IEEE Trans Haptics. 2017 Oct-Dec;10(4):567-579. doi: 10.1109/TOH.2017.2679000. Epub 2017 Mar 7.
Despite the fact that conventional haptic interfaces and rendering algorithms commonly approximate interactions with force only, the dynamic effects of even simple tasks, e.g., writing on a paper, involve both forces and torques. To extend previous algorithms as well as to investigate the effects of torque feedback on human roughness perception, we deployed a novel haptic platform with two probes, fingertip and penhandle. Three torque conditions were examined: 1) Slope Torque, which orients the probe perpendicular to the surface, 2) No Torque, where no active torque is provided by the device, and 3) Stiff Torque, where torque feedback is provided to keep the probe upright. A conventional magnitude estimation experiment was performed. The results indicated that both the torque signals and grasp type mediate human perception of virtual textures. Slope Torque led to greater perceived roughness when the fingertip was used, and the fingertip led to higher roughness ratings than the penhandle with the Slope Torque condition. The Slope Torque algorithm appears to be advantageous for generating rougher surfaces compared to the force-based algorithms which are typically limited by the system stability and actuator saturation.
尽管传统的触觉接口和渲染算法通常仅近似于力的交互，但即使是简单任务（例如在纸上书写）的动态效果也涉及力和扭矩。为了扩展以前的算法并研究扭矩反馈对人类粗糙度感知的影响，我们部署了一个带有两个探头（指尖和笔杆）的新型触觉平台。检查了三种扭矩条件：1）斜率扭矩，使探头垂直于表面定向，2）无扭矩，设备不提供主动扭矩，3）刚性扭矩，提供扭矩反馈以保持探头垂直。进行了常规的幅度估计实验。结果表明，扭矩信号和抓握类型都可以调节人类对虚拟纹理的感知。当使用指尖时，斜率扭矩会导致更大的粗糙度感知，并且与具有斜率扭矩条件的笔杆相比，指尖会产生更高的粗糙度等级。与通常受到系统稳定性和执行器饱和限制的基于力的算法相比，斜率扭矩算法似乎更有利于生成更粗糙的表面。
