The multi-speed drive hub mainly makes for change speed with planetary gear trains. It has some advantages such as small, change the shelf steadily to move and difficult to receive external environmental impact. So the multi-speed drive hub has already become the focal point that every bicycle's factory researches and develops gradually. The purpose of this work is to develop a system methodology for the computer-aided design of multi-speed bicycle drive hubs. First, analyzing multi-speed drive hub patents to identify the basic characteristics and requirement of multi-speed drive hub, and using a systematized method synthesizes the feasible gear trains. Second, a method is proposed to determine the feasible multi-speed sequence tables for each planetary gear train. Third, a method is formulated to find the gear ratios and gear teeth according to the feasible multi-speed sequence tables. Fourth, a method is to design and dispose the governors of multi-speed drive hubs easily. Finally, using Visual Basic 6.0 procedure language develop a computer software easy to use by utilizing the above-mentioned procedures, and the results of this work will be benefit to the development and design of multi-speed bicycle drive hubs.

A multi-speed drive hub is one of important components in transmission system. The purpose of this work is to develop a system methodology for the design of multi-speed bicycle drive hubs. First, analyse multi-speed drive hub patents to identify the basic characteristics and design requirement of multi-speed drive hub. Second, using a systematized mathod to synthesize the feasible gear trains. Third, a method is proposed to determine the feasible multi-speed sequence tables for each gear train. Fourth, an analytic method is formulated to synthesize the gear ratios and gear teeth according to a set of desired speed ratios. Fifth, design and dispose governors of multi-speed drive hubs. The results of this work will be benefit to the development and design of multi-speed bicycle drive hubs.

The wheelchair is an auxiliary tool for people who have defective legs. In comparison with the power wheelchair, the manual wheelchair has the advantage of low price and easy carrying. The regular, standard manual wheelchair is only suitable for residential environment and short-distance movement, and it¡¦s unsuitable for outdoor recreation and long-distance movement. The purpose of this study is to develop the manual wheelchair for outdoor recreation and long-distance movement, so that the users can expand their living space beyond the residential areas. In order to enhance the efficiency of propulsion for manual wheelchairs, a systematic designing method for propulsive mechanisms is proposed in this study in which the propulsive way of the traditional manual wheelchair is replaced by propelling the propulsive mechanism. In order to let the wheelchair be adapted to all kinds of environments, the multi-speed drive hub is applied to the manual wheelchair to enhance the users¡¦ force with more flexibility. In addition, this study also designs and manufactures a wheelchair to test the functions. The results of the test are then recorded and examined to provide the references for the future design.

­^¤åºK­n A multi-speed drive hub is one of important components in transmission system. The purpose of this work is to develop a system methodology for the design of multi-speed bicycle drive hubs by using a concept of combination. First, identify the basic characteristics and design requirement of combinative multi-speed drive hub. Second, using three combinative the useful gear trains. Third, a method is proposed to determine the feasible multi-speed sequence tables for each gear train. Fourth, an analytic method is formulated to synthesize the gear ratios and gear teeth according to a set of desired speed ratios. Fifth, a computer programs developed for the automatic analysis the transmission performance of drive hubs. The results of this work will be benefit to the development and design of multi-speed bicycle drive hubs.

A multi-speed drive hub is one of important components in transmission system. The purpose of this work is to develop a system methodology for the design of multi-speed bicycle drive hubs. First, identify the basic characteristics and design requirement of multi-speed drive hub. Second, using the useful gear trains. Third, a method is proposed to determine the feasible multi-speed sequence tables for each gear train. Fourth, an analytic method is formulated to synthesize the gear ratios and gear teeth according to a set of desired speed ratios. Fifth, the basic theory for transmission analysis of multi-speed drive hubs will be developed. The results of this work will be benefit to the development and design of multi-speed bicycle drive hubs.

