Page 111 - Build Your Own Combat Robot

Build Your Own Combat Robot
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You should use only multi-stranded wires—the more strands, the better. Do
not use solid core wires because they have the tendency to break due to the vibra-
tions and impacts within the robot. Most wires use PVC for the insulation; but for
higher temperature handling capability and flexibility, use wires with Tefzel,
Kapton, Teflon, or Silicone insulation.

B attery Types

Sealed lead acid (SLA), nickel cadmium (NiCad), and nickel metal hydride
(NiMH) batteries can be successfully used for competition. Two other battery
types worth mentioning are the Lithium Ion and the Alkaline types. Although not
recommended, these two battery types are common enough that some people
might consider using them in their robots.
In most competition robot contests, the regular lead acid batteries that are used
on automobiles, boats, and motorcycles are prohibited because these batteries al-
low access to the internal liquids, and they can leak acid if they are turned upside
down or if they become damaged—which can also damage the arena and pose a
safety hazard. The lead acid batteries that are allowed in these events are called
sealed lead acid batteries, because they have no ports for checking the internal fluids
and they can be operated in any orientation (see Figure 5-5). These batteries are often
called Gel-Cells, immobilized lead acid batteries, or glass-mat lead acid batteries.

FIGURE 5-5
A sealed lead acid
battery. (courtesy
of Hawker
batteries)