Rhino to RHINO2 Conversion Guide
Page 20
deceleration rates of 70% - 65%. 10km/h scooters require stopping times around 1.5 seconds,
requiring deceleration rates around 60%.
Acceleration rates should be programmed to be no higher than Deceleration rates for safety, and
the Forward Acceleration rates may also have to be lowered below the Deceleration rates to prevent
the front wheels lifting when accelerating up a slope.
The Reverse Deceleration rates should be less than the Forward Deceleration rates if the
corresponding Reverse Speed is lower than the corresponding Forward Speed to reduce the risk of
the front wheels lifting when decelerating while reversing down a slope. Note that in the Rhino
controllers, there is only one Acceleration rate and one Deceleration rate, but these rates are
affected by the maximum speed in the Forward or Reverse direction so the effective Reverse
Deceleration is automatically reduced with the Reverse Speed.
High Acceleration or Deceleration rates require high motor torques, which in turn require high
motor currents, particularly on slopes. The required currents are much higher for high-speed
scooters as the required torque requires a proportionally higher motor current. However if the
acceleration or deceleration rate is not adjusted for the speed of the scooter, the physical
acceleration rate (in metres per second per second) increases proportionally with the top speed of
the scooter, requiring a proportionally higher torque. These effects are multiplicative, so it is very
important to reduce the programmed acceleration and deceleration rates for the higher speed
vehicles.
In order to achieve the required stopping distances without requiring too high deceleration rates,
the Soft Start and Soft Stop parameters should only be set as high as necessary to control the
starting and stopping jerks. Setting the Soft Start Time parameter too high will delay maximum
deceleration and lead to a significantly increased stopping distance. Setting the Soft Finish
parameter too high will delay the final reduction to zero speed and delay the application of the park
brakes, and can also increase the distance that the scooter "creeps" down a slope when stopping on
a slope.
Throttle Neutral Offset
The RHINO2’s
Throttle Neutral Offset
is equivalent to the Rhino’s
Speed Pot Neutral
setting. This
setting accounts for any mechanical offset between the throttle neutral position and the centre
position of the throttle wiper. The offset is an absolute voltage above or below neutral
.
The default neutral value is dependent on the value of the
Throttle Type
parameter:
Wig-Wag and Uni-polar both have the default neutral value at 2.5 V.
Single-ended has its default neutral value at 0 V +
Minimum Throttle Voltage
.
In this case all negative values of
Throttle Neutral Offset
are ignored and all positive values
are multiplied by 2, which means that a Wizard setting of 0.5V will produce an actual neutral
offset of 1.0V.
Note
:
Use the HHP to calibrate the unit instead of setting a value manually. See 'Throttle calibration'
in section 4.1.1.3 of the RHINO2 Installation Manual for details.