The planetary gear train are applied in multi-speed drive hubs for bicycles. Since a multi-speed drive hub has the advantages of the small volume and stable gear shifting, it is used widely in folding bicycles and electric bicycles. The distributed-flow-type multi-speed hubs could provide more gears, the related design theory is not well development. Thus, the purpose of this research is to develop a systematical methodology for the design of the distributed-flow-type multi-speed hub for bicycles. First, an existing patent is analyzed to identify the basic characteristics and the requirements of the multi-speed hubs. Based on the basic characteristics and the requirements, a systematical procedure is proposed to synthesize the feasible concepts of the planetary gear trains. Second, another procedure is proposed to determine the feasible clutching sequence tables. Third, the difference in value of the angular velocity is assigned to calculate the gear ratio and to determine the numbers of the teeth of all gears. Finally, the shifting-gear system in the multi-speed drive hubs is designed and arranged. The evaluation of the multi-speed drive hubs is proceeded to select the better alternatives. The result of this work obtains twenty-senven types of the distributed-flow multi-speed hubs for bicycles, three of them could reach sixteen speeds.

Advances in electro-mechanical actuation have encouraged revolutions in automobile design which promise to increase fuel efficiency, reduce costs, improve safety and performance, and allow a wider range of architectural choices for the vehicle designer and manufacturer. This is facilitated by the concept of an intelligent corner (IC). The IC consists of traction, steering, camber, and suspension actuators working together to control the forces generated at the wheel/surface interface, allowing complete control of vehicle motion with completely active, as opposed to passive, systems. The most critical actuator to the longitudinal performance of an IC vehicle is the traction system, envisioned in this case as a hub mounted electro-mechanical actuator connected directly to the wheel. This traction actuator consists of a number of primary and supplementary components, including a prime mover, gear train, clutch, brake, bearings, seals, shafts, housing, etc. The consideration of these components in the design of an in-hub electric drive actuator is the subject of this report. Currently, gear trains are used in automobiles to match the operating speed of an internal combustion engine (ICE) to the speed of the vehicle on the road. The same need is anticipated for the hub drive wheel, although with fewer reduction ratio choices due to the responsiveness of the electric motor. Specifying a gear train design includes selecting a gear train architecture, and designing the gears to handle the expected loads. A review of gear design and gear train architectures is presented. A number of electric machines are used in industrial, and now more commonly, vehicle applications; of these, the switched reluctance motor (SRM) represents an excellent candidate for a vehicle prime mover due to its ruggedness, broad torque speed curve, low cost, and simplicity. Integrating the motor and gear train into an electro-mechanical actuator with multiple speeds requires consideration of other ancillary components. Brief design guides are presented for clutches, brakes, bearings, seals, and the structure for the in-hub wheel drive. Given the analytical descriptions of the drive wheel components, methods for managing the numerous design parameters are developed and expanded. Actuator specifications are chosen based upon meeting various vehicle performance requirements such as maximum speed, gradeability, acceleration, and drawbar pull. A proposed parametric drive wheel design is presented to meet the requirements of a generic heavy vehicle. The design demonstrates the feasibility of actuator technology that can be used to increase the performance, maintainability, and refreshability of hybrid electric vehicles while allowing open architecture paradigms to lower costs and spur new levels of manufacturing and innovation. / text

This thesis aims to design and develop LSPM motors capable of operating in two distant synchronous speeds with good starting torque and steady state characteristics for variety of industrial applications, in particular offshore and maritime applications. The proposed designs are based on variable pole numbers for the stator and the rotor. The stator winding consist of two independent windings with different pole numbers to switch the winding and change the operating pole count for low and high speed applications. For the motor to operate in these two distinct operating speeds, the rotor must be capable of creating two different magnetic polarities (pole numbers) to adapt itself to the stator operating pole number. For this purpose, two different schemes for the rotor structure are proposed. In scheme I two-speed operation is realized by the combination of electromagnetic torque and reluctance torque which enables the motor to operate as a synchronous PM motor at high speed and synchronous reluctance motor at low speed. In scheme II, rotor with dual PM polarity is proposed which enables the motor to operate as a PM motor at both low and high speed regions.

