Robotics and Automation Expert

Performance Criteria Optimization (page 4)

Performance Criteria 

We have formulated and implemented in software over 30 performance criteria (Van Doren and Tesar, 1992). These criteria emphasize task-based performance indicators derived from the physical description of the manipulator. These formulations emphasize efficiency and portability. With currently available computational hardware, decisions based on several of these criteria are possible in real-time. Given the rapid pace of advancements in computational speed, we feel that it will soon be possible to employ the entire suite of performance criteria in a real time decision making process. Table 1. lists the general categories of these performance criteria. Our continuing work focuses on issues of normalization and multiple criteria fusion. 

Elementary physical limitations form the basis for the constraint criteria. These limitations restrict joint 
travels, joint speeds, joint accelerations, and joint torques. The joint travel availability is a 
representative criterion that seeks to keep the joint displacements as near as possible to the midpoints of 
their travel. 

The Jacobian matrix forms the basis for the geometric performance criteria. These criteria are task 
independent and based only on the geometry of the robot, thus these criteria are formulated once for 
eachrobot with no need for reformulation if the task changes (Cleary and Tesar, 1990). 

The inertial performance criteria have their basis in dynamic models of forces and torques within the robot 
and are essential to the intelligent design and application of robots. The rate of change of inertialcriteria 
measure how fast the robot can respond to torque and force demands. They are especially important because larger actuators or higher gear ratios can supply more torque, but both will slow the overall response of the robot to external disturbances. 

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