All Publications


  • Design of a Roller-Based Dexterous Hand for Object Grasping and Within-Hand Manipulation Yuan, S., Epps, A. D., Nowak, J. B., Salisbury, J., IEEE IEEE. 2020: 8870-8876
  • Scaling of the performance of insect-inspired passive-pitching flapping wings JOURNAL OF THE ROYAL SOCIETY INTERFACE Wu, K., Nowak, J., Breuer, K. S. 2019; 16 (161): 20190609

    Abstract

    Flapping flight using passive pitch regulation is a commonly used mode of thrust and lift generation in insects and has been widely emulated in flying vehicles because it allows for simple implementation of the complex kinematics associated with flapping wing systems. Although robotic flight employing passive pitching to regulate angle of attack has been previously demonstrated, there does not exist a comprehensive understanding of the effectiveness of this mode of aerodynamic force generation, nor a method to accurately predict its performance over a range of relevant scales. Here, we present such scaling laws, incorporating aerodynamic, inertial and structural elements of the flapping-wing system, validating the theoretical considerations using a mechanical model which is tested for a linear elastic hinge and near-sinusoidal stroke kinematics over a range of scales, hinge stiffnesses and flapping frequencies. We find that suitably defined dimensionless parameters, including the Reynolds number, Re, the Cauchy number, Ch, and a newly defined 'inertial-elastic' number, IE, can reliably predict the kinematic and aerodynamic performance of the system. Our results also reveal a consistent dependency of pitching kinematics on these dimensionless parameters, providing a connection between lift coefficient and kinematic features such as angle of attack and wing rotation.

    View details for DOI 10.1098/rsif.2019.0609

    View details for Web of Science ID 000504648200007

    View details for PubMedID 31847758

    View details for PubMedCentralID PMC6936037