Pavements in Canada that are built on top of frost susceptible soil experience loss of support in early spring as the frozen structure begins thawing. To minimize pavement damage, low- volume roads rely on Spring Load Restrictions (SLR), since building these roads to withstand spring thaw is usually not feasible. However, implementing SLR increases operational costs to commercial transporters and impacts local economies. The Ministry of Transportation Ontario (MTO) is routinely faced with requests from the truck industry to lift restrictions on certain roads, and questioning from municipalities that seek understanding on the needs for SLR in their roads. To help answer these questions, a comprehensive study was performed at 15 Seasonal Load Adjustment (SLA) stations across Ontario. The data collected included Falling Weight Deflectometer (FWD) testing, borehole investigation, climatic data, traffic volumes, and pavement rehabilitation data. A backcalculation using the FWD data estimated pavement structural capacity and remaining service life for each SLA for different dates throughout spring, followed by a life cycle analysis using the rehabilitation data. The SLAs were divided in three groups of similar pavement support conditions based on the service life analysis results. Results indicate that none of Group 1 SLAs need load restrictions, with the calculated remaining service life being greater than 25 years for all test dates. Within Group 2, pavement recovery throughout spring suggests that SLR could extend service life, although generally not necessary for the intended life cycle. Results indicate most SLAs in Group 2 achieving a full life cycle from the last rehabilitation activities for estimates based on early spring parameters, suggesting that these roads were likely designed with spring conditions accounted for. For Group 3, the lack of structural support and low service life values indicate the need for strict load restrictions to avoid excessive damage and maintain serviceability. Pavements with high-quality subgrades, granular structures and non-frost susceptible materials, thick asphalt layers and major rehabilitation activities were found to generally perform well for spring conditions. However, with several site-specific conditions, an overall recommendation for implementation of SLR cannot be generalized based on the pavement structure and subgrade soil type alone. The structural condition and thawing behaviour of individual sites must be thoroughly understood before a decision is made, as investigation might indicate that some roads can withstand full traffic year-round and would not need SLR, while others might need more rigorous restrictions. In addition to the service life analysis, approximately 600 lane km of deflection data was collected using a Multi-Speed Deflectometer in Southern Ontario. Recommendations were made for potential applications of the equipment as a network screening device, able to identify weak road sections in a time and cost-effective manner prior to a detailed investigation using FWD; and for regular monitoring of road conditions at a network level, including the monitoring of seasonal variations. / Thesis / Master of Applied Science (MASc)

