Bendy/ DD
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Has any bendy bus/dd* got stuck before on the road ,what happen then?
*by trees.
Will the bendy bus break into two if it turns too much(i.e.The driver hold the steering to the extreme right/left and keep on going , won't it bend too much and the interconnecting will break)
OR
The bus keeps on reversing with the steering wheel straight with the 2nd carraige not parallel to the first carriage but bend.
I noticed that dd rear wheels turn a bit when the bus turns. Why is that so?
Are the both left&right rear wheels moving at the same speed when the bus(all sorts) turns? -
Originally posted by bus911:
no. if got height restriction there will be signalised warnings or overhead banners to inform the DD driver. as for bendies, a skillful driver can manoeurve most difficult city roads, jus like the bendy trial on 858 at changi airport ptb a few years ago.
Has any bendy bus/dd* got stuck before on the road ,what happen then?
*by trees.Will the bendy bus break into two if it turns too much(i.e.The driver hold the steering to the extreme right/left and keep on going , won't it bend too much and the interconnecting will break)
no, it won't break. or else lta wun allow it on singapore roads, let alone public bus service. they have done the engineering of the swivel connector throughly to pass the safety test.
OR
The bus keeps on reversing with the steering wheel straight with the 2nd carraige not parallel to the first carriage but bend.
as for the reversing part, it is possible but momentarily. to reverse bending to one side, u have to start reversing a bit to the opposite side before turning to where u wan to bend for a bendy bus. you can try to observe how 857 bendy buses reverse out of a 12m end-on berth at yishun interchange on weekends, but nowadays most buses vacate those lots except to pick up passengers so bendies can use the space of all 3 berths & dun have to drive all the way in (like boarding aircraft by walking over tarmac).I noticed that dd rear wheels turn a bit when the bus turns. Why is that so?
yes. tis is something like 4 wheel drive. by turning the rear wheel in the opposite direction, it reduces the turning radius of the bus. u have to imagine this one: the bus is turning left, the front axle wheels turn left, the rear axle wheels turn right a bit. tis is featured in the SBS 14.5m super long bus, articulated buses, and also the Transperth 1854 (Mercedes Benz O.500LE CNG bus) that came to singapore.Are the both left&right rear wheels moving at the same speed when the bus(all sorts) turns?
physics+maths question. no. for e.g. if the bus is turning left, the right wheel needs to cover a greater distance as it is further away from the imaginary pivot point (on the left flank in this case) where the bus turns along, and thus the corresponding radius & circumference is greater. now, since the time taken for both left & right wheel to manoeurve the turn is the same, speed on the right wheel, therefore, has to be greater.
if u have noted, in this case, that the left wheel moves very little at this time. u can imagine if it is an on-the-point turn, it seems as thought it is sliding to the other direction but not moving forward until the turning motion is over. -
I have noticed that when a VSO turns right, the bus will tilts very much to the left.
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that could either be:Originally posted by tranquilice:I have noticed that when a VSO turns right, the bus will tilts very much to the left.
1. suspension problem
2. the chassis is not heavy enough relative to the bodywork (which shld have been resolved even before the bus is delivered in mass production)
3. the bodywork is too heavy relative to the chassis.
a heavy chassis can help in providing a safety guard against collisions, but in physics, we have learnt that a heavy chassis lowers the centre of gravity of the bus (towards the chassis) so that it will not topple easily. tis is jus like how sports cars that race at high speeds have flat, low chassis to ensure the car does not topple easily under extreme conditions.
a typical SD without pax easily weights more than 9 tonnes. passengers are only allowed to fill up to slightly more than 6 tonnes more, which at the maximum capacity only represents at most 40% of the combined weight. -
The mechanics that allows this to happen is called limited slip differential.Originally posted by bus911:I noticed that dd rear wheels turn a bit when the bus turns. Why is that so?
Are the both left&right rear wheels moving at the same speed when the bus(all sorts) turns? -
Which wheels are the driven wheels?
Bendy(front, middle,rear)
dd(front,1st rear,2nd rear)
ordinary(front,back) -
Merc Bendy -> rearOriginally posted by bus911:Which wheels are the driven wheels?
Bendy(front, middle,rear)
dd(front,1st rear,2nd rear)
ordinary(front,back)
Volvo Bendy -> middle
VSO, VO, LO -> 2nd rear (absolute last)
Dennis -> 1st rear (middle)
Ordinary -> back -
Related, but a bit OT,
AFAIK, when O305Gs were first launched in Australia, public transport regulators were scared the trailer would jacknife and split from the main end. However, MB somehow managed to persuade the Aussies that wasn't the case, but to placate them no doors were placed in the trailer section, the only bendies in the world to only have doors in the front section. -
Bendies all have the jacknife buttons,The steering radius only end at about 60 degress compared to normal 12 m buses 90.
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What is jacknife?Originally posted by carbikebus:Bendies all have the jacknife buttons,The steering radius only end at about 60 degress compared to normal 12 m buses 90. -
Quoted from my dictionary: Fold against itself in accidental skidding movement.Originally posted by bus911:What is jacknife?
Understandable?
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What do u mean fold itself?Originally posted by tranquilice:Quoted from my dictionary: Fold against itself in accidental skidding movement.
Understandable? -
Fold against itself.Originally posted by bus911:What do u mean fold itself? -
When that happens it will form an inverted V shape, if I'm not mistaken.