Final Report Summary - AMBER-ULV (Automotive Mechatronic Baseline for Electric Resilient Ultra Light Vehicle)
Executive Summary:
State of the Art - Background
The energy consumption of conventional vehicles depends from the physical resistance factors which the vehicle has to overcome when in operation, the inefficient power conversion from fuel to wheel movement and the lack of energy recuperation.
The potential contribution of light-weighting to reduce transport energy consumption – especially in urban areas which have more frequent ‘stop-and-go’ situations – has been already identified and highlighted.
Ultra Light Vehicles (ULV) intrinsically have a better efficiency due to their improved transport capability per vehicle mass. Additionally, improved driving dynamics performance can be achieved more easily thanks to the reduced mass.
However, the design of ULV sharing the same road with heavier cars represents a complex technical challenge for achieving acceptable safety levels.
Consumers buy a new vehicle for many and diverse reasons. These include purchase price, depreciation rate, styling, performance and handling, brand preference and social image, but car owners tend to underestimate the costs of running a vehicle. Although they are very well aware of fuel costs, road tax and insurance, they do not always account for servicing, repair and the cost of depreciation.
Therefore, if one is interested in comparing the cost of EV with other competing vehicle technologies the parameter of interest should be the Total Cost of Ownership (TCO).
Objectives
AMBER-ULV project aims to develop and integrate several innovative concepts, resulting from successfully completed R&D projects, giving a socially acceptable answer to safety concerns but not penalising the driving experience of Ultra Light Electric Vehicles.
AMBER-ULV will develop an outstanding 4WD prototype vehicle with a clear industrial strategy and vision in mind, all the research activities will be driven by severe requirements in terms of future exploitability through industrial development.
The vehicle design will be driven by assembly line requirements and will take into consideration the energy intensities of different manufacturing processes. In particular, lifecycle analysis and lifecycle cost will be applied to the composite chassis manufacturing taking care of end-of-life potential reuse and recycling.
Project Context and Objectives:
AMBER-ULV project aimed to close the gap between heavy quadricycles and M1 category vehicles in terms of safety and performances, while maintaining a convenient and affordable price to quality ratio.
The consortium partners developed a mechatronic platform suitable to equip different vehicles architectures, ranging from 2WD to AWD configurations and adopting any available motor technology thanks to its Unified Control Platform.
The developed AMBER-ULV “Country Race” prototype can be equipped with a single battery pack located under the rear seats or extend its range and performances with an additional battery pack located at the bottom, duly protected by a composite battery tray and by the innovative hybrid metal composite chassis.
Fast replacement requirements inspired the design of the battery tray, and then the two Battery Management System (BMS) electronic circuits have been directly integrated within the battery pack.
A similar solution has been shared with the main battery pack design, positively influencing industrial assembly processes and maintenance operations during vehicle lifetime.
The chassis designers explored the adoption of simple shape CFRP sill beams for rapid tooling and fast composite material production processes, coupled with steel tubular trusses for the roll bar and for the motor and suspension attachments.
The compact city car design of AMBER-ULV four seater, characterized by a short bonnet, side by side with a relevant mass in running order when both battery packs are installed on board, suggested looking for the adoption of high-energy absorption materials for the frontal crash boxes.
For the reason above, a composite sandwich solution inspired by Formula 1 nose boxes has been implemented and tested in the demanding Offset-Deformable Barrier (ODB) crash test at 64 km/h impact speed according to Euro NCAP protocol.
Despite the challenging crash scenario, the composite sill beams showed their capability to protect occupants and batteries, while the crash boxes required a design review cycle looking for improved joint design and optimal crushing behaviour in terms of stiffness and deceleration profile.
In the Side Mobile Barrier crash test with 50 km/h impact speed, the anti-intrusion bar and the custom door interlocking at hinges showed their potential in conjunction with the sill beams.
The acceleration profile recorded in the ODB crash test has been used as input for the virtual development and evaluation of a full restraint system including seatbelt pretensioners and driver airbags, showing that ultra light electric vehicles can potentially achieve similar safety performances of internal combustion vehicles despite the penalties related to batteries mass.
