Design and control of an air-bearing supported three degree-of-freedom fine positioner. - Robert Hammer; Ralph L. Hollis; C. H. An; F. Henriks (ICRA, 1992)

Real and virtual coarse-fine robot bracing strategies for precision assembly. - Ralph L. Hollis; Robert Hammer (ICRA, 1992)

Accurate Alignment of Laminate Materials Using Sensor-Based Robot Techniques. - Andrew E. Brennemann; Robert Hammer; Ralph L. Hollis; William V. Jecusco II (ICRA, 1994)

Sensor based registration and stacking of electronic substrate layers. - Andrew E. Brennemann; Robert Hammer; William V. Jecusco II; Ralph L. Hollis (IEEE Robotics Autom. Mag., 1995)