Design and development of a novel monolithic compliant XY stage with centimeter travel range and high payload capacity

This article proposes a novel monolithic compliant spatial parallel XY stage (SPXYS). An important feature of the SPXYS lies in that it can deliver centimeter travel range and sustain large out-of-plane payload while possessing a compact structure, which makes the SPXYS suitable for some special applications such as Ultra-Violet Nanoimprint Lithography and soft-contact lithography. Different from conventional compliant positioning stages, the proposed SPXYS consists of a monolithic spatial parallel linear compliant mechanism (SPLCM) driven by four matching designed voice coil motors (VCMs). The moving platform of the stage is connected to the base by four spatial prismatic-prismatic (PP) joints, which are enveloped from planar PP joint based on the position space reconfiguration (PSR) method to realize desired travel range, payload capacity and compact size. The mechatronic model of the SPXYS is established by integrated using matrix structural analysis (MSA) and the method of images. The design flow chart of the SPXYS is given based on the key parameter sensitivity analysis. Furthermore, a reified SPXYS is designed and manufactured. The analytical design of the stage is confirmed by experiments. The reified stage has a travel range of 20.4 x 20.6mm(2), a compact structure with area ratio 1.87 %, and the resonant frequencies of the two working modes at 22.98 and 21.31 Hz. It can track a circular trajectory with the radius of 4.5 mm. The root mean squares (RMS) tracking error is 2 mu m. The positioning resolution is 100 nm. The payload capacity test shows that the reified stage can bear 20 kg out-of-plane payload.