Betajet- While in bed last night (get a life) I think I solved the problem of the flying pickup arms of the trolley bus and removed the need for poles (wooden) and Muni-men; while at the same time providing some sales for the semiconductor industry. Why not have a twin pantograph structure with two curved contact bars separated with a diode. The curve of the bars arranged so that if one of the overhead wires reached the position where it was touching both pantograph loops contact was lost with the other overhead, also put a diode in series with each pantograph branch. It would certainly work for DC and and AC version could be worked out. Sorry forgot to put the central diode in original posting.
Other few concerns are what's the impact of megnatic field on things around? How strong is megnatic field and will it hurt people with pacemaker or wearning metals? Also is it possible that I carry a coil and steal enery to charge the device I have.
Induction chanrging was not very succesful in mobile industry for charging devices, not sure if it will work effectively on road.
Ron: The only time MUNI needs ground staff is when they deliberately route a bus down a block where there's no overhead wires. I've only seen this done once. I assume this is because of street repairs, overhead wire repairs, or temporary traffic re-routing. The driver takes care of unplanned disconnects.
Efficiency Efficiency-Why go to the bother of generating power feeding it to the induction coils frquency converter, magnetically induce the power to the bus charge the battery then run the motor to drive the bus. When with overhead cables trolly buses, trams, trains can use the generated power fed straight to the vehicle.
Does the word efficiency ever enter the minds of these people? Perhaps somebody would do an efficiency comparison calculation.
Betajet; I can remember trollybuses in the UK that when the electric pickup poles disconnected from the overhead wires the driver would draw a long wooden pole from beneath the bus and reconnect. No extra ground staff needed!
They still use electric trolley buses in San Francisco, as well as 300 other cities worldwide according to Wikipedia. The San Francisco buses now have a small amount of battery power so you don't lose the lights if you lose contact, and also so that buses can go short distances untethered if a street gets blocked or a route changes and they haven't had time to put up new wires. (MUNI does need to have ground staff to lower and raise the poles in that case.)
I love the trolley buses -- so quiet and smooth, with no fumes.
What the heck, guys. When I was little, there were public buses running all throughout Rome that were powered by overhead cables. No, it wasn't induction, it was direct contact. Still, the scheme is rather limiting, but there's no problem of energy starvation that battery-powered solutions create.
Occasionally, a driver would steer too far from the cables, and snap-crackle-pop, the contact arms would break free of the cables. Then he'd have to get out and hope to be able to reconnect them and steer back where he belonged.
The other thing is, I had a meccano set in those days, sort of like the US erector sets. I had both a battery electric motor and a plug-in electric motor. Even for moving vehicles, I ended up wanting to use the plug-in motor with a long extension cord. Way, way more power available. I'm sure that experience did a lot to make me skeptical of most of these battery-powered electric ideas.
if any system could be modified to actually use this kind of thing, it seems like mass transit would be the best fit. The bus systems already have small sections of road (bus stops and stations) that are pretty much only for them.
A Book For All Reasons Bernard Cole1 Comment Robert Oshana's recent book "Software Engineering for Embedded Systems (Newnes/Elsevier)," written and edited with Mark Kraeling, is a 'book for all reasons.' At almost 1,200 pages, it ...