Medical education has a strong need for palpation training in the dete
ction of subsurface tumors. A virtual reality training simulation was
created to address this need. Utilizing the Rutgers Master II force fe
edback system, the simulation allows the trainee to perform a patient
examination and palpate (touch) the patient's virtual liver to search
for hard regions beneath the surface. When the user's fingertips pass
over a 'tumor', experimentally determined force/deflection curves are
used to give the user the feeling of an object beneath the surface. A
graphical user interface was developed to facilitate navigation as wel
l as provide a training quiz. The trainee is asked to identify the loc
ation and relative hardness of tumors, and performance is evaluated in
terms of positional and diagnosis errors. The results of this trainin
g simulation are in agreement with biomechanical analysis. (C) 1997 El
sevier Science Ltd.