Mobility Characterization and Dynamical Analysis of a Surface Hopper for Low-gravity Environments

January 26, 2021

The growing scientific interest in the exploration of low-gravity celestial bodies, such as asteroids, comets, or small planetary satellites, has developed a higher need for mobile surface missions. Internally-actuated hopping systems provide an efficient and viable opportunity to achieve surface mobility under such environments, with low operational cost. The rover's actuation using flywheels, implements a high control, design flexibility, and enclosed mobility mechanism. Through self-righting maneuvers, fewer actuators are needed and a simpler single-axis hopping motion can be achieved. Throughout this thesis, the rover's hopping mobility based on these configurations is studied. The dynamical analysis and simulations performed provided important conclusions, and innovative new applications are proposed that show significant improvement on the hopper's operation and on the hop distance achieved for different surface inclinations. It is showed the interest of applying a variable spike angle configuration and a variable spike length configuration. The application of a spike that can adjust and control its angle improves significantly the hop distance achieved for different surface inclinations. The implementation of a spike that can change its length works as a trade-off solution between more efficient hops with shorter spikes and better transverse capability over higher obstacles with longer spikes. This later variation presents particularly a potential contribution to the landing stage, however a further study of this application is needed.

Authors in the community:

• 

  M

  Miguel Borges Pinheiro

  ist179108

Supervisors of this institution:

• 

  J

  João Manuel Gonçalves de Sousa Oliveira

  ist12909

• 

  R

  Rodrigo Martins de Matos Ventura

  ist13950

mechanical-engineering - Mechanical engineering

eng - English

Instituto Superior Técnico