Robotic catheter system

A robotic catheter system, the system comprising:

• a housing;
• a drive mechanism supported by the housing, the drive mechanism including an engagement structure configured to engage and to impart movement to a catheter device, the engagement structure defining a path for the catheter device, the engagement structure moveable between an engaged position in which the engagement structure engages the catheter device and a disengaged position in which the engagement structure does not engage the catheter device;
• and
• a biasing element configured to bias the engagement structure toward the engaged position, the biasing element aligned generally parallel to the path defined by the engagement structure;
• wherein the engagement structure includes a first wheel and a second wheel, wherein the second wheel is moveable relative to the first wheel to move the engagement structure between the engaged and disengaged positions.