| Description: |
Fig. 9. Virtual and physical hydrostatic models of Baculites compressus with computed percentage of the phragmocone emptied for neutral buoyancy (Φ) and hydrostatic stability (St). Green, soft body; grey, shell; red, gas; blue, liquid; yellow, PLA plastic; purple, bismuth counterweight; B, center of buoyancy; M, center of mass. A. Virtual model with an even distribution of cameral liquid and gas in the phragmocone (center of mass of cameral liquid and gas = center of volume of the phragmocone; cameral liquid and gas not shown). B. Modified virtual model with simplified internal geometry ("Modified 1" in Table 3). C. Neutrally-buoyant, 3D printed model. D. Modified virtual model with simplified internal geometry and axel hole through pivot point of rotation ("Modified 2" in Table 3). E. Neutrally-buoyant, 3D printed model fixed to an axel and silicone tubing used to supply thrust in the ventral direction. For this model, the mass discrepancy (Table 5) resulted in a slightly lower of 97.3%, but was held constant at 100%. All computed errors in St were computed assuming that the total mass discrepancy was distributed in the positive or negative z-directions. ; Published as part of Peterman, David J., Ciampaglio, Charles N., Shell, Ryan C. & Yacobucci, Margaret M., 2019, Mode of life and hydrostatic stability of orthoconic ectocochleate cephalopods: Hydrodynamic analyses of restoring moments from 3D printed, neutrally buoyant models, pp. 441-460 in Acta Palaeontologica Polonica 64 (3) on page 453, DOI:10.4202/app.00595.2019, http://zenodo.org/record/13261616 |