A Robotic Urinary Bladder Enabling Volume Monitoring and Assisted Micturition

The urinary bladder is considered a highly complex organ, capable not only of storing urine but also of sensing intra-vesical volume and dynamically expanding and contracting. Consequently, fully replicating its functions following radical cystectomy remains a significant technological challenge. Hereinafter, an implantable robotic bladder is presented that can change shape and expand its internal volume up to 400 mL, based on the amount of urine collected from kidneys, and monitor the volume in real-time. It can apply on-demand mechanical compression to assist urination, by means of an origami-designed enclosure, coupled to miniaturized mechatronic components. In vitro characterization in a human phantom is demonstrated, and volume monitoring is validated following a realistic filling routine. The tests demonstrate successful expansions for collecting urine, with an average volume reconstruction error of 8.4 ± 6.1 mL, and then 99% of the volume is voided in less than 2 min. The work paves the way for developing active robotic solutions and reproducing bladder functions in patients with cancer and organ removal or impairment.