![](bg6.png)
consigns several simulations on testing efficient
snake locomotion for different speed profiles.
4 CONCLUSIONS AND FUTURE
WORK
The dynamics framework for the modelling and
simulation of non-wheeled snake-like robots has
been presented. Bio-inspired kinematics locomotion
was efficiently integrated into our approach of
achieving efficient serpentine locomotion at high-
speeds. Simulation results depicted in Table II
showed that our first hypothesis was indeed correct.
Considering speeds up to 4 m/s we obtained efficient
motion (less than 30%) of power loss due to friction.
For speeds >4m/s, this efficiency decreases because
of the increase of the angular speed, which also
makes the friction force increases and subsequently
generating more power loss average that makes the
control effort too energetic. This speed boundary
was obtained from several simulations performed in
Figures 4 and 5. In conclusion, the key aspects in
regarding energy efficient serpentine locomotion are
basically synthesized as:
1).
is an increasing
function of
, thus, the snake robot should
undulate with larger amplitude when the friction
ratio is larger (i.e. the snake-like robot tends to slip
in the normal direction), 2).
is basically a liner
function of the linear speed
, and, 3).
is a
decreasing function of n.
Figure 7: Locomotion testing experiments over different
friction terrains.
These relationships are useful for determining the
optimal control law for the snake robot. Upcoming
work is oriented towards the full implementation of
the hardware/software that allow the snake robot to
be fully controlled. Using a first prototype depicted
in Figure 7, our current work is focused on
researching which materials and shapes of the
snake’s skeleton generate the proper friction and
traction using our modeling approach.
ACKNOWLEDGEMENTS
This work is funded by the project ROBOCITY
2030 (S2009/DPI-1559).
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