Journal
JOURNAL OF BIONIC ENGINEERING
Volume 11, Issue 2, Pages 282-287Publisher
SPRINGER SINGAPORE PTE LTD
DOI: 10.1016/S1672-6529(14)60045-7
Keywords
woodpecker; anti-shock; frequency; modal analysis; stress spectrum
Funding
- National Natural Science Foundation of China [11272080]
- Doctoral Education Foundation of China Education Ministry [20110041110021]
Ask authors/readers for more resources
The mechanical properties of the skull and the anti-shock characteristics of woodpecker's head were investigated by experiment and numerical simulation. We measured the micro-Young's modulus of the skull by nano-indentation method and calculated the macro-equivalent Young's modulus of the skull at different positions using homogenization theory. Based on the Computerized Tomography (CT) images of woodpecker head, we then built complete and symmetric finite element models of woodpecker's skull and its internal structure and performed modal analysis and stress spectrum analysis. The numerical results show that the application of pre-tension force to the hyoid bone can increase the natural frequency of woodpecker's head. The first natural frequency under the pre-tension force of 25 N reaches 57 Hz, which is increased by 21.3% from the non-pre-tension state and is more than twice the working frequency of woodpecker (20 Hz 25 Hz). On the application of impact force to the tip of beak for 0.6 ms, high magnitudes of stress component occur at around 100 Hz and 8,000 Hz, far away from both the working frequencies and the natural frequencies of woodpecker head. The large gaps among the natural, working and stress response frequencies enable the woodpecker to effectively protect its brain from the resonance injury.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available