Browsing by Author "Lin, Chu-Yi"

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A NOVEL MECHANICAL-MECHANISM ENHANCED THERMOMAGNETIC TWEEZER DEMONSTRATING GRIPPING OF FERROMAGNETIC AND NON-FERROMAGNETIC OBJECTS
(2016)
Wang, Hsin-Min
;
Chung, Tien-Kan
;
Chen, Chin-Chung
;
Cheng, Chih-Cheng
;
Lin, Chu-Yi
In this article, we demonstrate a mechanical-mechanism enhanced thermomagnetic tweezer. The tweezer which utilizes a thermal-magnetic-mechanical converting consists of two cross jointed Al arms, two Gd sheets, two NdFeB hard magnets, two thermoelectric generators (TEGs), and a ball bearing set. When comparing conventional thermomagnetic grippers, our thermomagnetic tweezer can grip either ferromagnetic or non-ferromagnetic objects and avoid producing temperature-influence to the gripped objects. Experimental results show that we can control TEGs to generate a temperature difference to operate the tweezer to grip small ferromagnetic objects (such as NdFeB hard magnet) and other non-ferromagnetic objects (such as PMMA bulk). The maximum gripping force produced by the tweezer operated by applying the DC current of 1.3 A with the voltage of 0.85 V is 0.59 newton. The corresponding gripping and releasing duration is 7.9 seconds and 8.1 seconds, respectively. According to these results, our tweezer would produce more practical objects-gripping applications.
A Novel Thermomagnetic-Actuated Gripper With a Piezoelectric-Pyroelectric Sensing Readout of Gripping States and Forces
(2017-10-01)
Chen, Chin-Chung
;
Chung, Tien-Kan
;
Lin, Chu-Yi
;
機械工程學系
;
國際半導體學院
In this paper, we reported a thermomagnetic-actuated gripper with a piezoelectric-pyroelectric sensing readout of gripping states and forces. The gripper consists of two CuBe cantilever beams, a Gd sheet, NdFeB hard magnets, a thermoelectric generator (TEG), a piezoelectric-pyroelectric PZT sheet, and a polymer-polymethyl methacrylate base. When TEG cools the Gd sheet lower than its Curie temperature, the magnetic attraction between the Gd sheet and the NdFeB magnets is produced due to the thermomagnetic property of the Gd sheet. Subsequently, the magnetic attractive force deflects two beams until beams contact to each other. Thus, the gripper can grasp a small object. Furthermore, when the gripper is operated to grasp the object, the piezoelectric-pyroelectric PZT sheet of the gripper produces voltage response. Through analyzing the voltage response, the gripping state is detected and subsequently the gripping force is obtained. After gripping, a negative dc current is applied to TEG to heat the Gd sheet higher than Gd's Curie temperature. Due to this, the magnetic attractive force is reduced and eventually eliminated. Consequently, the beams are separated due to their spring-back force. Thus, the gripper releases the object. The experimental results show that the gripper can be sequentially operated to grasp and release the object. Furthermore, as the current applied to the TEG is increased, the gripping force is increased. The maximum gripping force of the gripper is 0.69 N when a dc current of 0.7 A is applied. Moreover, when comparing conventional magnetic-field-actuated magnetic grippers, our gripper can be individually operated by applied currents, detect the gripping state, and sense the gripping force.