Method and system for using a buffer to track robotic movement

A system for controlling an automated machine comprising;

• a controller coupled to the automated machine, the controller receiving movement commands as a plurality of steps that place the automated machine into one of a plurality of states;
• a control computer coupled to the controller, the computer having a memory and a processor, the computer comprising:
• a buffer residing in the memory, the buffer storing a current step executed in the movement of the automated machine and a predetermined number of previous steps;
• and
• an automated control program running in conjunction with the processor, the automated control program operable to determine a next step to be executed from a choice of more than one step, based on the identity of a previous step and send the next step to the controller as a next movement command.

A method for controlling movement of a robot arm in a semiconductor processing tool comprising:

• defining a buffer of a predetermined size, the buffer storing the previous steps in the movement of the robot arm;
• executing a step in the movement of the robot arm;
• checking to see if the step executed in the movement of the robot arm is the same as a predetermined step of interest;
• checking the buffer to determine what at least one previous step was, if the step is the predetermined step of interest;
• and
• executing a new step in the movement of the robot arm, if the step is the predetermined step of interest, the new step executed depending on what the at least one previous step was.

A system for controlling a robot arm in a semiconductor processing tool comprising:

• a robot controller coupled to the robot arm, the robot controller receiving movement commands as a plurality of steps that place the robot arm into one of a plurality of states;
• and
• a control computer coupled to the robot controller, the control computer having a memory and a processor, the control computer comprising:
• a buffer residing in the memory, the buffer storing the current step executed in the movement of the robot arm and a predetermined number of previous steps;
• and
• a robot control program running in conjunction with the processor, the robot control program operable to determine the next step to be executed from a choice of more than one step based on the identity of a previous step.

A control computer for controlling movement of an automated machine, the control computer having a memory and a processor, the control computer comprising:

• a buffer residing in the memory, the buffer storing current step executed in the movement of the automated machine and a predetermined number of previous steps;
• an automated control program running in conjunction with a processor, the automated control program operable to:
• formulate a signal indicative of the current step in the movement of the automated machine;
• send the signal to a robot controller;
• check the current step against one or more previous steps stored in the buffer;
• and
• determine a next step based on identity of one or more previous steps.

A computer readable medium employing a software program for controlling movement of an automated machine, the software program comprising:

• program code configured to form a buffer, the buffer storing a current step executed in the movement of the automated machine and a predetermined number of previous steps;
• program code configured to determine if a current step is a step of interest;
• program code configured to access the buffer and determine identity of at least one previous step, if the current step is the step of interest;
• and
• program code configured to determine a next step to be executed from a choice of more than one step, based on the identity of the at least one previous step, if the current step is the step of interest.