[PAR] [TLE] Train (roller coaster) [SEP] A roller coaster train is a vehicle made up of two or more cars connected by specialized joints which transports passengers around a roller coaster's circuit. [PAR] [TLE] Underfriction [SEP] On a roller coaster train, the underfriction, up-lift, or up-stop wheels are a device to keep the train from jumping off the track under intense movement.  The design was patented in 1912 by John Miller.
[PAR] [TLE] Train ( roller coaster ) [ SEP ] A roller coaster train is a vehicle made up of two or more cars connected by specialized joints which transports passengers around a roller coaster 's circuit . [PAR] [TLE] Underfriction [ SEP ] On a roller coaster train , the underfriction , up - lift , or up - stop wheels are a device to keep the train from jumping off the track under intense movement . The design was patented in 1912 by John Miller .
Who designed the rollercoaster train that involved underfriction?
Who designed the rollercoaster train that involved underfriction ?
John Miller
John Miller