Comments on: Parker Hannifin Chainless Challenge

By: Robin Aurelius

Robin Aurelius — Sat, 01 Jun 2013 18:38:34 +0000

I saw one from Germany in various sizes, looked good for what you suggest. The hydraulics could add extra weight to get better traction up front where needed on hills, or loose gravel and dirt. I am going to build one.
Robin Aurelius
916-531-4110
raureli@yahoo.com

By: Anna

Anna — Sun, 14 Oct 2012 11:18:24 +0000

another potential advantage is for recumbent bicycles or trikes which could benefit from front wheel drive. The reason to consider FWD for this style of bikes is that the traditional rear wheel drive configuration requires a very long drive-train involving long chains and idlers. Hydraulic drives would eliminate many of the problems of chain driven FWDs.

By: Anonymous

Anonymous — Wed, 30 Jul 2008 20:54:00 +0000

The other potential that hasn’t been mentioned in the blog is the potential for regenetive braking. By incorporating both the “efficiency” benefit that HeavyT mentions, regen braking offers further advantages and potentially makes daily work commuting with a bycicle over greater distance even more possible

By: bikesgonewild

bikesgonewild — Wed, 30 Jul 2008 04:31:00 +0000

...heavyt...yes, thank you for the input...

...there is an "efficient" mechanical advantage to adding a hydraulic system...cool...

...so, talking of bicycles & the additional weight of a hydraulic assist, i'm now wondering if there's any type of comparative efficiency in relation to electric-assist bikes, which are also heavier...& that would be before factoring in the need to generate said electricity...

...not tryin' to drive anybody crazy w/ this but definitely curious...

By: heavyt

heavyt — Tue, 29 Jul 2008 00:24:00 +0000

This is an excercise in efficiency. In a traditional hydraulic system the bike rider is acting as the prime mover, an electric motor or gas engine, used to power the hydraulic system. Based on a given power input there is a variety of speed and power combinations available. All of which are fixed by the input. In a traditional system the motor speed does not change, and this is where the fun starts. With a hydraulically powered bike, the rider can constantly charge the hydraulic system at a fixed, “efficient” rate, while getting a variety of output combinations. This type of testing is being done now on a larger scale with heavy trucks that are hydraulically driven. Imagine being able to keep your car engine at a low RPM, maybe just above idle, but having the capability of normal speeds, acceleration, and power, all without burning no more gas than if you were sitting at idle. the hydraulic system allows this to be possible.
I hope this provides some insight.

By: James

James — Mon, 28 Jul 2008 12:53:00 +0000

bikesgonewild, sorry I misinterpreted your comment the first time around (that is what happens when I skim through the comments quickly). Now that I understand what you were asking, all I can say is; good question- I don’t know. It is probably over my head, but I would love to hear someone else speculate on that. Any takers? Ron, jimmythefly, maybe someone from Parker Hannifin; can any of you address bgw’s questions?

By: bikesgonewild

bikesgonewild — Mon, 28 Jul 2008 07:06:00 +0000

...will & james...you gentlemen aren't "getting" my query...that or perhaps i'm not expressing myself clearly...

...& first off, i think i grok the nature of the competition...pretty fundamental "expanding horizons" school stuff, i imagine...

...anyway, lemme try again...i'm wondering, considering the efficiency of a bicycle drive train, if there is any 'increased &/or beneficial' mechanical advantage to using a pedal powered hydraulic system over a simple 'direct' pedal powered system ???...
...when powering something along the lines of, say, the 'maya-project' water pump or the welding rig you featured awhile back...

...or is that adding a third step to what might be better as a two step system ???...

By: jimmythefly

jimmythefly — Fri, 25 Jul 2008 20:50:00 +0000

To add to what James said, excercises with human-powered vehicles puts focus on effeciency that could be overshadowed if this was a motorized project. The solution can’t just be “get a bigger motor”. The relative cost and complexity of the supporting vehicle makes bicycles an attractive platform, too. (though in addition to what I mentioned above, I saw two different bikes with Rohloff hubs in the photo set).

By: James

James — Fri, 25 Jul 2008 15:17:00 +0000

BGW, Will, and Garrett, I could be wrong, but I see this competition as more of an exercise in hydraulics engineering for other applications than as an attempt to actually make an alternative drive bicycle (I probably should have pointed out in the post that Parker is involved in alternative energy projects including high performance electric scooters, wind and ocean wave energy generation, and hydraulic hybrid energy recovery vehicles). I think that the bicycle project/ race just gives the students a way to showcase their thought processes in solving a problem with a clearly defined set of constraints.

When I was in school, we had to make a functional chair using the material from a single piece of cardboard. The goal was not to make a real product but to learn to be creative in solving problems with seemingly difficult constraints. I kind of see the chainless challenge as the same kind of exercise (on a bigger scale). Again though, I hope someone from Parker Hannifin can correct me if I am misinterpreting the intent of the project.

By: Garrett

Garrett — Fri, 25 Jul 2008 15:08:00 +0000

I’m sure there are many innovative ideas presented in this challenge, but I fail to understand its purpose. Unless you need to drive both wheels, I think hydraulic power just makes things more difficult.