They aren't going away (hydraulic hybrids)

[IamIan]

Originally Posted by Old Mechanic

Ian, there are strong rational points of debate about in wheel and central locations for drives.

Originally Posted by Old Mechanic

The first vehicle I plan on building will be a tadpole trike with the rear wheel being powered. The drive could be connected to a separate wheel with a chain, like a motorcycle or be in the wheel itself. At this point I think I will build it separate since the losses through a chain are minimal and the fluid connections could be solid tubing with the drive fixed to the frame. It woud also allow the brake to be retained as a backup.

That has the potential to be a nice base platform to start with.

Are you planning on starting a build thread here for it when you get started?

Do you plan to retrofit or build from scratch?

[user removed]

I started a thread a few months ago. The machine shop I was working with is having problems finding the time to do the work. The owner is great, he just got hit with loosing a couple of key employees and has been working 7 days a week for several months.

It will be a scratch build. My brother just retired from a job welding at a local Navy weapons station. He has welded steel, aluminum, titanium, stainless. He even repaired compressor blades for the Naval Air Rewrok facility in Norfolk.

I already have the ball joint VW front axle, a harley transmission, and a 420 CC 9 HP Honda diesel engine with only a couple of hours on it. Going to make the front end fit a 71 VW super Beetle windshield. Tubular exoskeleton with hand hammered sheet metal panels welded between the tubing.

regards
mech

[nemo]

Any idea how much these hub motors would weigh in comparison to a standard drive assemblies? Too much unsprung weight might be a concern.

A good application for them would be in four wheel drive trucks, the ground clearance could be change from highway to off road to at will. This would eliminate the drive shafts and the associated u joint problems caused by raising the truck, but would require some thought as to how best to mount the hydraulic hoses.

[user removed]

Weight is about the same as the brake components it replaces. Durability should be great when you consider the two 4+ inch diameter bearings are rated for 6000 pounds each, since you have more force applied outward to the area of the lug nuts which will be much further away from the centerpoint than conventional, very similar to the older VWs and my 37 Ford, where the rim bolted to the outer edge of the brake drum.

The system would function 20 feet under water without issues.

When Virginia Tech looked at it they did not see reliability as any issue since the bearings would be capable of supporting the front wheels of a tractor trailer.

The accumulator adds weight to the vehicle, but that is more than offset by the elimination of the powertrain components from the flywheel to the drive axles. In a Nissan factory shop manual those components constitute 60% of the shop manuals reapir processes. In a Nissan Frontier 4wd truck the powertrain components are close to 1/3rd of the total vehicle weight. A HH system would weight far less than that.

Guys and gals, I have spent a lot of time trying to find the achillies heel of this system, and consulted with many people in engineeering and hydraulics. Watch a hand held hydraulic jack bend the frame of a diesel truck, powered by just your arm and hand and you understand the energy density of hydraulics.

The Kers systems have brought the advantages of short term high capacity energy storage. How much energy do you store in a pulse when hypermiling. Being able to travel about 1 mile on stored energy without any engine operation should cover MOST circumstances. In the scenario james offers, the best vehicle would be a Toyota Echo. Light, geared for climbing grades in higher gears, decent aero, with low sectional density that would mean less terminal velocity downhill.

There will always be a scenario where a hybrid will not offer any advantage.

Manufacturers are interested in the 99% not the 1% in volume production.

regards
Mech

[user removed]

http://www.youtube.com/user/Ride122609

This is a fixed displacement operational (on compressed air) prototype. The next step is in a vehicle. The concern of mine was would this be balanced in operation. You can see it is sitting on a frame machine in my friends body shop. My hand is holding the base. Not sure of the RPM but I would estimate it at 2k without a trace of vibration. If it could not be balanced then it would be useless as any in wheel drive.

regards
Mech

[jamesqf]

Originally Posted by Cobb

IAs I recall UPS had a delivery truck with this equipped for testing purposes? Cant say I ever seen a truck come to my house that was equipped with the system.

How would you know what's in the UPS truck that comes by your house? According to news reports The Pressure Is on as UPS Adds More Hydraulic Hybrids | Autopia | Wired.com they added another 40 or so in Baltimore & Atlanta last year.

[user removed]

I think the first UPS trucks were used around Detroit. Pretty sure they spend their lives in the same area as far as the local deliveries. I like following the UPS trucks that carry stuff between cities as well as the Wal Mart trucks. The drivers are very good and seem to be safetty oriented and not speed much. The HH UPS trucks are the ones used to deliver to your home or business and they are marked as HH trucks.

regards
Mech

[IamIan]

Originally Posted by Old Mechanic

Guys and gals, I have spent a lot of time trying to find the achillies heel of this system, and consulted with many people in engineeering and hydraulics.

I don't think there will be an 'Achilles heel' , kind of major flaw ... I suspect if designed and built right , it will perform mostly as anticipated ... including all the benefits you've listed.

The question I think will more fall into 2 major categories:

#1> How does the completed HH system end up comparing to other hybrid strategies ... Flywheel, Electric, etc... comparison will be on multiple fronts ... $, size, power density, energy density, durability, etc.

#2> What is the incremental improvement path for the HH vs other hybrid options.

- - - - - -

We will have to wait and see how the completed system turns out.

But no matter what ... .... good stuff.

[user removed]

The principle benefits I see in a HH vehicle is weight (overall) cost, simplicity and reliability.

Number one is cost. If no one can afford it then it fails before it is ever made. If any driver of reasonable means can afford it, then it will replace the worlds vehicle population in a decade.

An operational vehicle would improve in mileage from refinements in engines, aero, and rolling resistance. Specific design refinements in those areas would enhance efficiency overall. The EPA projected this in their 2006 research papers. Pic added below.

Reliability. According to the research by Va tech and the fact that many conventional parts no longer would exist, it would be reasonable to expect the powertrain to outlast the body structure. Engine longevity would also increase due to lower power on operational hours total. Engines would also not need any throttle contorl, just like a pressure washer pump, just sized for the application. Eevn much larger engines for climbing severe grades would still maintain high mileage levels since they wooul just have lower duty cycles. The INNAS design ran the IC engine only 11% when testing on the European cycle, compared to 100% in a conventional application.

Ease of service, each in wheel drive could easily be rebuilt, on the vehicle, in about 1 hour per wheel, compared to designs that have much more complex drivetrains. If one drive failed, for any reason, as long as it could still freewheel, then the vehicle could limp home on the other 3 wheels, or 2, or 1. Since the highest percentage of regeneration requires it at all wheels, all wheel drive owuld be the most practical application, but not essential, expecially if the driver is familiar with hypermiling.

I may have co mingled the two answers, but incremental improvements would be in accumulator construction and design, particularly if they could be incorporated into the vehicle structure itself. Current world cup racing sailboats use accumulators with 12k PSI pressure capabilities which would mean less weight and smaller displacement drives, with a multiplying effect as weight dropped overall and drives became smaller.

All improvements outside the drives themselves would immediately reduce fuel consumption. Sadly in current vehicles if you make the aero better, then the load and efficiency of the engine is also reduced. This design would have the opposite effect.

Va Tech did a lot of work looking at stresses and stress points. The found nothing significant which is the basis of the relaibility claim.

I think I have their final report on this cpu if you are interested. Its about 82 pages of information.

regards
Mech

[user removed]

I forgot this, cost of manufacturing, with about 25% fewer parts per vehicle once in production in mass then the cost to build would be significantly lower than even the cheapest conventional vehicle.

regards
Mech