Introducing Pneumatic Actuators in HapticTraining Simulators and Medical Tools

International audienceSimulators have been traditionally used for centuries dur-ing medical training as the trainees have to improve their skills beforepracticing on a real patient. Nowadays mechatronic technology has openthe way to more evolved solutions enabling objective assessment anddedicated pedagogic scenarios. Trainees can now practice in virtual en-vironments on various body parts, with current and rare pathologies, forany kind of patient (slim, elderly ...). But medical students need kines-thetic feedback in order to get significant learning. Gestures to acquirevary according to medical specialties: needle insertion in rheumatologyor anesthesia, forceps installation during difficult births ... Simulatorsreproducing such gestures require haptic interfaces with a variable ren-dered stiffness, featuring commonly called Variable Stiffness Actuators(VSA) which are difficult to embed with off-the-shelf devices. Existingsolutions do not always fit the requirements because of their significantsize. In contrast, pneumatic technology is low-cost, available off-the-shelfand has a better mass-power ratio. Its main drawback is its non-lineardynamics, which implies more complex control laws than with electri-cal motors. It also requires a compressed air supply. Ampère researchlaboratory has developed during the last decade haptic solutions basedon pneumatic actuation, applied on a birth simulator, an epidural nee-dle insertion simulator, a pneumatic master for remote ultrasonography,and more recently a needle insertion under ultrasonography simulator.This paper recalls the scientific approaches in the literature about pneu-matic actuation for simulation and tools in the medical context. It isillustrated with the aforementioned applications to highlight the bene-fits of this technology as a replacement or for an hybrid use with classicalelectric actuators