Apparatus and method for coaxially aligning two rotatable shafts

A method for aligning two rotatable shafts which are coaxially coupled together, the method comprising:

• providing a servo operated multi axis robotic arm attachable to a base affixed in spaced relation to axis of two axially coupled rotating shafts oriented along a X-axis, the robotic arm having a distal end pivotably attached to a laser range finder (LRF) to orient the LRF a distance from the two rotating shafts to measures the location of a plurality of peripherally spaced spots on the shafts at two spaced apart axial positions on each shaft;
• providing a controller, having a processor and memory, communicating with the servo motors of the multi axis robotic arm, the LRF and a user interface;
• positioning the LRF at a first X-axis location on a first one of the rotating shafts, causing the controller communicating the servo motors of the multi axis robotic arm, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• positioning the LRF at a second X-axis location on the first rotating shaft, axially spaced apart, from the first X-axis location, causing the controller communicating the servo motors of the multi axis robotic arm, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• positioning the LRF at a third X-axis location on a second one of the rotating shafts, causing the controller communicating the servo motors of the multi axis robotic arm, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• positioning the LRF at a fourth X-axis location on the second rotating shaft, axially spaced apart from the third X-axis location, causing the controller communicating the servo motors of the multi axis robotic arm, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• and
• calculating in the processor the centerline of the two shafts at each of the four X-axis locations using stored LRF location and the measured distance to a plurality of peripherally spaced spots, using a best-fit circle algorithm to define two spaced apart axis location points for each shaft and determining the adjustment of one of the two shafts needed to move the shafts in to coaxial alignment and outputting the adjustment information to the user via the user interface.

An apparatus for aligning two rotatable shafts which are coaxially coupled together, the apparatus comprising:

• a base which is positionable in spaced adjacent orientation to two rotatable shafts which are coaxially coupled together;
• a vertical guide supported on the base and movable relative thereto in a longitudinal direction parallel to the axis of the shafts and a transverse direction perpendicular to the shaft axis in plan view by a longitudinal servo and a transverse servo respectively;
• a laser range finder (LRF) positionable a distance from the two rotating shafts to measures the location of a plurality of vertically spaced spots on the shafts at two axial positions on each shaft, the LRF movable along the vertical guide by a vertical servo;
• a controller communicating with servo motors of the longitudinal servo, the transverse servo and the vertical servo, the controller having a processor programmed to:
• position the LRF at a first longitudinal location adjacent a first one of the rotatable shafts, causing the servo motors to move the LRF vertically relative the shaft and storing the LRF location and the measured distance to a plurality of vertically spaced spots;
• position the LRF at a second longitudinal location adjacent a first one of the rotatable shafts, causing the servo motors to move the LRF vertically relative the shaft and storing the LRF location and the measured distance to a plurality of vertically spaced spots;
• position the LRF at a third longitudinal location adjacent a second one of the rotatable shafts, causing the servo motors to move the LRF vertically relative the shaft and storing the LRF location and the measured distance to a plurality of vertically spaced spots;
• position the LRF at a fourth longitudinal location adjacent a second one of the rotatable shafts, causing the servo motors to move the LRF vertically relative the shaft and storing the LRF location and the measured distance to a plurality of vertically spaced spots;
• and
• calculate the centerline of the two shafts at each of the four longitudinal locations using stored measurement and spot location data, locating an axis for each of the two shafts, and determining an adjustment for one of the two shafts to move the shafts in to coaxial alignment.

A method for aligning two rotatable shafts which are coaxially coupled together, the method comprising:

• providing a servo operated multi axis positioning device having at least 3 degrees of freedom attachable to a base affixed in spaced relation to axis of two axially coupled rotating shafts oriented along a X-axis, the robotic arm having a distal end pivotably attached to a laser range finder (LRF) to orient the LRF a distance from the two rotating shafts to measures the location of a plurality of peripherally spaced spots on the shafts at two spaced apart axial positions on each shaft;
• providing a controller, having a processor and memory, communicating with the servo motors of the multi axis positioning device, the LRF and a user interface;
• positioning the LRF at a first X-axis location on a first one of the rotating shafts, causing the controller communicating the servo motors of the multi axis positioning device, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• positioning the LRF at a second X-axis location on the first rotating shaft, axially spaced apart, from the first X-axis location, causing the controller communicating the servo motors of the multi axis positioning device, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• positioning the LRF at a third X-axis location on a second one of the rotating shafts, causing the controller communicating the servo motors of the multi axis positioning device, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• positioning the LRF at a fourth X-axis location on the second rotating shaft, axially spaced apart from the third X-axis location, causing the controller communicating the servo motors of the multi axis positioning device, to move the LRF peripherally about the shaft and storing the LRF location and the measured distance to a plurality of peripherally spaced spots;
• and
• calculating in the processor the centerline of the two shafts at each of the four X-axis locations using stored LRF location and the measured distance to a plurality of peripherally spaced spots, using a best-fit circle algorithm to define two spaced apart axis location points for each shaft and determining the adjustment of one of the two shafts needed to move the shafts in to coaxial alignment and outputting the adjustment information to the user via the user interface.