Viraam said:4) I didnt understand what you mean by significant acceleration? (do you mean appreciable acceleration)
Acceleration
Most people understand that acceleration is the rate of change of velocity. The effects of acceleration are both physical as well as psychological and will have major variances between people traveling in the elevator. Elevator acceleration is perceived as good when it is constant. If the acceleration is by noticeable steps it will be perceived as objectionable.
Obviously when slowing down an elevator will produce a negative acceleration curve which should mirror the step-less acceleration curve.
The passenger perception of acceleration is that for values below 1.1 m/s2 the majority of passengers would not have any perception of a difference in overall elevator ride quality. Acceleration and motion is noticeable if between 1.3 m/s2 and 1.6 m/s2, and in the majority of elevators this would be an optimum value for acceleration to provide a good quality of elevator ride comfort. Acceleration above 1.8 m/s2 would often be perceived as objectionable.
From an analysis of four international elevator consultants ride comfort specifications for 1600 kg group of elevators at 4.0 m/sec in a common shaft the basic requirements were as detailed in table 1.
ISO 18 738 classifies noise, lateral quaking, acceleration and jerk as:
- Noise – Sound – a weighted sound pressure level in decibels.
- Lateral Quaking – A sideways acceleration measured in m-g.
- Acceleration – A rate of acceleration measured on the z-axis velocity and expressed in metres per second squared (m/s2).
- Jerk – The rate of change of z-axis acceleration, attribute to lift motion control and expressed in metres per second cubed (m/sec3).