Spherical coordinate steering mechanism

Abstract

The present invention is a spherical coordinate steering mechanism constructed with twelve-axis geometry and capable of being manipulated according to spherical coordinate motion, so that the twelve-axis torque can be integrated and output through four sets of arc rods connected in parallel and in series. In short: working together without burdening each other. This is the characteristic of a spatial parallel mechanism and the motivation for inventing a spherical coordinate steering mechanism. Assuming the total required power output is the same, compared to the series configuration in which a single high-voltage motor that increases the speed needs to pass through a reducer to further amplify the torque, the parallel configuration of multiple low-voltage motors directly amplifies the torque, actively outputs three-degree-of-freedom torque, and reduces energy loss due to mechanical loss in the reduction gear. The present invention can be applied to the operation of a composite machining center, a multi-dimensional measuring machine, or extreme sports, and can also be applied to the shoulder joint or hip joint of a robot.

Claims

1. A mechanism constructed with twelve axes and capable of motion control according to spherical coordinates, comprising: A base frame assembly, the base frame assembly comprising a base frame structure composed of a plurality of arc frames and four base frame rotation modules mounted on the base frame structure, the base frame structure having four end corners defining a base frame geometric tetrahedron, the output axes defining the four base frame rotation modules respectively coinciding with the four corner centerlines of the base frame geometric tetrahedron, and the four corner centerlines centripetally intersecting at the center point of the base frame structure, wherein the angle between the output axes of any two base frame rotation modules is greater than 75 degrees and less than 150 degrees, and each base frame rotation module comprises an outer tubular shaft and an inner tubular shaft, such that the outer tubular shaft and the inner tubular shaft of the base frame rotation module rotate coaxially, the outer tubular shaft being divided into a driving end and a driven end, and the inner tubular shaft being divided into a driving end and a driven end; Two end frame assemblies, each end frame assembly comprising an end frame structure and two end frame rotation modules mounted on the end frame structure, the end frame structure having two end corners defining an end frame geometric arc, the output axes defining the two end frame rotation modules respectively coinciding with the two angular centerlines of the end frame geometric arc, and the two angular centerlines intersecting concentrically at the center of the base frame structure so that the end frame assembly circular track rotates about the center point, wherein the angle between the two output axes of the end frame rotation modules of each end frame assembly is greater than 75 degrees and less than 150 degrees; Four groups of arc rod groups, each group of arc rod groups includes a base arc rod, an end arc rod, an arc rod rotation module, a base pulley, an end pulley, a timing belt, and at least one pair of synchronous idler pulleys; the base arc rod can be divided into a base end and an end end, and the end arc rod can be divided into a base end and an end end, the end end of the base arc rod and the base end of the end arc rod rotate coaxially through the arc rod rotation module, so that the base end of the base arc rod is coaxially locked to the inner tube shaft driving end of the base frame rotation module; the end end of the end arc rod rotates coaxially with an end frame rotation module, the end end of the end arc rod rotates coaxially with an end frame rotation module, and the output axis of the arc rod rotation module normally points to the center point of the base frame, so that the arc rod group ring track rotates around the center point between the base frame structure and the two end frame structures, wherein the angle between the output axes of any two base frame rotation modules is less than or equal to the sum of the arc lengths of the two corresponding base arc rods, wherein the angle between the output axes of the two end frame rotation modules of any end frame is less than or equal to the sum of the arc lengths of the two corresponding terminal arc rods; the base pulley is coaxially locked to the inner tube shaft driving end of the base frame rotation module; the terminal pulley is coaxially locked to the base end of the terminal arc rod, and the terminal pulley is coaxially connected to the arc rod rotation module; the at least one pair of synchronous idler pulleys are respectively borne on the two sides of the rod of the base arc rod, and the wheel edge of the at least one pair of synchronous idler pulleys does not exceed the outer edge of the rod arc of the base arc rod; one end of the timing belt is meshed and rotated with the base pulley, and the other end of the timing belt is meshed and rotated with the terminal pulley, and the direction and tension of the timing belt are adjusted by the at least one pair of synchronous idler pulleys; so that the base pulley drives the terminal pulley through the timing belt; At least one base connection drive group includes a base connection drive module, a base connection drive gear, and a base connection driven gear; the base connection drive gear is locked to the output shaft end of the base connection drive module; the base connection driven gear is coaxially locked to the driven end of the outer tube shaft of the base frame rotation module; the axial center distance between the base connection drive gear and the base connection driven gear is the sum of the base radius of the two gears, and the base connection drive gear and the base connection driven gear are engaged with each other, so that the base connection drive module rotates the base connection driven gear synchronously through the base connection drive gear; At least one end-connection drive group comprises an end-connection drive module, an end-connection drive gear and an end-connection driven gear; the end-connection drive gear is locked to the output shaft end of the end-connection drive module, and the end-connection driven gear is coaxially locked to the driven end of the inner tube shaft of the base frame rotation module; the axial center distance between the end-connection drive gear and the end-connection driven gear is the sum of the base radii of the two gears, and the end-connection drive gear and the end-connection driven gear are meshed with each other, so that the end-connection drive module can synchronously rotate the end-connection driven gear through the end-connection drive gear; and At most two crank groups, each crank group includes an arc crank and a crank rotation module, one end of the arc crank is fixed with an extension rod extending centripetally relative to the opposite side of the base frame structure, the other end of the arc crank and the base arc rod are coaxially mounted on a base frame rotation module so that the arc crank can rotate around the same center point in a circular orbit, the crank rotation module is coaxially mounted on the base frame rotation module, and the crank rotation module can drive the arc crank in a timely manner to avoid possible interference between the base frame structure and any base arc rod, wherein the arc length of the arc crank is less than or equal to 90 degrees.

