Mechanisms and methods for controlled volume injection into a soft media with concurrent pressure measurement

A volume controlled injection system comprising:

• a tubular conduit having a deformable wall, the deformable wall defining a central channel extending between first and second ends of the tubular conduit, wherein the channel defines a volume suitable for containing a fluid therein, wherein the volume of the channel decreases upon exterior compression of the deformable wall;
• an actuator configured to compress the deformable wall by symmetrically impinging opposing sides of the deformable wall along an axis lateral to a central longitudinal axis of the tubular conduit;
• and
• a controller configured to control movement of the actuator,
• wherein the actuator is configured to move a distance to deflect the deformable wall toward the central longitudinal axis and reduce the volume of the channel such that a corresponding volume of fluid is displaced from the central channel through an outlet at the second end of the tubular conduit, and
• wherein the controller is configured to control the distance based on a predetermined relationship between actuator movement and a volume of fluid displaced from the tubular conduit.

A method for measuring elastic properties of soft material comprising:

• providing a conduit having a deformable wall defining a channel pre-filled with an incompressible fluid;
• inserting an outlet needle of the conduit into a soft material;
• deflecting an exterior portion of the deformable wall by displacement of an actuator to reduce the inner volume of the channel and introduce a body of incompressible fluid into the soft material from the conduit over an operation period of time;
• recording an internal pressure of the conduit over the operation period of time;
• determining an expansion of the body of incompressible fluid over the operation period of time based on a volume change of the body of incompressible fluid over the operation period of time;
• and
• determining an elastic property of the soft material based on a predetermined relationship between a displacement distance of the actuator, the expansion of the body of incompressible fluid, and the internal pressure of the conduit during the operation period of time.