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Conventional electrical vehicles (EVs) favour mostly permanent magnet machines with single speed gearboxes. This is understandable, the PM machine has a high power density making the electrical machine smaller in size. The PM machine also has a favourable field weakening capability combining this with a single speed gearbox nearly perfectly matches the required traction curve. However the dependency of rare earth metals from China and the environmental issues raised by mining these metals raise concern. Therefore alternatives should be considered. Induction -, switch reluctance - and wound rotor machines are all gaining ground as favourable traction machines to power vehicles. The reluctance synchronous machine (RSM) is known for it’s robustness and high efficiency, however the machine has a limited field-weakening capability. To overcome this short coming a multi gearbox from an internal combustion engine (ICE) is suggested. By combining the RSM and multi speed gearbox it is possible to match the traction curve. There are numerous advantages offered by using this system, especially from an performance and efficiency point of view. However there are also numerous challenges faced by using the suggested powertrain, however the focus of this study is mainly on performance and efficiency of the motor and the powertrain. As a case study a Corsa 140i is used and the design specifications is taken from the ICE. The aim is to design a RSM that meets the specifications of the ICE. The RSM structure is mathematically modelled then optimized using commercial optimization and 2D finite element software. To evaluate the design of the RSM, the motor is then tested. The powertrain is then tested by connecting the motor onto the gearbox of the Corsa and the efficiency of the powertrain is evaluated. The test results it shown that the RSM can be used as a traction motor. There are two motors built one with NO20 and the other with M530-65A lamination steel. Both motors perform well throughout the speed and torque spectrum. The measured efficiency at the rated condition for the motor with the NO20 steel is above 91% and the motor with the M530-65A laminations above 89%. The power train is is tested in 4th and 5th gear. The efficiency of 4th and 5th gear is approximated and the efficiency is above 90% . This high efficiency makes the multi speed gearbox a competitor for the EV power train. / AFRIKAANSE OPSOMMING: Elektrisie voertuie (EVe) het meestal permanent magneet motors met ’n enkel spoed ratkas. Dit is verstaanbaar, die PMS masjien het ’n hoë krag digtigheid wat die masjien kleiner maak in grote. Die PMS masjien het ’n baie goeie vloed veld verswakkings gebied en as dit gekombineer word met ’n enkel spoed ratkas, volg dit die velangde traksie kurwe amper perfek. Die nadeel is dat die PMS motor skaars aard metale nodig het vir die magnete van China af. Die probleem is dat daar baie omgewings probleme gepaard gaan om die metale te myn en China beheer die mark. As gevolg hiervan moet ander tipe motors oorweeg word as traksie motors vir voertuie. Skakel reluktansie, induksie en ’n wikkel rotor motors is almal besig om vordering te maak as traksie motors vir EV’e. Die sinchroon reluktansie motor (RSM) is bekend as ’n robuuste en effektiewe motor. Die probleem met die RSM is dat dit nie ’n goeie vloed veld verswakkings gebied het nie. Om die probleem te oorkom, word ’n veranderlike spoed ratkas van ’n binnebrand engin voorgestel. Deur om die RSM en die veranderlike spoed ratkas as ’n dryfstelsel te gebruik kan die verlangde traksie kurwe ook verkry word. Daar is talle voordele om ’n veranderlike spoed ratkas te gebruik, veral van af ’n draaimoment verrigting en effektiwiteits oogpunt. Daar is ongelukkig ook baie uitdagings wat gepaard gaan as ’n veranderlike spoed ratkas gebruik wil word in die dryfstelsel. Alhoewel daar baie uitdagings is kyk die studie slegs na die draaimoment verrigting en die effektiwiteit van die dryfstelsel. ’n Corsa 140i word as ’n gevallestudie gebruik en die spesifikasies vir die elektrisie motor word vanaf die spesifikasies van die binnebrand engin geneem. Die doel is om ’n motor te ontwerp wat dieselfde spesifikasies het as die binnebrand engin. Die RSM strukstuur word wiskundig gemodelleer en dan geoptimeer deur gebruik te maak van kommersiele optimering en 2D eindige element sagteware. Om die ontwerp te verifieer word die motor getoets. Die dryfstelsel word dan getoets deur om die motor met die raktas te konnekteer. Die draaimoment verrigting en die effektiwiteit word dan ge-evalueer. Twee motors word gebou, een met NO20 laminasies en een met M530-65A laminasies. Beide motors het goeie verrigting deur die spoed en draaimoment gebied. Die gemeete effektiwiteit van die motor met die NO20 laminasies is bo 91% en die motor met die M530-65A laminasies het ’n gemeete effektiwiteit bo 89%. Die toets resultate wys dat die RSM as ’n traksie motor gebruik kan word. Die dryfstelsel word in 4de en 5de rat ge-evalueer. Die effektiwiteit van die ratkas in 4de en 5de word benader en ’n effektiwiteit bo 90% is verkry. Hierdie hoë effektiwiteit maak die veranderlike spoed ratkas ’n lewensvatbare mededinger in die EV dryfstelsel.