Augmented Haptic Based Medical Palpation Simulator

Updated: Oct 22, 2019

Augmented Haptics: Pneumatic Based Prostate Tumor Palpation Simulator

Abstract:

The currently available prostate palpation simulators are based on either a physical mock-up or pure virtual simulation. Both cases have their inherent limitations. The former lacks flexibility in presenting abnormalities and scenarios because of the static nature of the mock-up and has usability issues because the prostate model must be replaced in different scenarios. The latter has realism issues, particularly in haptic feedback, because of the very limited performance of haptic hardware and inaccurate haptic simulation. This paper presents a highly flexible and programmable simulator with high haptic fidelity. Our new approach is based on a pneumatic-driven, property-changing, silicone prostate mock-up that can be embedded in a human torso mannequin. The mock-up has seven pneumatically controlled, multi-layered bladder cells to mimic the stiffness, size, and location changes of nodules in the prostate. The size is controlled by inflating the bladder with positive pressure in the chamber, and a hard nodule can be generated using the particle jamming technique; the fine sand in the bladder becomes stiff when it is vacuumed. The programmable valves and system identification process enable us to precisely control the size and stiffness, which results in a simulator that can realistically generate many different diseases without replacing anything. The three most common abnormalities in a prostate are selected for demonstration, and multiple progressive stages of each abnormality are carefully designed based on medical data. A human perception experiment is performed by actual medical professionals and confirms that our simulator exhibits higher realism and usability than do the conventional simulators.

We built a prostate palpation simulator where a medical practitioner train his/herself a process called Digital Rectal Examination (DRE). Where conventional mock-up-based training simulators can only provide a fixed number of abnormal conditions, our simulator is capable of creating various prostate abnormalities ranged from a single small tumor to multiple larger tumors, with comparable fidelity and realism.

we have developed a new prostate-shaped end-effector that systematically changes the its shape and stiffness using pneumatic and particle jamming techniques with embedded balloon. At current stage, seven pores are embedded in the silicone prostate mock-up, so a medical practitioner can perceive tumors with wide range of stiffness, position, and number.

What doctors (professionals) says about this prostate palpation simulator?

When professionals compared our proposed prototype with other four commercial DRE training simulators. For the subjective comparison we invited five medical professional whose had good DRE experience in real-life. In this subjective evaluation, our proposed simulator have achieved the highest realism and high-fidelity.