In the context of telehealth, robotic approaches have proven a valuable solution to in-person visits in remote areas, with decreased costs for patients and infection risks. In particular, in ultrasonography, robots have the potential to reproduce the skills required to acquire high-quality images while reducing the sonographer's physical efforts. In this paper, we address the control of the interaction of the probe with the patient's body, a critical aspect of ensuring safe and effective ultrasonography. We introduce a novel approach based on variable impedance control, allowing real-time optimisation of a compliant controller parameters during ultrasound procedures. This optimisation is formulated as a quadratic programming problem and incorporates physical constraints derived from viscoelastic parameter estimations. Safety and passivity constraints, including an energy tank, are also integrated to minimise potential risks during human-robot interaction. The proposed method's efficacy is demonstrated through experiments on a patient dummy torso, highlighting its potential for achieving safe behaviour and accurate force control during ultrasound procedures, even in cases of contact loss.

翻译：在远程医疗背景下，机器人技术已被证明是针对偏远地区面对面就诊的一种有价值的解决方案，可降低患者费用和感染风险。特别是在超声检查中，机器人有潜力再现获取高质量图像所需的技能，同时减少超声医师的体力消耗。本文针对超声探头与患者身体交互的控制问题展开研究，这是确保超声检查安全有效实施的关键环节。我们提出了一种基于变阻抗控制的新型方法，允许在超声检查过程中对柔顺控制器参数进行实时优化。该优化被表述为二次规划问题，并融入了从黏弹性参数估计中导出的物理约束条件。同时集成包含能量罐在内的安全性与无源性约束，以最大程度降低人机交互过程中的潜在风险。所提方法的有效性通过患者仿真躯干实验得到验证，表明其即使在接触丢失的情况下，也能在超声检查过程中实现安全行为和精确力控制。