Paired-EMS:通過刺激拮抗肌肉對增強基於電擊肌肉刺激(EMS)的力回饋體驗

Abstract

肌肉電擊刺激 (Electrical Muscle Stimulation, EMS) 已成為一種重要的可穿戴式觸覺回饋技術，能夠模擬多種虛擬環境中的力回饋體驗，例如拳擊衝擊力、虛擬物體的重量以及手推牆時的反作用力。為了模擬這些外力事件，EMS往往刺激使用者實際激活的肌肉對面的肌肉（即拮抗肌），導致不自主的肌肉收縮和與現實世界不同的觸覺感受。在本研究中，我們提出了「Paired-EMS」的方法，同時刺激使用者激活的肌肉和先前EMS刺激的肌肉（即拮抗肌肉對），以增強外力回饋體驗。我們首先進行了一項小型的實驗 (n=8)，以幫助設計肌肉對的刺激強度，然後進行了一項使用者體驗實驗，評估「Paired-EMS」與先前EMS方法在靜力 (isometric) 和動力 (isotonic)下使用者操作中的表現。實驗結果 (n=32) 顯示，「Paired-EMS」顯著提高了真實感、和諧感和娛樂性 (p<.05)，且舒適度結果相似 (p>.36)，總體上有 78% 的參與者更喜歡「Paired-EMS」(p<.01)。

Electrical Muscle Stimulation (EMS) has emerged as a key wearable haptic feedback technology capable of simulating a wide range of force feedback, such as the impact force of boxing punches, the weight of virtual objects, and the reaction force from pushing on a wall. To simulate these external forces, EMS stimulates the muscles that oppose (i.e. antagonistic to) the actual muscles that users activate, causing involuntary muscle contraction and haptic sensations that differ from real-world experiences. In this work, we propose Paired-EMS which simultaneously stimulates both the muscles that users activate and that prior EMS stimulates (i.e. antagonistic muscle pairs) to enhance the external force feedback experience. We first conducted a small formative study (n=8) to help design the stimulation intensity of muscle pairs, then conducted a user experience study to evaluate Paired-EMS vs. prior EMS approaches for both isometric and isotonic user actions. Study results (n=32) showed that Paired-EMS significantly improved realism, harmony, and entertainment (p<.05) with similar comfort (p>.36), and was overall preferred by 78% of participants (p<.01).