Characterizing Stairmill Ascent with Pelvic Applied Forces

Stair climbing is a common activity encountered in daily living. Stair ascent is a demanding task that requires a large range of motion of the joints, strong muscle strength, good cardiovascular fitness, and fine balance control. Given this, the activity can be difficult for different populations that lack muscle strength and coordination. To train and assist people in this activity, several robotic platforms have been proposed, but these limit the natural motion of the individual. For example, these devices fix the placement of the feet and reduce the natural swing of the lower limbs. This makes it difficult to manipulate the center of mass, which is crucial to stair ascent. In this dissertation, we present a novel parallel cable-driven platform in which the end effector is the user’s pelvis; the stairmill tethered pelvic assist device. This architecture allows the user to retain their natural movement and relation between the feet and the center of mass, all while applying three dimensional forces on the pelvis during continuous stair ascent on a revolving stairmill. In this work, we show the design, fabrication, and validation of this robotic system. Various force strategies were explored during stairmill ascent using this robotic platform. A characterization experiment was conducted to investigate gait performance and muscle coordination. Two simple interventions were tested to show the potential for long-term training program. This work sheds light on the different strategies of stair climbing and how we can use cable driven platforms to train and assist individuals during this challenging task. The knowledge gained by this work allows for the expansion of designing training paradigms for stair climbing with natural motion. These can assist individuals in improving their quality of life

Development of Electromagnetic Positioning Stage for Astigmatic Profilometer

隨著科技的蓬勃發展，各類研究領域對設備的性能需求也越來越多樣化。其中3D 表面輪廓量測技術在表面觀察量測部分，可以了解表面因物理或化學作用而產生的起伏程度。DVD 像散式讀取頭具有判斷表面高低起伏的功能，近年來常應用於距離量測。此外，為了量測一定範圍的表面輪廓，致動平台的載運性能在表面輪廓儀中占有重要地位。本論文利用DVD 讀取頭的量測距離特性，結合以電磁致動原理設計的共平面雙軸致動平台，開發一體積緊緻的表面輪廓儀。電磁致動器為動圈式設計，利用導電線圈在磁場中產生的作用力來回運動，使用彈性膜做為懸吊與阻尼裝置，雙軸致動平台利用軸上兩端電磁致動器的推拉力使平台產生位移，藉由理論推導與模擬分析磁場強度、致動器出力、共振頻率與最大位移。 實驗探討電磁致動器在完整彈性膜與網狀彈性膜下對平台的影響，透過量測致動的位移量、線性度、解析度、重複性、共振頻率與交錯干擾得到平台性能。結合DVD 讀取頭與完整彈性膜雙軸致動平台之表面輪廓儀，應用於電路晶片與葉下表皮掃描，可在掃描速度20 Hz 驅動下得到掃描面積1 mm × 1 mm (500 × 500 像素)之表面輪廓。As the well-grown of technology, manifold functions of the equipment have developed on the surface measurement. 3D surface profile measurement can detect the sample surface structure due to physical or chemical effect. DVD pick-up head possess a function of nano-scale displacement measurement by the astigmatic method. In a profilometer, furthermore, the scanner performance is the most important to measure the surface profile. This study is to design and develop a compact profilometer using a coplanar biaxial positioning stage, which are driven by electromagnetic actuators, and the astigmatic DVD pick-up head to measure the surface profile. The electromagnetic actuator is a moving-coil design, and utilizes Lorentz force to move the coil constructed with the elastic layer back and forth. Every two electromagnetic actuators construct at opposite sides of the positioning stage for actuating the sample stage. Maxwell 13 and ANSYS 13.0 are used to simulate magnetic field, force and resonant frequency of the actuators. Experiments verify that the coplanar biaxial stage can achieve a maximum stroke exceed 1 mm. The stage integrated DVD pick-up head could scan a 1 mm × 1 mm area (500 × 500 pixels) of IC and epidermis at scanning rate 20 Hz.口試委員會審定書 I 誌謝 II 中文摘要 III 英文摘要 IV 目錄 V 圖目錄 VII 表目錄 IX 符號表 X 第一章緒論 1 1.1 研究背景與動機 1 1.2 文獻回顧 2 1.3 研究目標 6 1.4 內容簡介 7 第二章雙軸電磁致動平台設計開發 8 2.1 電磁致動器概念設計 9 2.2 電磁致動器之磁場理論分析與模擬 12 2.3 雙軸致動平台概念設計 16 2.4 致動平台理論分析 17 第三章、雙軸電磁致動平台性能測試 22 3.1 量測實驗架構 22 3.2 致動性能量測 23 3.2.1 驅動電壓對位移量之影響 23 3.2.2 驅動頻率對位移量之影響 30 3.2.3 單軸驅動下交錯干擾的影響 35 第四章輪廓儀開發與性能測試 38 4.1 像散式讀取頭量測原理 38 4.2 像散式輪廓儀性能測試 39 4.2.1 電路晶片掃圖結果 42 4.2.2 葉下表皮組織掃描結果 44 第五章總結與未來展望 46 參考文獻 47 附錄A:釹鐵硼(NdFeB)磁石B-H 曲線50 附錄B:計算磁路空間的磁漏率 5

A novel neck brace to characterize neck mobility impairments following neck dissection in head and neck cancer patients

Abstract Objective This article introduces a dynamic neck brace to measure the full range of motion (RoM) of the head–neck. This easy-to-wear brace was used, along with surface electromyography (EMG), to study changes in movement characteristics after neck dissection (ND) in a clinical setting. Methods The brace was inspired by the head–neck anatomy and was designed based on the head–neck movement of 10 healthy individuals. A 6 degrees-of-freedom open-chain structure was adopted to allow full RoM of the head–neck with respect to the shoulders. The physical model was realized by 3D printed materials and inexpensive sensors. Five subjects, who underwent unilateral selective ND, were assessed preoperative and postoperative using this prototype during the head–neck motions. Concurrent EMG measurements of their sternocleidomastoid, splenius capitis, and trapezius muscles were made. Results Reduced RoM during lateral bending on both sides of the neck was observed after surgery, with a mean angle change of 8.03° on the dissected side (95% confidence intervals [CI], 3.11–12.94) and 9.29° on the nondissected side (95% CI, 4.88–13.69), where CI denotes the confidence interval. Axial rotation showed a reduction in the RoM by 5.37° (95% CI, 2.34–8.39) on the nondissection side. Neck extension showed a slight increase in the RoM by 3.15° (95% CI, 0.81–5.49) postoperatively. Conclusions This brace may serve as a simple but useful tool in the clinic to document head–neck RoM changes in patients undergoing ND. Such a characterization may help clinicians evaluate the surgical procedure and guide the recovery of patients