The PET scan infusion system is a mobile fluid injector used in hospital oncology wards. It provides a precise, flexible, safe, and efficient way to administer radioactive infusions for PET scan imaging. We were extensively involved in the development of the first-generation system, from early research with technicians and oncologists - which ensured a rich understanding of the users' needs - through detailed industrial design.For the second generation, we had the opportunity to make the PET scan infusion system more compact, thanks to changes in technology. With the product weighing over 600 lbs due to crucial radiation shielding, our client also sought to motorize the second-generation cart to make it easy for all users to operate and to better accommodate customers' space constraints. Our client provided us with a prototype motorized cart, for which we designed and constructed an ergonomic test rig with highly adjustable handles, allowing for experimentation with different ergonomic gripping and steering setups. We tested multiple configurations to determine the best. We also designed and prototyped several concepts for motor controls on the handles, arriving at the intuitive combination of a trigger-like safety switch and a thumbwheel for speed control, along with a governor switch that flips between two maximum speed settings - fast for long hallway travel and slow for careful maneuvers in a patient care room. We also developed ways to condense important product features to fit into the new, smaller cart. Finally, a new visual design was established. It built upon the appearance of the first generation cart to maintain brand continuity, yet emphasized the new, smaller size. It also defined a visual design language that could be carried forward into other upcoming products.