公开(公告)号：US12145277B2

公开(公告)日：2024-11-19

申请号：US17011428

申请日：2020-09-03

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Tetsuaki Kato

IPC: B25J9/16 ,  B25J19/02

Abstract: A robot motion planning technique using an external computer communicating with a robot controller. A camera or sensor system provides input scene information including start and goal points and obstacle data to the computer. The computer plans a robot tool motion based on the start and goal points and the obstacle environment, where the robot motion is planned using either a serial or parallel combination of sampling-based and optimization-based planning algorithms. In the serial combination, the sampling method first finds a feasible path, and the optimization method then improves the path quality. In the parallel combination, both sampling and optimization methods are used, and a path is selected based on computation time, path quality and other factors. The computer converts dense planned waypoints to sparse command points for transfer to the robot controller, and the controller computes robot kinematics and interpolation points and controls the movement of the robot.

公开(公告)号：US12122052B2

公开(公告)日：2024-10-22

申请号：US17654929

申请日：2022-03-15

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Tetsuaki Kato

IPC: B25J9/16 ,  G05B19/4061

CPC classification number: B25J9/1666 ,  B25J9/1607 ,  G05B19/4061 ,  G05B2219/39082 ,  G05B2219/40327

Abstract: A robot interference checking motion planning technique using swept volume deformation. A rapidly-exploring random tree (RRT) algorithm generates random sample nodes between a start point and a goal point. Each sample node is evaluated by checking for robot-obstacle interference along a path segment to the node. If an interference exists along the path segment, a swept volume of the segment is used to identify a critical posture where the interference is greatest, and obstacle interference points are used to define a virtual force applied to the robot links to modify the path segment to alleviate the interference condition. A swept volume of the modified path segment is computed and evaluated. If the modified swept volume is collision-free and the modified path segment motion plan meets robot joint range criteria, the modified path segment and the sample node are added to the overall robot motion program.

公开(公告)号：US20240190002A1

公开(公告)日：2024-06-13

申请号：US18588084

申请日：2024-02-27

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Yongxiang Fan ,  Tetsuaki Kato

IPC: B25J9/16 ,  G06F30/10

CPC classification number: B25J9/1664 ,  B25J9/1605 ,  G06F30/10

Abstract: An object interference checking technique using point sets which uses CAD models of objects and obstacles and converts the CAD models to 3D points. The 3D point locations are updated based on object motion. The 3D points are then converted to 3D grid space indices defining space occupied by any point on any object or obstacle. The 3D grid space indices are then converted to 1D indices and the 1D indices are stored as a set per object and per position. Swept volumes for an object are created by computing a union of the 1D index sets across multiple motion steps. Interference checking between objects is performed by computing an intersection of the 1D index sets for a given motion step or position. The 1D indices are converted back to 3D coordinates to define the 3D shapes of the swept volumes and interferences.

公开(公告)号：US11872704B2

公开(公告)日：2024-01-16

申请号：US17455676

申请日：2021-11-19

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Chiara Talignani Landi ,  Chi-Keng Tsai ,  Tetsuaki Kato

IPC: B25J13/08 ,  B25J9/16

CPC classification number: B25J9/1666 ,  B25J9/1651 ,  B25J9/1653 ,  B25J9/1676 ,  B25J9/1697 ,  B25J13/089

Abstract: A method and system for dynamic collision avoidance motion planning for industrial robots. An obstacle avoidance motion optimization routine receives a planned path and obstacle detection data as inputs, and computes a commanded robot path which avoids any detected obstacles. Robot joint motions to follow the tool center point path are used by a robot controller to command robot motion. The planning and optimization calculations are performed in a feedback loop which is decoupled from the controller feedback loop which computes robot commands based on actual robot position. The two feedback loops perform planning, command and control calculations in real time, including responding to dynamic obstacles which may be present in the robot workspace. The optimization calculations include a safety function which efficiently incorporates both relative position and relative velocity of the obstacles with respect to the robot.

公开(公告)号：US20250128377A1

公开(公告)日：2025-04-24

申请号：US18491107

申请日：2023-10-20

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Tetsuaki Kato

IPC: B23Q15/12

Abstract: A method for machine tool motion control which determines a time-optimal trajectory for a multi-segment tool path motion. Start and end waypoints for each segment of the overall motion are defined, along with other conditions such as cutting feed speed. An initial motion profile for each segment is computed based on the waypoint geometry and other constraints, and motion states at the waypoints which join the segments are optimized to provide the shortest total trajectory time. The optimized waypoint states include velocities and accelerations with non-zero values. An extra waypoint may be added to the trajectory, such as for collision avoidance, and the waypoint states are again optimized for minimum total time of the complete trajectory. Heuristic and gradient descent techniques are applied for computation of the optimum waypoint state values.

