.
DRIVING
TESTS |
|
Assessment of a Transportable Mobility Aid in Severe Driving Conditions:
An Exploratory Test
Report No.: CV-90-03
Vehicle Technology Office Transportation
Technology and Energy Branch Ministry of Transportation (condensed
and reproduced with permission)
A severe driving test was conducted on a vehicle containing
a transportable mobility aid (a scooter) with a male anthropomorphic
dummy as a rider. A portion of the test was to see if the system
behaved in accordance with CSA D409 Standard. The remaining
portion of the test was to observe the behavior of the system
under high dynamic vehicle induced loading.
The test showed that the base of the scooter met the D409 standard.
However the displacement of the upper portions of the scooter,
which are not specified in D409, exceeded the displacements
of the base by a large margin. Under high dynamic loading, up
to 0.8 g lateral acceleration, the scooter responded with high
roll angles and large lateral swaying motions. It was found
that these were very sensitive to the manner in which the scooter
was secured, and the air pressure in the scooter tires. Loads
measured in the restraint system indicated that the restraints
were operating well under design limits.
This test was done to provide insight to the Canadian Standards
Association committee currently examining the D409 standard
regarding securement of this type of mobility aid.
Objective
The objective of this test is
to determine what severe driving tests can be performed on a
vehicle containing a restrained scooter and dummy that will
demonstrate the performance of the scooter and tie-down system.
Product Used
-
Ford Van E350
-
Everest & Jennings "Currette" mobility device
-
Q'Straint restraint system 50th percentile male anthromorphic dummy.
|
|
Test Philosophy and Methodology
The exploratory test subjected
the vehicle containing the scooter, a typical restraint system,
and a dummy seated on the scooter, to the three basic tests
described in CSA Standard CAN3-D409-M84, and a series of other
tests designed to generate high lateral or longitudinal accelerations
within the capability of the vehicle. The test program measured
the vehicle accelerations and attitude, the displacements of
the scooter, and some forces in the restraint system. The tests
did not have a pass/fail criterion. They were designed to demonstrate
the responses of a typical scooter relative to the vehicle as
a function of vehicle longitudinal or lateral acceleration.
The testing was conducted using a 50th percentile adult male
anthropomorphic dummy seated on the scooter. The dummy was secured
by a lap belt, and a left shoulder strap, parts of the restraint
system. The dummy's wrists were taped to the armrest of the
scooter, to represent a rider grasping the handlebars. The dummy
was not instrumented. It was however, the subject of a rear
facing video camera to show graphically the motion of the upper
torso. This is shown in an accompanying video movie of this
test.
It is not reported herein as data.
The test program included, as a baseline, the D409 tests of
straight-line acceleration, straight-line braking, and steady
lateral acceleration. The D409 tests were conducted strictly
in accordance with the standard.
The severe driving, or more aggressive tests at higher acceleration
levels, were divided into two parts and were as follows:
Lateral Loading
1. Double lane change
2. Spiral turn
3. Constant radius turn
4. J-turn
Longitudinal Loading
5. Abrupt braking
6. Snub braking
7. Back-up braking |
|
