Rotary Chair Nydiag 200
Page
20
First, press “Zero Position” button in the lower left corner of the Rotary Chair Control window.
1. Position: Enter a value such as 45, 90, 135 or similar in the Position p: box and press
“Start”.
Measure the number of degrees of movement
–
must equal the value entered in
‘Position p:’
box.
2. Velocity: Check that velocity changes with different values entered in the Velocity v: box
–
low values produce slow movements and high values produce fast movements.
Enter the value „20‟ in the
‘Velocity v:’
box and press “Start” button.
Allow the chair to accelerate up to set velocity (approx. 2 seconds with acceleration set at
10°/s²) and measure the time consumed for a full circle. Should be 18 seconds at velocity
of 20 °/s
In order to obtain sufficiently long cycles it may be necessary to enter high values such as
720 in Position p: box
–
this will give at least 2 full circle rotations for measurement.
3.
Acceleration: check that low values (such as 10°/s²) produce soft acceleration, whereas
high values (such as 50°/s²) produce abrupt acceleration.
Enter the following values:
i.
Position
=
720
ii.
Velocity
=
100
iii.
Acceleration
=
20
Expected acceleration time is 5 seconds
–
check using a stop watch
Maximum acceleration is 100°/S² and must never exceed this value.
6.3 Set velocity function
In the
Set Velocity
mode the chair is rotated at a constant, pre-defined velocity until it is stopped
via th
e “Stop” button.
Once the acceleration phase is completed the chair will have reached its target velocity which it
will keep until the “Stop” button is activated.
Relevant VO25 test protocol: Data from
Set Velocity
can be recorded and analyzed in the
StepRotation test
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