The running prototype showed high stability characteristics for the category, showing the beginning of unstable behaviour in the Sine With Dwell (SWD) manoeuvre around 70 km/h at 120 degree steering angle.
However, the consortium introduced a novel Traction Control and Stability System (TCSS), based on individual wheel braking through a custom electro mechanic actuator and controlled by a stability algorithm derived from classic ESC.
The TCSS aims to be a low cost solution for a wide range of Electric Vehicles that cannot benefit from available commercial systems, generally affordable in case of medium to large production volumes only.
Project Results:
AMBER-ULV “Country Race” achieved driving performances in line with the objectives such as a maximum speed exceeding 100 km/h, a NEDC cycle range around 228 km, acceleration from 0 to 70 km/h in 14 s and emergency braking distance from 80 km/h to complete stop in 25 meters thanks to deep regenerative braking.
A long list of exploitable results has been achieved:
Highly deformable crashbox
The motorsport technology adopted in Formula 1 noseboxes has been transferred to a small urban electric vehicle. The benefits reside in the high energy absorption capability of composite materials crushing mechanism, the drawbacks in the complex engineering. The project led to useful experimental test and to the development of simulation capabilities useful to foster a wider adoption of this innovative solution.
Composite battery tray
The composite battery tray showed excellent behaviour in frontal and lateral crash, validating its adoption as a possible answer to battery related safety concerns. As part of a modular system located at vehicle bottom, the battery tray can be easily substituted for maintenance or added aftermarket as an option.
Unified motor control algorithm and more integrated inverter power stage
The successful development of a unified algorithm to drive different motor technologies with the same inverter power stage represents a great market opportunity to provide a flexible powertrain components to different vehicle manufacturers developing a variety of electric vehicles.
Modular BMS with active equalizer
The AMBER-ULV modular BMS can monitor groups of cells and the combination of those groups at higher level, providing battery pack with different energy storage capacity. All the electronics reside within the assembled battery pack so that installation and substitution are greatly simplified.
Multi Functional Unit
The MFU is the first interface between the driver and the vehicle. Many commands and switches have been integrated in the touch panel, thus saving on cables routing. The MFU has navigation and status monitoring capabilities and can be directly connected to EOS manufacturer offering instant support during emergency.
Hybrid composite metal chassis
AMBER-ULV chassis must be light, stiff, safe and cheap. It has been designed by NOVA and Formtech connecting carbon fiber sillbeams with steel tubular trusses and folded metal sheets. The sillbeams demonstrated their high potential in protecting occupants and batteries in lateral crash
Methodology for acoustic analysis of EVs
CESI research on AMBER-ULV made more accessible the evaluation of acoustic performances of electric vehicles so that even small builders can benefit, on a consultancy basis, of quality results before proposing their new models.
Business models for future urban vehicles
The work done during the project made available different business models that can be tailored by NTU according to different vehicles and mission profile.
EV vehicle stakeholder database
NTU collected a relevant database of EV stakeholders that can be accessed on a service basis in parallel with consultancy and support in the definition of a new project or simply looking for suppliers.
New Amesim models and tools for stability and EV powertrain analysis
Siemens took profit of AMBER-ULV to develop new models and tools which will be integrated in the Amesim commercial sw and released in future versions.
EV production concept
The factory planning for a growing company willing to build EVs is a complex task. Fraunhofer and CESI proposed their integrated simulation approach to support the manufacturer from the pre-series to mass production.
Virtual integration procedure
Sherpa developed a methodology for integrating in a fast and reliable way different controllers, hardware and sensors. The procedure can dramatically reduce the development phase of complex EV projects.
Traction control algorithm
UNIBO developed a novel traction control algorithm for deep regenerative breaking, fully validated by AMBER-ULV demonstrator.
Stability control algorithm
TNO customized its stability algorithm making it capable to drive non conventional actuators, such as the TCSS equipping AMBER-ULV demonstrator.
TCSS actuator and low level controller
The Traction Control and Stability System actuator is EOS answer to limited off the shelf options for small production volumes. With relatively low cost hardware a stability algorithm can equip almost any EV quadricycle or M1 small series vehicle.