公开(公告)号：US20240116178A1

公开(公告)日：2024-04-11

申请号：US17935293

申请日：2022-09-26

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Yu Zhao ,  Tetsuaki Kato

IPC: B25J9/16

CPC classification number: B25J9/1633 ,  B25J9/163 ,  B25J9/1638 ,  B25J9/1641 ,  B25J9/1651 ,  B25J9/1664

Abstract: A method and system for robot motion control using a model predictive control (MPC) technique including torque rate control and suppression of end tooling oscillation. An MPC module includes a robot dynamics model which inherently reflects response nonlinearities associated with changes in robot configuration, and an optimization solver having an objective function with a torque rate term and inequality constraints defining bounds on both torque and torque rate. The torque rate control in the MPC module provides an effective means of controlling jerk in robot joints, while accurately modeling robot dynamics as the robot changes configuration during a motion program. End tooling oscillation dynamics may also be included in the MPC objective function and constraints in order to automatically control end tooling vibration in the calculations of the MPC module.

公开(公告)号：US20230182299A1

公开(公告)日：2023-06-15

申请号：US17644123

申请日：2021-12-14

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Tetsuaki Kato ,  Chi-Keng Tsai

IPC: B25J9/16 ,  B25J9/00

CPC classification number: B25J9/1666 ,  B25J9/0087

Abstract: A deadlock avoidance motion planning technique for a multi-robot system. The technique includes online calculation of swept volumes for upcoming robot motion segments, and uses the swept volumes to compute one or more overlap zones, which are published to all robot controllers. Swept volume calculation is based on actual upcoming tool path, including adaptive conditions such as jumps and offsets. Robot controllers check at each time step whether an overlap zone will be entered and whether another robot is already in the zone. When a robot determines that it is about to enter a zone that is occupied, the robot holds position until the zone is vacated. Robots publish zone entry and exit for other robots’ awareness. Additional logic is added to establish priority for automatically resolving a deadlock condition, and for prioritizing completion of motion segments for a robot which is performing a continuous processing operation.

公开(公告)号：US20210308862A1

公开(公告)日：2021-10-07

申请号：US16839642

申请日：2020-04-03

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Tetsuaki Kato

IPC: B25J9/16

Abstract: A robot collision avoidance motion optimization technique using a distance field constraint function. CAD or sensor data depicting obstacles in a robot workspace are converted to voxels, and a three-dimensional binary matrix of voxel occupancy is created. A corresponding distance map matrix is then computed, where each cell in the distance map matrix contains a distance to a nearest occupied cell. The distance map matrix is used as a constraint function in a motion planning optimization problem, where the optimization problem is convexified and then iteratively solved to yield a robot motion profile which avoids the obstacles and minimizes an objective function such as distance traveled. The distance field optimization technique is quickly computed and has a computation time which is independent of the number of obstacles. The disclosed optimization technique is easy to set up, as it requires no creation of geometry primitives to approximate robot and obstacle shapes.

公开(公告)号：US20250130548A1

公开(公告)日：2025-04-24

申请号：US18604641

申请日：2024-03-14

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Zheng Tong ,  Tetsuaki Kato

IPC: G05B19/402 ,  B23Q15/12

Abstract: A method for machine tool motion control which determines a time-optimal motion plan for a hole tapping step preceded by an air cut step. The motion plan for the air cut step is computed so that the tapping tool arrives at the top of the hole to be tapped with the proper axial tapping feed speed and the proper tapping rotational velocity. First, time durations for the air cut step are computed for lateral and axial transit motions and for spindle acceleration under maximum-effort conditions. The longest of the time durations is then used to plan the air cut step, where the time-limiting axis motion is performed at maximum machine effort, and other axes have their motions planned to complete at the same time as the longest-duration axis. The technique is applicable to an air cut step before a tapping step or in between two tapping steps.

公开(公告)号：US20250130547A1

公开(公告)日：2025-04-24

申请号：US18491147

申请日：2023-10-20

Applicant: FANUC CORPORATION

Inventor： Hsien-Chung Lin ,  Tetsuaki Kato

IPC: G05B19/19 ,  B23Q15/12

Abstract: A method for programming a multi-segment motion plan for a machine tool which uses program points defined directly on a workpiece surface, and computes a time-optimal trajectory which transitions from air cut to cutting without stopping, while arriving at a cutting start waypoint traveling at a specified cutting feed speed. The programming method also combines what are traditionally separate air cut and cutting commands into a single command, and computes the time-optimal trajectory for all segments. The underlying time-optimal trajectory computation calculates an initial motion profile for each segment based on the waypoint geometry and other constraints, and motion states at the waypoints which join the segments are optimized to provide the shortest total trajectory time. The optimized waypoint states include velocities and accelerations with non-zero values.