CATHETER DEFLECTION CONTROL ASSEMBLY

An apparatus includes a handle, a catheter, an end effector, and a deflection drive assembly. The end effector includes at least one electrode. The deflection drive assembly includes an input member, a translating assembly coupled to the end effector, and a rack and pinion assembly. The rack and pinion assembly is configured to drive the translating assembly to deflect the end effector away at an angle relative to the longitudinal axis and consists of a rack and a pinion. The rack and pinion assembly is configured to either transfer rotational motion of the pinion from the input member into linear motion of the rack to push distally or pull proximally the translating member; or transfer linear motion of the rack from the input member into rotational motion of the pinion to move a first end of the translating member proximally and a second end of the translating member distally.