Functional safety assessment concept
Fraunhofer IPA dealt with ASIL and ISO 26262 regulation to understand the criticalities related to the growing introduction of EVs in the urban vehicle market. IPA will make available its experience for further research or consultancy.
Crash test assessment and ESC assessment
TNO had the opportunity to follow the whole design process and the safety assessment of a prototypal EV, adding new elements to its wide knowledge of transport technology. TNO will make available its experience for further research or consultancy.
Potential Impact:
AMBER-ULV can impact the way future electric vehicles will be designed and manufactured.
Major trends in automotive are leading towards increased complexity, hybrid powertrains, a lot of comfort accessories and driver assistance technologies.
Purely electric vehicles are still penalized by battery weight and power consumption.
AMBER-ULV proposes a clever solution to range anxiety, simply offering two battery packages: a main one, permanently installed below the rear seats can be used for everyday driving experience, the extension battery at vehicle bottom and fully protected by the composite battery tray can be used if and when needed, thanks to a quite simple vehicle interfacing.
For example vehicle owners could rent the extension battery for their vacations, or use it all year long if their commuting distance to workplace is longer.
To take profit of the extended range, the battery related extra weight put pressure on the safety aspects.
AMBER-ULV explored new concepts like only a research project can do, trying to introduce composite materials for mission critical functional tasks, such as crashworthiness, instead of using expensive carbon fiber for purely aesthetical reasons or for reducing some bodywork panel weight.
That posed a challenge that experts from civil aviation know very well, the crushing behaviour of composite materials is hard to model and repeatability is difficult to achieve.
However, the extensive adoption of composite materials seems to be written in the future of electric vehicles, at least until new battery technologies will grant huge weight savings.
AMBER-ULV has been presented at FKFS Symposium 2016 in Stuttgart with a dedicated session and many visitors reached the project stand to learn more about the project.
The same happened at IDTechEx Show 2016 in Berlin, where AMBER-ULV has been awarded by a free boot within the EV Launchpad.
State of the Art - Background
The energy consumption of conventional vehicles depends from the physical resistance factors which the vehicle has to overcome when in operation, the inefficient power conversion from fuel to wheel movement and the lack of energy recuperation.
The potential contribution of light-weighting to reduce transport energy consumption – especially in urban areas which have more frequent ‘stop-and-go’ situations – has been already identified and highlighted.
Ultra Light Vehicles (ULV) intrinsically have a better efficiency due to their improved transport capability per vehicle mass. Additionally, improved driving dynamics performance can be achieved more easily thanks to the reduced mass.
However, the design of ULV sharing the same road with heavier cars represents a complex technical challenge for achieving acceptable safety levels.
Consumers buy a new vehicle for many and diverse reasons. These include purchase price, depreciation rate, styling, performance and handling, brand preference and social image, but car owners tend to underestimate the costs of running a vehicle. Although they are very well aware of fuel costs, road tax and insurance, they do not always account for servicing, repair and the cost of depreciation.
Therefore, if one is interested in comparing the cost of EV with other competing vehicle technologies the parameter of interest should be the Total Cost of Ownership (TCO).
Objectives
AMBER-ULV project aims to develop and integrate several innovative concepts, resulting from successfully completed R&D projects, giving a socially acceptable answer to safety concerns but not penalising the driving experience of Ultra Light Electric Vehicles.
AMBER-ULV will develop an outstanding 4WD prototype vehicle with a clear industrial strategy and vision in mind, all the research activities will be driven by severe requirements in terms of future exploitability through industrial development.
The vehicle design will be driven by assembly line requirements and will take into consideration the energy intensities of different manufacturing processes. In particular, lifecycle analysis and lifecycle cost will be applied to the composite chassis manufacturing taking care of end-of-life potential reuse and recycling.
Project Context and Objectives:
AMBER-ULV project aimed to close the gap between heavy quadricycles and M1 category vehicles in terms of safety and performances, while maintaining a convenient and affordable price to quality ratio.
The consortium partners developed a mechatronic platform suitable to equip different vehicles architectures, ranging from 2WD to AWD configurations and adopting any available motor technology thanks to its Unified Control Platform.
