Joerg Dieter Weigl

Design of rear wheel torque vectoring for dual motor Electric drive system

This paper is aimed at providing an insight into the torque vectoring concept which will be incorporated into the dual-motor drive system of the Electric Arc vehicle. The torque vectoring algorithm is based on Ackerman steering geometry and will become the basis of electronic differential which will vary the speed of the two rear driving wheels while cornering. The electronic differential acquires steering and vehicle speed data before computing the corresponding cornering response for each rear driving wheel using yaw rate prediction from the Ackerman steering geometry. Several series of Excel simulations were done to illustrate neutral steer, understeer and oversteer cornering cases for different cornering radius with varying vehicle speed and the cornering responses for each case was analyzed. This paper will also highlight how on-track testing of Electric Arc can verify the Excel simulation results and consequently determine tire cornering properties.

Converted battery-powered electric motorcycle and hydrogen fuel cell-powered electric motorcycle in South East Asia: Development and performance test

This paper presents the development and performance test of electric motorcycle in South East Asia i.e. in Singapore and Malaysia. National University of Singapore (NUS) team converted ICE based motorcycle (Honda CBR400) into battery electric motorcycle using lead acid battery pack and lithium polymer battery pack. Fuel Cell Vehicle Group in Universiti Teknologi Malaysia (UTM) built a fuel cell electric motorcycle which used hydrogen fuel cell system (named H2Motive® fuel cell motorcycle), lithium polymer battery pack and ultra-capacitor module. Road tests have been conducted to test the performance of both electric motorcycle types. Performance of H2Motive® fuel cell motorcycle was done by participating South African Solar Challenge 2008 in technology class. Results showed that H2Motive® fuel cell motorcycle was able to travel about 2400 km. Some roads were at steep and hilly climb and the motorcycle could stand during heavy rain. The converted CBR400 was tested in World Advanced Vehicle Expedition with 1600 km travel distance. NUS teams e-bike claimed third spot in that rally. Both type of electric vehicle performed well during the rally. It can be concluded that two of them were ready for gaining road-legal status.

Impact of Engineering Change in Design Education

It is common to carry out engineering changes during the design of new engineering products and systems. However, the impact of engineering change in design projects conducted in a tertiary education setting is not well understood.Such design projects are typically subjected to artificial design cycles as constrained by the academic calendar. The output of these design projects are also usually evaluated based on standardised assessment rubrics that may not consider the possibility of late engineering changes. As a result, students that arerequired to carry out extensive engineering changes during their design projects may be graded less favourably if their contribution prior to the changes are not systematically recognised.Their motivated level may be affected as well. In an attempt to improve the way design projects are carried out and assessed at tertiary education institutes, this paper discusses a pilot study that was put together to better understand the impact of engineering change in design education.

Fuel cell triple hybrid drive train for motorcycle

Motorcycles with electric drive are a clear advantage for cities, because of locally no emissions and driving with minimum noise pollution. This is especially known in South-East-Asian cities with strong motorcycle traffic [1]. But pure battery electric motorcycles have a significant range problem. This problem can be overcome with a hydrogen fuel cell hybrid system. Motorcycles in city driving have a very sharp load profile from extreme acceleration and sudden deceleration. To cater for this extreme load profile a triple hybrid systems with fuel cell, ultra capacitor and battery, have been developed and extensive tested. Tests of the triple hybrid system show a comparable acceleration and top speed performance in comparison to an battery - fuel cell only hybrid design. Additionally in the triple hybrid the load cycle energy on the hybrid battery can be reduced by 48% in exurban drive cycle test. An ultra capacitor - fuel cell hybrid only cannot provide the same performance as the triple hybrid or the battery - fuel cell hybrid.

To produce or convert: A case for large scale electric motorcycle conversion in Singapore

This paper explores the economic viability of the electrical conversion of motorcycles in Singapore. The vehicle market is regulated through Certificate of Entitlement (COE) 1 and road tax. These mechanisms do not cover converted electric motorcycles yet. Large-scale conversion allows for the production of 2500 motorcycles per year with an estimated workforce of 20 people. Electric motorcycles are cheaper to run compared to ICE motorcycles and these cost savings can recoup the price of the motorcycle in a short period. A policy innovation in this area could further spur large scale electric motorcycle conversion and make it a viable business.

