As part of an electric tracked vehicle propulsion system, E-X-Drive® offers a lighter, more compact and efficient solution compared with conventional mechanical transmission systems.
E-X-Drive® combines electrical and mechanical components in a novel configuration that is efficiently packaged, incorporates mechanical regenerative transfer of steering power, range-shift mechanisms, and permanent magnet motor technology. E-X-Drive® is a demonstrated and low risk solution, with low stress levels in the motors, gears, shafts and bearing components.
Using E-X-Drive® as part of an electric propulsion system offers the opportunity for innovative tracked vehicle configurations founded on a fundamental shift in platform design trade space options. Not only is an E-X-Drive®-based transmission package smaller and lighter than comparable conventional transmissions it also lends itself to novel vehicle layouts to improve survivability, agility, and mission success.
Building on our technical expertise across highly integrated electromechanical transmissions, our new electric hub drive is intended to revolutionise the mobility and performance of wheeled military vehicles. As part of an electric propulsion system, in-wheel hub drives replace the main transmission and ‘drop-boxes’, differentials, and drive shafts with compact and extremely high-powered electric motors contained completely within the wheel rim. As part of a series hybrid-electric powertrain, this approach opens up dramatic new design possibilities that increase performance and improve safety and survivability of military vehicles.
QinetiQ offer a family of Hub Drive Units (HDU) providing a compact in-wheel solution that fits within a standard 20” tyre rim delivering more power, torque, and mobility compared with conventional mechanical transmission systems. Our Hub Drive is uniquely packaged containing a permanent magnet motor, 3-stage gearbox, integrated brake, with water based cooling.
The Hub Drive is offered with an accompanying umbilical system and Wheel Station Controller (WSC). Each hub drive is controlled by an individual WSC containing the power inverter, controller, and pneumatics for the gear shift. These are delivered through the custom built armoured umbilical system.
The hub drive system delivers two critical areas of benefits:
Understand the Hybrid Electric Powertrain system integration
QinetiQ offer customers a complete understanding of the impact integrating a Hybrid Electric Powertrain (HEP) system has on their vehicle including performance and cost through the use of our validated HYSIM® model.
HYSIM® – Capability Overview
QinetiQ offers simulation capabilities in the form of a validated computer model known as ‘HYSIM®’. At its core HYSIM® is a powertrain simulation tool used to assess various technology and configuration options for both conventional and hybrid electric drive systems in the context of wheeled and tracked vehicles. It is ideal for performing iterative concept studies (at a systems level) to quantify the benefits of transitioning to a hybrid electric system (from a conventional one). The model takes into account the major longitudinal forces that affect vehicle propulsion (i.e. aerodynamic drag, rolling resistance and gradient forces), and hence the influence on fuel consumption and acceleration.
HYSIM is capable of predicting vehicle performance and fuel consumption for various powertrain topologies including conventional systems, series HEVs (Hybrid Electric Vehicles), and parallel HEVs. It consists of a powertrain model built in SIMULINK that is linked to an MS-Access database of input, output and sub-model data. The primary components in the model comprise the ‘duty cycle’ definition, engine, generator, battery, transmission, and electric motor.
Integration cost and planning
QinetiQ also provide the service of ‘True Planning’ to customers. This provides a clear insight into the cost of integrating a Hybrid Electric Powertrain to their vehicle, the required work-packages and schedule associated. This can be broken down into the prototype phase, production phase, and through life costing.
The cost analysis for the implementation, development, and through life is conducted through familiarity of market costs and a thorough market analysis to inform the price.
Additionally, a timeline is produced by breaking the project into work-packages illustrating what is required to achieve the final solution.
Q-Shift has developed a high performance low cost gear change technology. It uses simple dog clutch components to pass the driving torque directly from one gear to the next without passing through a neutral state. Its sequential shift event is controlled mechanically via a simple barrel arrangement. Additional patents in the portfolio take this concept further, including a version which seamlessly multiplies the number of ratios.
Vehicle Drive Technology
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