Hydraulicspneumatics Com Sites Hydraulicspneumatics com Files Uploads Custom Inline Archive Www hydraulicspneumatics com Content Site200 Articles 07 01 2005 9803news0102png 00000003581

Real world challenge

July 26, 2005
Teams across the nation get closer to unveiling their designs for hydraulicpowered bicycle

There's nothing quite like a summer ride in the park, and several students are gearing up for a wild ride at the Cleveland Metroparks in Brecksville, Ohio, for the first-ever Parker Hannifin hydraulic bicycle competition.

Cal-Poly's bike utilizes regenerative braking to charge an accumulator.

Last September, Parker challenged its partner universities to come up with a useful and successful design of a human-and hydraulic-powered bicycle. Below are four of the nine designs student teams have developed.

Regenerative braking

At Cal Poly - San Luis Obispo, regenerative braking is the key technology the team is working on. Rather than applying brakes, this technique will use a break lever to operate a hydraulic motor. In turn, the hydraulic motor will charge an accumulator to provide energy.

The concept includes a pump or hydraulic cylinder that is hooked up to a crank. The cylinder pumps in both directions — when extending and extracting. The students also replaced the normal chain sprocket with a cam follower.

A piston pump will drive the hydraulic motor on the back of the bike, while the gear motor drives an internal 15-speed transmission for speed control.

Different teams, different styles

Murray State's computer-rendered bicycle features a simple hydrostatic system with hydraulic motor, pump, and accumulator.

Students at University of Illinois have created two teams, each working with the same hydraulic technology but with different bike styles — upright and recumbent. These teams are using a simple system that does not include an accumulator. The system will have a geared input to a pump in the front and a direct closed link to a motor in the back. The students created renderings of the bikes on ProEngineer and are using standard frames for the actual bikes.

University of California, Irvine's engineered schematic.

Sticking to the basics — Students at Murray State University are sticking to the basics with a simple hydraulic motor and pump. This system utilizes a hydraulic circuit, pump, accumulator, and gearing system. The rider will pedal the bike on the downhill, charging the accumulator for traveling uphill. This hydrostatic system will be fitted onto a three-wheel recumbent bike.

A pneumatic alternative — They're doing things a little differently at University of California, Irvine, where five students have opted to build a pneumatic-powered bike. Two 2-in. bore cylinders connected to the pedals generate pressure, while a 5-liter reinforced accumulator and 2.5 in. bore cylinder on the back turn the rear wheel. Solenoid valves, a microprocessor, and Hall-effect sensors were also included to time the air supply to the rear piston so the bike will move forward. A rear rack holds the bike's pistons, plumbing, and accumulator. The students chose a pneumatic system because it will keep the bike lighter than with a hydraulic systems, and it is environmentally friendly.

Continue Reading

Handbook Simplifies Advanced Aspects of Mobile Hydraulic Controls

May 10, 2017
Author Brendan Casey lays out his hydraulics know-how that he acquired over 27 years in a simple handbook made for people that want to improve their skills in troubleshooting ...

Kidney loops: They aren't just for hydraulics any more

Sept. 1, 2004
When was the last time you changed the oil in your refrigerator's compressor? That was a question posed to me by Ken Stofen of Racine, Wis. The answer, of course, is never, and...

Sponsored Recommendations


May 15, 2024
Production equipment is expensive and needs to be protected against input abnormalities such as voltage, current, frequency, and phase to stay online and in operation for the ...

All-In-One DC-UPS Power Solutions

March 13, 2024
Introducing the All-In-One DC-UPS, a versatile solution combining multiple functionalities in a single device. Serving as a power supply, battery charger, battery care module,...

Motor Disconnect Switches

March 13, 2024
With experienced Product Engineers and Customer Service personnel, Altech provides solutions to your most pressing application challenges. All with one thought in mind - to ensure...

DC Power Solutions: Streamlined Power Supplies for Every Need

March 13, 2024
CBI All In One UPS Power Solutions combine the requirements for several applications in just one device which can be used as power supply unit, battery charger, battery care module...