Fig. 2: Design of CS clinostat and polydimethylsiloxane (PDMS)-based clinostat dish.

a The CS clinostat generates a 360° three-dimensional (3D) rotation by using two motors that rotate an outer frame and an inner frame. The inner frame, outer frame, and base component are 3D-printed. Motor A, connected to the outer frame rotates at 4 rpm, and Motor B, connected to the inner frame, rotates at 1.8 rpm. The dimensions of the clinostat are 282 mm × 140 mm × 252 mm. The photograph of the CS clinostat is in an inset; the scale bar is 10 cm. b Schematic image and photograph of the PDMS clinostat dish. The top and side walls of the PDMS clinostat dish are made of PDMS, and the bottom is made of glass coated with gelatin. A hole with a diameter of 5 mm is located on the top surface of the PDMS clinostat dish for injecting medium and cell suspensions. The surface of the PDMS clinostat dish allows for gas exchange owing to the good permeability of PDMS; the scale bar is 20 mm. c Up to six PDMS clinostat dishes can be inserted inside the inner frame, the dimensions of which are 85 mm × 93 mm × 93 mm. The inserted PDMS clinostat dishes are fastened using a holder. The PDMS clinostat dishes are inserted symmetrically to achieve a symmetric culture environment. If the PDMS clinostat dishes are aligned asymmetrically, the applied acceleration force would not be symmetrical.