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Been doing two sets of tests recently. I'm currently in Millbrook, one of the big proving grounds in England, staring through a window at a London double decker bus sitting on a proper big dynamometer (bit like a treadmill for exercising your car the lazy way).
The bus is finally getting a nice big, fat single digit mpg figure, slightly higher than a Ferrari but slightly lower than a Range Rover. Which we're pretty pleased with, considering it's 14 tonnes and loaded to represent 60 passengers.
In a hybrid like this, the wheels are driven by an electric motor, which is fed by a battery and/or diesel generator. Ours uses a 2.4 litre ford engine - the same one as the Transit van or Land Rover TD5, along with a wardrobe full of lithium ion batteries. The efficiency gain comes from two places: Firstly when the vehicle brakes, instead of simply throwing the energy away through friction brake pads (the usual way), the motor acts as a generator, recovering the energy to recharges the batteries. Secondly the engine usage may be dislocated from the vehicle's current operation - the engine speed doesn't need to be related to vehicle speed, but can constantly operate at a range of sweet, efficient spots (or turn off altogether when it's not needed).
The second set of tests I've been running are slightly less technical:
I've hacked together a circuit on a breadboard to allow manual over-riding of the automatic gearbox in our lovely, but sadly automatic, Hilux. Combined with a volume changing paddle off an old Renault Laguna, a very nervous Louise and myself managed to drive to the baker at the weekend with probably the only tiptronic Hilux Surf in the UK.
There's a few features that I'm pretty pleased with, including a big, clunky switch that makes a solid, reliable 'clunk' when you change between auto and manual. Oh, and a 7-segment display to tell you what gear you're in (top left in the image), synchronising between the auto and manual gear selection when changing between them or starting the vehicle, and automatic dropping to first gear when the vehicle stops, even when in manual. And lots of relays that click satisfyingly to let you know something's happening.
After a bit more testing, this will hopefully become a permanent feature. If I understand the potential benefits correctly (unlikely, but hey, I can dream) then it may be able to improve fuel efficiency by 5-10%, along side looking cool.
Which will make it use a mere 1/3 of the fuel per mile of the bus currently vibrating the floor.
Jon - indeed. I accidentally bought 200 PNP transistors instead of NPN, and couldn't work out how not to destroy them. So there's a good 20 in the bin, but I got there in the end...! By the way, you visiting Ireland soon?
And Russell, I've kindly taken out your extra spaces, but will need to get round to fixing that. And you can be sure that if cameras weren't banned in the whole of Millbrook... (there's all sorts of interesting things you're not allowed to take pictures of). And what's wrong with my midwifery? I'll have you know I've been lambing sheep again, it can't be that different? And I'm going to do my best to solder together a prototype tomorrow morning (after flying back to Belfast, before getting the ferry to Scotland), so you'll hopefully see it at the weekend.
P.P.S. Does the bus take off on the treadmill?
P.P.P.S. Even despite all this, I suspect your engineering still manages to better your midwifery.
P.P.P.P.S. Why do I need to update the spam-checker before previewing what I've written, and why, when I preview and then post, does it create such enormous (double? triple?) line breaks?
I always suspected it, but this confirms.
When can I have a shot?
does the tip-tronic aspect of it have to pass MOT, etc?