2. The mechanism as claimed in claim 1, wherein the axial center distance between the base drive gear and the base driven gear of each base drive group is zero, so that the base drive module is coaxially locked to the driven end of the outer tube shaft of the base frame rotation module.

3. The mechanism as claimed in claim 1, wherein the axial center distance between the terminal drive gear and the terminal driven gear of each terminal drive group is zero, so that the terminal drive module is coaxially locked to the driven end of the inner tube shaft of the base frame rotation module.

4. The mechanism as claimed in claim 1, wherein each end frame assembly can be provided with an end frame bearing seat on the opposite end side of the end frame structure to the end arc rod to mount a payload.

5. The mechanism as claimed in claim 1, wherein each crank assembly can be provided with a crank bearing seat at the end of the extension rod of the arc crank opposite to the base frame structure to mount a payload.

6. The mechanism of claim 1 , wherein the base frame rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three; the end frame rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three; the arc rod rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three; and the crank rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three.

7. The mechanism as claimed in claim 1, wherein the base frame structure of the base frame assembly can be a closed design to enhance rigidity to prevent vibration or deformation, or an open-loop design to avoid possible interference with the operation of the arc rod assembly or the crank assembly.

8. A mechanism constructed with twelve axes and capable of motion control according to spherical coordinates, comprising: A base frame assembly, the base frame assembly comprising a base frame structure composed of a plurality of arc frames and four base frame rotation modules mounted on the base frame structure, the base frame structure having four end corners defining a base frame geometric tetrahedron, the output axes defining the four base frame rotation modules respectively coinciding with the four corner centerlines of the base frame geometric tetrahedron, and the four corner centerlines centripetally intersecting at the center point of the base frame structure, wherein the angle between the output axes of any two base frame rotation modules is greater than 75 degrees and less than 150 degrees, and each base frame rotation module comprises an outer tubular shaft and an inner tubular shaft, such that the outer tubular shaft and the inner tubular shaft of the base frame rotation module rotate coaxially, the outer tubular shaft being divided into a driving end and a driven end, and the inner tubular shaft being divided into a driving end and a driven end; Two end frame assemblies, each end frame assembly comprising an end frame structure and two end frame rotation modules mounted on the end frame structure, the end frame structure having two end corners defining an end frame geometric arc, the output axes defining the two end frame rotation modules respectively coinciding with the two angular centerlines of the end frame geometric arc, and the two angular centerlines intersecting concentrically at the center of the base frame structure so that the end frame assembly circular track rotates about the center point, wherein the angle between the two output axes of the end frame rotation modules of each end frame assembly is greater than 75 degrees and less than 150 degrees; Four groups of arc rod groups, each group of arc rod groups includes a base arc rod, an end arc rod, an arc rod rotation module, a base pulley, an end pulley, a timing belt, and at least one pair of synchronous idler pulleys; the base arc rod can be divided into a base end and an end end, and the end arc rod can be divided into a base end and an end end, the end end of the base arc rod and the base end of the end arc rod rotate coaxially through the arc rod rotation module, so that the base end of the base arc rod is coaxially locked to the inner tube shaft driving end of the base frame rotation module; the end end of the end arc rod rotates coaxially with an end frame rotation module, the end end of the end arc rod rotates coaxially with an end frame rotation module, and the output axis of the arc rod rotation