The First Agricultural Tractor Roll-Over Protection Structure (Rops) In The USA Resulted From Research By Lloyd H. Lamouria, Ralph R. Parks And Coby Lorensen At The Agricultural Engineering Department Of The University Of California At Davis. It Was Designed And Successfully Tested In The Summer Of 1956. It Was Exhibited And Reported At The Annual Meeting Of The Pacific Coast Section Of The American Society Of Agricultural Engineers (ASAE) In December 1956. Warren I. Hanson, Safety Coordinator, N. Dakota Highway Dept., Took The Next Bold Step In Early 1959, When He Instigated A Program That Resulted In Seven Rops Being Built On Tractor Mowers That Year, And In 1960 All 190 Were So Equipped.

Wesley F. Buchele Then Organized The First Rops Symposium At The ASAE Winter Meeting, Dec. 1962, Which Recommended Their Immediate Adoption. Charles S. Morrison Of Deere & Company Began Commercial Development Of The Agricultural Rops. Merlin Hansen Supervised The Design And Development Of The Rops By John Edman, R.D. Miller, Dave Bucher And Others At The John Deere Product Engineering /P, Waterloo, Iowa. Deere's Unique Two-Post Rops Design Made The Structure More Compatible With Farm Implements, Such As Front-End Loaders And Cultivators. With The First Announcement Of The "Roll-Gard" With Seat Belts On June 4, 1966, Affordable Operator Protection With Proven Performance Was Made Available To Customers.Patent Rights And Engineering Data Were Donated To The Public. Under The Leadership Of Merlin Hansen, The Design Became An Industry Standard. Operator Acceptance Of The Rops Was Further Increased By Incorporating It Into An Environmentally-Controlled Cab. Use Of This Agricultural Tractor Rops Has Proven To Be Effective In Reducing Serious Injuries To The People Who Have Made American Agricultural Productivity The Envy Of The World. Dedicated By The American Society Of Agricultural Engineers 1986