All robot components rely on a mobile robot’s base; a good
design need not be complex. I wrote
an article for SERVO discussing robot
mobility about four years ago,
however, some new and affordable
ready-made robot bases have come on
the market that I would like to discuss,
as well as offer some construction
tips. I’ll discuss what I believe are
some important facts to consider, but
you can always go to the Internet for
more information. I’m not going to
cover aerial or underwater vehicles as
these categories have their own
special design considerations.
Design Issues to
Contemplate
Quite a few configurations and
wheel arrangements are utilized in
mobile robots. The two most popular
wheel/steering configurations used in
mobile robot bases are Ackermann
steering and differential steering.
Ackermann steering is what is
called automobile type steering — two
wheels in the front (or back) that
steer right or left in order to change
the direction of the vehicle. I will
discuss this type more thoroughly later
as it is not as common for mobile
robots.
Robot bases and their
required structure are very
critical parts of mobile
robot design. In most
cases, these vital
components allow the
robot to perform more
complex functions such as
exploring its environment. I
know of many great robot
builders who can write
bug-proof code in their
sleep but literally cringe at
the task of designing a
base and structure for their
mobile robot. Cutting out
base parts, mounting
motors, and laying out
sensor locations frightens
many people, but these
parts can be made with
basic tools. You can cut
sheet stock to fabricate a
robot base or structure, or
you can actually construct
a base from beams and
parts such as the
articulated robot base
shown in Figure 1 built
with ActoBotics™
components.
Bases and Structure for
Mobile Robots
by Tom Carroll Then Now a n d
74 SERVO 12.2013
TWCarroll@aol.com
Figure 1. Robot base
built from ActoBotics
components.