serial second connecting rod and serial third drive, a serial third connecting rod and serial fourth drive, and a serial fourth connecting rod, wherein the serial base and serial first drive are fixedly connected with the parallel tail end, a serial first connecting rod and serial second drive rotor are fixedly connected with the serial first connecting rod and serial second drive stator, a serial first connecting rod and serial second drive rotor are fixedly connected with the serial second connecting rod and serial third drive stator, a serial second connecting rod and serial third drive rotor are fixedly connected with the serial third connecting rod and serial fourth drive stator, and a serial third connecting rod and serial fourth drive rotor are fixedly connected with the serial fourth connecting rod.
  7. 7. The foldable seven-degree-of-freedom hybrid robot of claim 6, wherein the axes of the series base and the series first drive are parallel to the parallel portion second end gimbal rest axis, the axes of the series first link and the series second drive are perpendicular to the axes of the series base and the series first drive, the axes of the series second link and the series third drive are perpendicular to the axes of the series first link and the series second drive, the axes of the series third link and the series fourth drive are perpendicular to the axes of the series second link and the series third drive, and the axes of the series first link and the series second link and the series third drive, and the axes of the series third link and the series fourth drive intersect at a point in any posture of the series portion.

Description

Foldable seven-degree-of-freedom hybrid robot Technical Field The invention belongs to the technical field of multi-degree-of-freedom hybrid robots, and particularly relates to a foldable seven-degree-of-freedom hybrid robot. Background When complex tasks such as space station construction and assembly, non-cooperative target capture, planetary surface detection, equipment maintenance and repair and the like are performed, dangerous or highly difficult operating environments are often faced, so that manual direct operation is extremely difficult. Robotics, because of their high precision, versatility and efficiency, exhibit great potential for application in these fields. At present, robots widely used in industrial fields mainly include serial mechanical arms, and generally have 6 or 7 degrees of freedom. The serial mechanical arm has the advantages of large working space and flexible movement, but the rigidity of the serial mechanical arm is generally low, so that the end effector is easy to generate large vibration when being far away from the base, and the stability of the system is affected. Meanwhile, as joint errors can be accumulated step by step, the positioning precision of the tail ends of the serial mechanical arms is relatively limited, and the performance is obviously reduced when a large load is borne. The parallel robot has the advantages of high rigidity, high precision and strong bearing capacity, but the working space is usually smaller, the movement flexibility is insufficient, and the parallel robot is difficult to adapt to complex and changeable task demands. In the prior art, researches disclose a mechanical arm with a lockable telescopic arm rod, wherein the flexibility is improved through the telescopic arm rod, but the problem of terminal precision is not fundamentally solved, and an eight-degree-of-freedom redundant system of the mechanical arm leads to complex inverse kinematics solution and large control difficulty. Other foldable or telescopic mechanical arm designs are also focused on space storage, and work space or movement flexibility is often sacrificed while rigidity and precision are improved. In summary, the existing robot technology has the defects that the end precision and the system rigidity are difficult to be compatible, the bearing capacity is limited, the robot with excessive degrees of freedom has the problems of complex kinematics solution and difficult control, the mechanical arm is huge in size, occupies a large amount of space when not working, and is inconvenient to store. Therefore, there is an urgent need for a robot solution that combines high precision, high rigidity, large working space, strong carrying capacity and efficient stowability. Disclosure of Invention In order to solve the technical problems, the invention provides a foldable seven-degree-of-freedom hybrid robot which can improve the overall rigidity, the end precision and the system stability, so that the robot has complete analysis and forward decomposition and has foldable capability in a non-working state. In order to achieve the above purpose, the invention adopts the following technical scheme: a foldable seven-degree-of-freedom hybrid robot, comprising: the base is used as a mounting base of the series-parallel robot; The parallel connection part comprises a main support branched chain and two auxiliary support branched chains with the same structure, wherein one end of the main support branched chain and one end of each auxiliary support branched chain are fixedly connected with the base through respective universal joint static frames, the other end of the main support branched chain and the other end of each auxiliary support branched chain are fixedly connected with the parallel connection tail end of the parallel connection part, the main support branched chain and the two auxiliary support branched chains respectively comprise a driving device, so that the parallel connection part has three degrees of freedom, and the axes of the universal joint static frames corresponding to the main support branched chain and the two auxiliary support branched chains are mutually parallel, so that the parallel connection part has a completely resolved form of kinematic positive solution; The four-degree-of-freedom mechanical arm is connected in series, the base of the four-degree-of-freedom mechanical arm is fixedly connected with the parallel tail end of the parallel part, and the axis of the base of the four-degree-of-freedom mechanical arm is parallel to the axis of the universal joint static frame of the parallel tail end; the seven-degree-of-freedom robot jointly contributed by the parallel part and the serial part has a completely resolved kinematic ortholysis, and the whole robot is foldable in a non-working state. The invention has the beneficial effects that: By creatively adopting a series-parallel configuration combining a 1UP-2UCU parallel mechanism and a four-degree-of-freedom se