Segway RMP 210 V3, User Manual

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RMP 210
RMP 210
Endurance
Platform endurance is determined by measuring battery draw while performing various maneuvers.
In many cases the propulsion batteries will limit the runtime of the RMP. However, there are some scenarios in which the auxiliary
battery will be the limiting factor. Such cases include stationary operation and situations in which additional equipment is using the
auxiliary battery as a power source.
To calculate the energy used by a given maneuver, first determine the length of time the maneuver will be performed. Then multiply
that time (in hours) by the Watts used while performing the maneuver. This will give you the Watt-hours used per battery. Subtract
those Watt-hours from the Watt-hours remaining in the battery. Maximum battery capacity is 380 Watt-hours.
NOTICE
In the equations below, Power Draw (W) represents how much power is used by a single propulsion battery. Because every propulsion
battery will deplete at roughly the same rate, it is safe to assume this single battery is representative of all propulsion batteries.
Stationary Power Usage
When the RMP is maintaining a stationary position on level ground, the auxiliary battery is the limiting factor when calculating
runtime. The internal RMP components use approximately 16 Watts, allowing the auxiliary battery to last nearly 24 hours.
In contrast, the propulsion motors require only 4.5 Watts to maintain position on level ground, leaving 84% SOC left in the
propulsion batteries after 24 hours. During actual use, the power used by the propulsion batteries may be greater, especially if
maintaining position on a slope.
Straight Line Power Usage
The following empirical relationship can be used to provide a rough
estimate of power usage when travelling in a straight line. These
relationships are based on tests performed on dry, level pavement,
with tire pressure at 15 psi, and represent best-case scenarios.
Actual performance may vary.
Straight line power draw:
W = V (0.082 P + 43) + 4.5
W = Power Draw (Watts)
V = Velocity (m/s)
P = Payload Weight (lbs)
This equation describes the power usage while travelling at
constant speed. When accelerating and decelerating, the RMP will
momentarily draw significantly more power.
Turn-in-Place Power Usage
The following empirical relationship can be used to provide a rough
estimate of power usage when turning in place. This equation is
based on tests performed on dry, level pavement, with tire pressure
at 15 psi, and represent best-case scenarios. Actual performance
may vary.
Turn-in-place power draw:
W = V (0.097 P + 15) + 0.0009 P
2
+ 14
W = Power Draw (Watts)
V = Velocity (m/s)
P = Payload Weight (lbs)
Figure 13: Straight Line Power Usage at 15 psi
Figure 14: Turn-in-Place Power Usage at 15 psi