Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6912903 | Soil compaction measurement | William Hamblen, Evan F. Berkman | 2005-07-05 |
| 6604432 | Soil compaction measurement | William Hamblen, Frank Berkman | 2003-08-12 |
| 5796849 | Active noise and vibration control system accounting for time varying plant, using residual signal to create probe signal | Ronald Bruce Coleman, Roy Allen Westerberg | 1998-08-18 |