電容式可撓性觸覺感測陣列的研製

A Flexible Tactile Sensing Array Based on Novel Capacitance Mechanism

黃信華(Xin-Hua Huang)

指導教授 ： 楊燿州

國立臺灣大學/工學院/機械工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.02909

摘要

本研究提出一創新性電容感測器結構，可應用於可撓式觸覺感測陣列。此新式的設計，除了製造程序簡易，更具有高可靠度的特性。本研究之電容式觸覺感測陣列的製造技術，是採用微機電製程及軟性電路板技術製作而成，其感測元件以聚二甲基矽氧烷 (Polydimethylsiloxane, PDMS) 與聚亞醯胺 (Polyimide, PI) 構成其主要結構材質與可撓性基材。電容式觸覺感測器由上層浮動電極與下層感測電極所構成，浮動電極使用微機電製程之方式製造。首先，以微機電技術之微影製程製作SU-8母模，隨後進行PDMS翻模以製作出可撓性PDMS結構層，再蒸鍍金屬於PDMS結構層作為浮動電極，感測電極與線路則利用軟性電路板技術製作完成。為了提升測量感測器效能之精準度與有效性，本研究架設一自動化電容量測平台，該量測平台針對電容式觸覺感測器施加壓力並進行電容與位移之測量，並使用LabVIEW®圖控程式軟體整合，透過各種傳輸介面如RS-232、GPIB、DAQ卡，達到自動化量測電容式觸覺感測器之目的，以評估感測器之效能。另外，本研究使用微機電系統模擬軟體Coventorware®，模擬電容式觸覺感測器受力時之電容以及位移變化，並將模擬與量測結果進行比較驗證。本研究針對製作之不同大小的感測器單元進行測量，如4.5×4.5 mm2，3×3 mm2 與1.5×1.5 mm2，其敏感度分別為0.55%/kPa、0.15%/kPa 與0.03%/kPa。研究中亦開發電容式觸覺感測陣列之掃描電路，並成功擷取到以不同形狀之PMMA模塊壓印於8×8電容感測器陣列之圖形。

關鍵字

電容感測器 ； 觸覺感測陣列 ； 軟性電路板 ； 微機電製程 ； 浮動電極

並列摘要

In this work, we present the development of a reliable capacitive tactile sensing array by using simple fabrication processes. The sensing array, which consists of a micromachined polydimethlysiloxane (PDMS) structure and a flexible printed circuit board (FPCB), will be used as the artificial skin for robot applications. Each capacitive sensing element comprises two sensing electrodes and a common floating electrode. The sensing electrodes as well as the metal interconnect for signal scanning are implemented on the FPCB, while the floating electrode is patterned on the PDMS structure. This special design can effectively reduce the complexity of device structure and thus makes the device highly reliable and manufacturable. The characteristics of the devices with 4.5×4.5 mm2, 3×3 mm2 and 1.5×1.5 mm2 sensing elements are measured and discussed. The measured sensitivities for these three devices are 0.55%/kPa, 0.15%/kPa and 0.03%/kPa, respectively. The scanning circuit for capacitive sensing array are also designed and implemented. The tactile images induced by the PMMA stamps of different shapes are successfully captured by using a fabricated 8x8 array.

並列關鍵字

Capacitive tactile sensing array ； MEMS ； SU-8 ； PDMS

參考文獻

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