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(...) It does, however, get more complicated that than - see a recent thread on lugnet.technic discussing this: (URL) would have flagged it up to you before, but the thread did not deal with the issue of powering the axles, only steering. (...) (24 years ago, 13-Dec-00, to lugnet.robotics)
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thanks jennifer, those threads help some, but i have put the whole idea behind me for the present and started working on the phased walking mechanism for the december challenge actually now that i saw more of the printout those writings helped lots (...) (24 years ago, 14-Dec-00, to lugnet.robotics)
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(...) Heh! I've come to the conclusion that while it is interesting to tinker with suspensions, it is better to use the space in the models for other things. After all, the suspension one can make in a LEGO model is nowhere near realistic in it's (...) (24 years ago, 14-Dec-00, to lugnet.robotics)
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(...) ... A number of cars have done this in the past, though not many were brought to the US. Amusingly enough, a little-known option on the 240SX (I forget which years) is the HICAS (HIgh CApacity Steering) system which is a 4WS option. The rear (...) (24 years ago, 14-Dec-00, to lugnet.robotics)
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(...) If you are parallel and very close to an obstacle, like a curb or a wall, you can't get away from it with all-wheel steering. As soon as you turn the wheel to get the front away from the wall, the back of the vehicle will smash into it. This (...) (24 years ago, 14-Dec-00, to lugnet.robotics)
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(...) Thanks for that explanation, everything is much clearer now. I suppose it is to do with the line perpendicular to the vehicle coinciding with the centre point of the turning circle; with all wheel equal steering, it will intersect the middle (...) (24 years ago, 14-Dec-00, to lugnet.robotics)
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(...) Yes, I agree here. I suspect much of it has to do with the weight and balance of a Technic model, which is going to be vastly different, even in scale terms, from a real vehicle. Saying that, the suspension on the 8448 seems pretty realistic, (...) (24 years ago, 15-Dec-00, to lugnet.robotics)
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Another problem with all wheel steering is the problem of "switch over." Honda had a prototype of an all wheel steering car which used the mechanism of turning the wheels in opposite directions at slow speeds for improved turning radius and turning (...) (24 years ago, 15-Dec-00, to lugnet.robotics)
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(...) Many kinds of construction equpiment actually use unsprung suspensions, so I think this is a sane approach. A telescopic handler, for example, needs to be able to lift many different kinds of weights, hence it cannot have the kind of (...) (24 years ago, 17-Dec-00, to lugnet.robotics)
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(...) Indeed - I've seen a good variation of this with a 4 axled vehicle which had two bogies with two axles each. Each pair of wheels on the side of each bogie had longitudinal pendulum type unsprung suspension, and the front bogie had an (...) (24 years ago, 18-Dec-00, to lugnet.robotics)
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(...) For our purposes, this may not matter. However, couldn't the rear wheels be steered with a reciprocator? So as the steering wheel turns to the right, the rear wheels start turning right, then turn back to the left? So at, say 1/4 turn, the (...) (24 years ago, 18-Dec-00, to lugnet.robotics)
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