用於人類無毛皮膚之電觸覺與機械觸覺回饋比較

Comparison of electro-tactile and mechanical-tactile feedback in human glabrous skins

林佑叡(Yu-Jui Lin)

指導教授 ： 陳湘鳳

國立臺灣大學/工學院/機械工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.01878

摘要

傳統提供觸覺回饋的裝置多數使用機械式的致動器，不僅需要耗費較多的能量且裝置體積不易微小化，提供振動或是力回饋時也可能伴隨著裝置共振的現象，降低觸感的真實性與使用者經驗。然而，與傳統提供回饋方式不同的電觸覺回饋能解決上述問題，且藉由不同刺激波形能提供不同觸覺感受。本研究利用電流刺激的方式來提供觸覺回饋，建立了一個電觸覺回饋系統，藉由Arduino開發版控制升壓電路中的數控電阻，因而得到不同電壓的輸出，並建立一個馬達H橋電路，用來控制刺激電流的流向，達到陽極、陰極以及雙相的電觸覺回饋。此外，本研究也建立一個由微型喇叭所構成的機械觸覺原型裝置系統，藉由輸入人類無毛皮膚敏感振動頻率與電壓，達到不同觸覺感受。
針對電觸覺極性與頻率分辨的部分進行使用者測試，結果發現極性正確分辨率達到80%，表示受試者幾乎能感受電觸覺極性的不同會有不同的感受;除了頻率50Hz之外，頻率正確分辨率大於70%，表示受試者幾乎能感受電觸覺頻率的差異。
本研究也進行電觸覺以及機械觸覺的感受評分測試，測試受試者對於這兩種回饋的各項感受，並調整機械振動的輸入頻率以及電壓大小，找尋機械觸覺回饋與電觸覺回饋摸起來相似之參數。透過這些參數能提供設計者設計出不同感受之電觸覺或是機械觸覺回饋裝置。

關鍵字

電觸覺回饋 ； 人類無毛皮膚 ； Arduino開發版 ； 升壓電路 ； 數控電阻 ； H橋電路

並列摘要

Traditional tactile feedback devices not only take more energy but also occupy more space. When these devices provide force feedback, devices may also be associated with resonance and reduce natural feeling and user experience. However, electro-tactile feedback is different from mechanical-tactile feedback, and it can solve the above problems. By using different stimulus waveforms, electro-tactile feedback can provide different tactile sensations. In this study, we use electrical stimulation to provide tactile feedback and create an electro-tactile feedback prototype device. Using Arduino to control the digit-control resistance in booster circuit, this prototype can output different voltages. We also establish an H-bridge circuit for controlling the flow of stimulation, and provide an anode, a cathode and a biphase electro-tactile feedback.
In addition, this study also established a mechanical haptic prototype device consisting of a micro-speaker, with the input of human glabrous sensitive vibration frequencies and voltages to achieve different tactile sensations. This study also conducted a user test for electrical polarity and frequency resolution. Results showed that subjects can distinguish different polarities up to 80% of accuracy. It means that with different electrical polarity, subjects have different electro-tactile feedback. Except the frequency of 50Hz, subjects can distinguish different frequency more than 70% of accuracy. It means that with different electricalfrequencies, subjects have different electro-tactile feedback.
This study also conducted electro-tactile and mechanical-tactile feedback rating test to test the subjects’s feelings for both feedback. By adjusting the input frequencies of the mechanical vibrations and voltage magnitudes, we found the parameters which mechanical tactile feedback is similar to the electro-tactile feedback. Designer can design the electro-tactile or mechanical-tactile feedback devices which provide different feelings through these parameters.

並列關鍵字

electro-tactile ； human glabrous skins ； Arduino ； booster circuit ； digit-control resistance ； H-bridge circuit

參考文獻

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