Schriftenreihe .;technologiekompetenz Verkehr in

A3-PROJECTS
A3 | A3 – Austrian Advanced Automotive Technology | A3 – 4 th Call (2006)
HYPERBIKE
Hybrid pedal-assisted recuperating bicycle
The HyperBike study (hybrid pedal assisted recuperating bicycle) takes up a subject The HyperBike study investigated assisting
which has been practically forgotten due to the low performance capabilities of earlier the cyclist inconspicuously using an electric
secondary battery types: assisting the cyclist by using an electric drive, without adding powertrain. Given the further development in
significant weight. The further development in both short-term electric storage electric short-term storage units, this subject
(double-layer capacitors, high-current capability lithium polymer ion secondary has become relevant again. In addition to this,
batteries) and in propulsion systems (e.g. permanent-magnet synchronous motors, the possible range is said to be increased
dual-rotor machines with axial gap, etc.) offers an opportunity to rethink the technology significantly through energy regeneration.
and/or the principle. Possible applications scenarios for this
technology in the automotive sector are being
The study looked at concepts going far beyond current technological know-how, and analysed.
applied the principle for regeneration of braking energy typical of hybrid vehicles to
very small-sized energy storage units for a light two-wheeler: using these light shortterm
storage units means that the weight disadvantage of existing electric drive
solutions can be alleviated, whilst also significantly improving range by using highefficiency
recuperation, especially in urban areas with stop & go-type operation.
The specific aims of the HyperBike project were:
> Increasing comfort in stop & go traffic (acceleration without heavy pedalling)
> No significant additional weight (i.e. can also be ridden without the auxiliary drive in
operation)
> Similar to a standard bicycle (no visible ballast, modern design)
> Long service life, typical of bicycles, for all components
Optional practical functions include:
> Integrated ABS (anti-blocking system on the drive axle)
> Integrated LED daylight driving light (safety aspect)
> Safe braking without wear (no influence from wet brake blocks)
Given that both the target unit weight and the high-efficiency recuperation drive system are completely new territory, the feasibility
of the concept needed to be examined. In the study, this is to be achieved in part by using a simulation of the energy flows, and in
part by examining the innovative, light, electrical machine for overload capacity and cooling with regard to costs.
Looking at the flow of inner-urban transport, the conclusion is reached that there are potential savings of around 1 / 3 of the total
energy used if the brake energy is regenerated in stop & go traffic. Many locally-operating fleets are operated with low maximum
speeds and with frequent braking and acceleration. This includes two-wheeled vehicles (delivery vehicles), light vehicles (courier,
express and parcel delivery services) and also heavy utility vehicles (waste collection and recycling vehicles), as well as rail-based
transport (tram-cars).
Assessing the areas of application for the stop & go system indicated the following
favourite applications:
> Inner-company transport (between buildings)
> Shopping/socialising
> Assisted mobility
> Linking to public transport (Bike&Ride, public bikes)
> Warehouse / indoor transport
> Vehicles for printed media and postal distribution services
> Powered vehicles for room cleaning
Project management:
Austrian Mobility Research –
FGM – AMOR gemeinnützige
GmbH
Project partners:
University of Leoben – Institute
for Electrical Engineering,
DanklHampel Design
Simulating stop & go operation using super-capacitors as energy storage has suggested a potential saving of at least 15%. The key
factors are high-efficiency regeneration and low resistance when the regenerated energy has been spent. Optimising the electric
drive resulted in a reduction in active mass of 25% compared to state-of-the-art machines. The market assessment indicated an
initial market size of 37,500 bicycles with the stop & go system integrated. The potential has been evaluated at 450,000 units per
year for Europe. Migrating of the stop & go technology into other pedal-assisted vehicle segments with a similar power demand is
likely. Furthermore an application involving hand-guided units – such as hospital beds, trolleys etc. – is expected. The technological
findings may be transferred to the automotive sector, bringing efficiency improvements.
51