A trocar assembly includes a trocar housing that defines a working chamber, and a cannula having a proximal end and a distal end and defining a lumen that extends between the proximal and distal ends. The cannula is coupled to the trocar housing at the proximal end to facilitate communication between the lumen and the working chamber. A plurality of compliant deflection devices are provided at or near the distal end of the cannula, and each compliant deflection device includes a radial biasing member that extends radially inward toward a centerline of the cannula to center a surgical tool within the lumen and minimize unintended oscillation and vibration of the surgical tool.