module normally points to the center point of the base frame, so that the arc rod group ring track rotates around the center point between the base frame structure and the two end frame structures, wherein the angle between the output axes of any two base frame rotation modules is less than or equal to the sum of the arc lengths of the two corresponding base arc rods, wherein the angle between the output axes of the two end frame rotation modules of any end frame is less than or equal to the sum of the arc lengths of the two corresponding terminal arc rods; the base pulley is coaxially locked to the inner tube shaft driving end of the base frame rotation module; the terminal pulley is coaxially locked to the base end of the terminal arc rod, and the terminal pulley is coaxially connected to the arc rod rotation module; the at least one pair of synchronous idler pulleys are respectively borne on the two sides of the rod of the base arc rod, and the wheel edge of the at least one pair of synchronous idler pulleys does not exceed the outer edge of the rod arc of the base arc rod; one end of the timing belt is meshed and rotated with the base pulley, and the other end of the timing belt is meshed and rotated with the terminal pulley, and the direction and tension of the timing belt are adjusted by the at least one pair of synchronous idler pulleys; so that the base pulley drives the terminal pulley through the timing belt; At least one base connection drive group includes a base connection drive module, a base connection drive gear and a base connection driven gear; the base connection drive gear is locked to the output shaft end of the base connection drive module; the base connection driven gear is coaxially locked to the driven end of the outer tube shaft of the base frame rotation module; the axial center distance between the base connection drive gear and the base connection driven gear is the sum of the base radius of the two gears, and the base connection drive gear and the base connection driven gear are meshed with each other, so that the base connection drive module can synchronously rotate the base connection driven gear through the base connection drive gear; and At least one end-connected drive group includes an end-connected drive module, an end-connected drive gear and an end-connected driven gear; the end-connected drive gear is locked to the output shaft end of the end-connected drive module, and the end-connected driven gear is coaxially locked to the inner tube shaft driven end of the base frame rotation module; the axial center distance between the end-connected drive gear and the end-connected driven gear is the sum of the base radii of the two gears, and the end-connected drive gear and the end-connected driven gear are meshed with each other, so that the end-connected drive module can synchronously rotate the end-connected driven gear through the end-connected drive gear.

9. The mechanism of claim 8, wherein the axial center distance between the base drive gear and the base driven gear of each base drive group is zero, so that the base drive module is coaxially locked to the driven end of the outer tube shaft of the base frame rotation module.

10. The mechanism of claim 8, wherein the axial center distance between the terminal drive gear and the terminal driven gear of each terminal drive group is zero, so that the terminal drive module is coaxially locked to the driven end of the inner tube shaft of the base frame rotation module.

11. The mechanism of claim 8, wherein each end frame assembly can be further provided with an end frame bearing seat on the opposite end side of the end frame structure to the end arc rod to mount a payload.

12. The mechanism of claim 8 , wherein the base frame rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three; the end frame rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three; and the arc rod rotation module is a combination of a torque output device, an angle detector, a shaft core, and a bearing, or one of the three.

13. The mechanism as claimed in claim 8, wherein the base frame structure of the base frame assembly can be a closed design to enhance rigidity to prevent vibration or deformation, or an open-loop design to avoid possible interference with the operation of the arc rod assembly.

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