MRI INFUSION PUMP Group Members Aman Ghotra Team

MRI INFUSION PUMP Group Members: Aman Ghotra – Team Leader Can Pi – Communicator Miguel Benson - BSAC Prakash Rao – BWIG Client: Dr. George Newman, Ph. D. Frank Hospod Advisor: John Webster, Ph. D.

OUTLINE • Problem Statement • Client’s Requirements • Designs 1 -3 – Spur Gear – Vane Pump – Peristaltic Pump • • Decision Matrix Stepping Motor Design Proposal Future Goals

PROBLEM STATEMENT • Current MRI compatible infusion pumps are syringe-driven • Limitations: a. Flexibility in programming b. Saline and gadolinium capacities (60 m. L and 60 m. L, respectively) c. Time Consuming www. medrad. com (~7 min)

CLIENT REQUIREMENTS The pumps must: • Be made of a non-ferrous material • Minimize gadolinium or saline waste • Deliver accurate flow rates • (0. 2 -4 m. L/s, ± 0. 02 m. L/s) • Be easily sterilized and durable • Be programmable • Sequence: saline→bolus →saline →infusion →saline • Manage time to produce consistent images • Attach to containers (60/180 m. L)

SPUR GEAR PUMP • A pair of matched gears rotate in opposite directions. • The air pockets created by the rotating gears draw in the liquids. • The fluid exit at the outlet of the gear. http: //www. mech. uwa. edu. au/DANotes/gears/meshing. html#top

PROS & CONS PROS CONS • Low cost • Simple • Reliable • Efficient • Hard to sterilize • Sanitizing solution • Replacement

VANE PUMP http: //www. animatedsoftware. com

VANE PUMP (cont. ) • Cost • Varies greatly • $174 - $2993 • Parts • Rotor • Vane plates • Casing http: //www. animatedsoftware. com/

PROS AND CONS Pros • Develops good vacuum • Good with thin liquids • Can change displacement and angle Cons • Complex • Not for thick liquids • Contamination possible • Hard to Clean

PERISTALTIC PUMPS • Flow rate controlled by roller clamp • Tube walls squeezed to form seal as roller moves along tube – More rollers increase accuracy http: //www. animatedsoftware. com/pumpglos/peristal. htm

PERISTALTIC PUMPS (cont. ) • Positive Displacement Pump • Used in a variety of medical applications http: //www. pump-manufacturers. com/suppliers/environmentalpumping. html

PERISTALTIC PUMPS (cont. ) • Accuracy decreases as tubing wears and loses flexibility • BUT, tubing will be changed after every patient • Very sterile – no external contact with fluid • Typical price range: $170+ http: //www. uspto. gov/

DESIGN EVALUATION Maintenance Efficiency Cost Accessibility Total Spur Gear 1 Pump 2 3 2 8 Vane Pump 1 3 1 1 6 Peristaltic Pump 3 3 2 3 11 0 – worst; 3 - best

STEPPING MOTORS • Converts electrical energy into motion • Characteristics: – Voltage = Torque – Low cost ($60 & up) – Easily programmable • C/C++ Program • Labview http: //eio. com/step-rot. html

DESIGN PROPOSAL Alternative: If we can’t find out how to deshield the pump/motor case: We will have the motor in the control room and connect this with the rest of the apparatus through the wall.

FUTURE GOALS • • • Work on budget with client Buy parts to assemble pump Buy an economical Stepper Motor Learn programming Figure out deshielding options/nonferrous materials

Questions?