A roller scanning type prostate palpation sensor system using a cantilever beam type force measurement

Palpation has been used for centuries in medicine as a screening and diagnosis modality for a number of pathological conditions. However, this technique is subjective since palpation sensitivity depends on the skill and experience of a medical examiner. An objective approach to acquire quantitative tactile information is needed. A roller scanning type palpation sensor system consisting of an x-axis linear slider and a palpation probe for detecting lumps in a soft object such as the prostate tissue is proposed and fabricated in this study. By translating the slider and changing the palpation angle of the probe, a chrome steel ball which was the contact component indented and scanned the surface of soft silicone phantoms embedded with hard lumps. Lumps were detected by measuring reaction force waveform fluctuations. Fundamental characteristics of the proposed sensor system were validated by comparison with the ground truth load cell output and showed a strong linear correlation with
$r^{2}=0.9985$
. On silicone samples with hard lumps, the system was able to detect lumps of various sizes embedded at the depth of 5mm. From the results, the proposed sensor system holds potential for tissue characterization.