Robot program changing device

A robot program changing device that changes a program of a robot performing smooth operation in which while deceleration is being performed by a first movement command, acceleration is performed by a second movement command to smoothly shift from the first movement command to the second movement command, comprising:

• a program storage unit for storing an operational program of the robot;
• an initial storage unit for storing cycle time of the operational program as initial cycle time, storing positions of a plurality of teaching points of the operational program as a plurality of initial teaching points, and storing a teaching sequence of the plurality of initial teaching points of the operational program as an initial teaching sequence, when the operational program stored in the program storage unit is executed by simulation;
• a sequence interchanging unit for interchanging the plurality of teaching points in the teaching sequence such that sum of movement time of the robot respectively spent by the robot to move between respective two of the plurality of teaching points becomes smaller than sum of movement time when the robot is moved in line with the initial teaching sequence of the plurality of initial teaching points stored in the initial storage unit;
• an arm tip position storage unit for storing positions of an arm tip of the robot at predetermined time intervals when the after-interchanged operational program for which the teaching points have been interchanged in the teaching sequence by the sequence interchanging unit is executed by simulation;
• a calculating unit for calculating, for each initial teaching point, difference amounts between a trajectory of the robot and the initial teaching points stored in the initial storage unit, the trajectory being created on the basis of the positions, stored in the arm tip position storage unit, at the predetermined time intervals;
• a position adjusting unit for adjusting the positions of the teaching points of the after-interchanged operational program until the difference amounts calculated by the calculating unit becomes equal to or smaller than a predetermined allowable value;
• and
• a teaching point changing unit for, when the after-interchanged operational program including the teaching points adjusted by the position adjusting unit is executed by simulation, if cycle time of the executed after-interchanged operational program is longer than the initial cycle time stored in the initial storage unit, changing the adjusted teaching points to be the initial teaching points to adopt the initial teaching sequence.