Innovative Two Wheeler Technologies for Future Mobility Concepts

With the requirements of European Commissions White Book that demand emission-free city logistics in major urban areas until 2050, cargo bicycles may play a significant role for last mile deliveries. They require less space than vans and can be parked on the sidewalk. These electrically assisted bicycles, tricycles or quadracycles do not emit any local emissions and are capable to transport 50-250 kg of cargo. But, in topologically moved areas the capacity of conventional battery concepts constrains the transport range: delivery tours by bike can have a daily mileage up to 50-80 km. In the urge of finding energy carriers with a higher energy density than lithium-ion batteries hydrogen comes into the focus for innovative and sustainable cargo bike propulsion systems. This paper outlines the DLR activities to develop a versatile hydrogen fuel cell and its thermal management which suits the transport needs of commercial last mile deliveries with cargo bikes. First studies show that cargo cycles have high potentials not only in postal services but also for the growing courier and parcel service. Active thermal management systems to increase the range and the hill climb capability, the life time and the operational capability like shortening the refilling time are introduced in this paper.

Snowstorm—design and construction of an electric recreational flying machine

We propose the design of an electrical Vertical-Take-Off-and-Landing craft for recreational indoor use, based on established multi-copter controls. The indoor use case affords ultra-light design and a cost of a fraction of outdoor personal aircraft. We envision indoor flying parks that offer machines like Snowstorm to the general public. For this use case, advanced flight monitoring and automatic fail-over in case of operator mistakes will be desirable.

Test and development of efficient blades for use in VTOL aircraft

The Phoenix LR Type 2 mod 1system shows the necessity for further testing using a variety of set ups wth respect to blade and gears. Further, during the course of writing this report, numerous design changes to the blade to lighten the structure was developed which will help with the required performance of the rotor. By limiting the weight of the components, the blade would have to lift less weight and thus draw less power from the power supply to remain airborne. However, making a craft too light and sacrificing strength is also not advisable as well as there is a possibility of blade failure before the full lift capacity of the blade has been tested. These interplay of factors contribute to making the design of a high efficient long endurance aircraft an especially difficult task. This of course has not factored in the added complexity of balancing energy supply weight and airframe integrity. This balancing act is important as carrying more energy in the form of batteries increases the weight of the aircraft while requiring the blades to generate more lift. This added required lift again requires more energy to overcome the generated corresponding drag. Therefore, finding the most optimal layout and settings is crucial in this particular problem.

Performance simulation and testing of a converted electric lightweight sports car with differential drive concept

This paper aims to provide an insight into the performance of the electrified Caterham 7 that employs an electronic differential drive concept in its powertrain. Theoretically the performance being analysed is based on a quasistatic model developed for the car. The quasistatic model is a way to represent the powertrain components in equation forms and is more accurate than earlier developed static models. The theoretical data is obtained by simulating the quasistatic model with a specific drive cycle and analysis is on the energy consumption patterns, the range possible with a full charge on battery and look into how much it differs from the average operating point model. The performance of the car will also be simulated under different operating conditions to give a better idea on the cars theoretical operations. These simulations are primarily based in excel and will be valuable when the car is tested with a dynamometer. Apart from the simulation, the preparatory and miscellaneous works are also discussed in view of upcoming dynamometer tests. These works are mainly into the implementation of a comprehensive data acquisition system and power distribution unit. These systems together with the quasistatic model will provide a reference with which the actual driving and testing data from a dynamometer test can be compared with, enabling for better calibration of the model.

Environmental impact of converted electrical motorcycle

This study explores the environmental impact of the conversion of an internal combustion engine (ICE) sports motorcycle into a converted battery-powered electric vehicle (CBEV). Zero tailpipe emissions might lead to the assumption that such an ICE-to-BEV conversion will always yield net positive environmental benefits in life cycle greenhouse gas (GHG) emissions and energy reductions, but energy inputs and materials impacts associated with the conversion of a CBEV are weighed against savings during post-conversion usage. It was found that conversion would reduce the life cycle energy consumed and emissions produced of a typical motorcycle by 72% and 45% respectively. These findings have important considerations for the current global transportation landscape.