The developed AMBER-ULV “Country Race” prototype can be equipped with a single battery pack located under the rear seats or extend its range and performances with an additional battery pack located at the bottom, duly protected by a composite battery tray and by the innovative hybrid metal composite chassis.
Fast replacement requirements inspired the design of the battery tray, and then the two Battery Management System (BMS) electronic circuits have been directly integrated within the battery pack.
A similar solution has been shared with the main battery pack design, positively influencing industrial assembly processes and maintenance operations during vehicle lifetime.
The chassis designers explored the adoption of simple shape CFRP sill beams for rapid tooling and fast composite material production processes, coupled with steel tubular trusses for the roll bar and for the motor and suspension attachments.
The compact city car design of AMBER-ULV four seater, characterized by a short bonnet, side by side with a relevant mass in running order when both battery packs are installed on board, suggested looking for the adoption of high-energy absorption materials for the frontal crash boxes.
For the reason above, a composite sandwich solution inspired by Formula 1 nose boxes has been implemented and tested in the demanding Offset-Deformable Barrier (ODB) crash test at 64 km/h impact speed according to Euro NCAP protocol.
Despite the challenging crash scenario, the composite sill beams showed their capability to protect occupants and batteries, while the crash boxes required a design review cycle looking for improved joint design and optimal crushing behaviour in terms of stiffness and deceleration profile.
In the Side Mobile Barrier crash test with 50 km/h impact speed, the anti-intrusion bar and the custom door interlocking at hinges showed their potential in conjunction with the sill beams.
The acceleration profile recorded in the ODB crash test has been used as input for the virtual development and evaluation of a full restraint system including seatbelt pretensioners and driver airbags, showing that ultra light electric vehicles can potentially achieve similar safety performances of internal combustion vehicles despite the penalties related to batteries mass.
The running prototype showed high stability characteristics for the category, showing the beginning of unstable behaviour in the Sine With Dwell (SWD) manoeuvre around 70 km/h at 120 degree steering angle.
However, the consortium introduced a novel Traction Control and Stability System (TCSS), based on individual wheel braking through a custom electro mechanic actuator and controlled by a stability algorithm derived from classic ESC.
The TCSS aims to be a low cost solution for a wide range of Electric Vehicles that cannot benefit from available commercial systems, generally affordable in case of medium to large production volumes only.
Project Results:
AMBER-ULV “Country Race” achieved driving performances in line with the objectives such as a maximum speed exceeding 100 km/h, a NEDC cycle range around 228 km, acceleration from 0 to 70 km/h in 14 s and emergency braking distance from 80 km/h to complete stop in 25 meters thanks to deep regenerative braking.
A long list of exploitable results has been achieved:
Highly deformable crashbox
The motorsport technology adopted in Formula 1 noseboxes has been transferred to a small urban electric vehicle. The benefits reside in the high energy absorption capability of composite materials crushing mechanism, the drawbacks in the complex engineering. The project led to useful experimental test and to the development of simulation capabilities useful to foster a wider adoption of this innovative solution.
Composite battery tray
The composite battery tray showed excellent behaviour in frontal and lateral crash, validating its adoption as a possible answer to battery related safety concerns. As part of a modular system located at vehicle bottom, the battery tray can be easily substituted for maintenance or added aftermarket as an option.
Unified motor control algorithm and more integrated inverter power stage
The successful development of a unified algorithm to drive different motor technologies with the same inverter power stage represents a great market opportunity to provide a flexible powertrain components to different vehicle manufacturers developing a variety of electric vehicles.
Modular BMS with active equalizer
The AMBER-ULV modular BMS can monitor groups of cells and the combination of those groups at higher level, providing battery pack with different energy storage capacity. All the electronics reside within the assembled battery pack so that installation and substitution are greatly simplified.
Multi Functional Unit
The MFU is the first interface between the driver and the vehicle. Many commands and switches have been integrated in the touch panel, thus saving on cables routing. The MFU has navigation and status monitoring capabilities and can be directly connected to EOS manufacturer offering instant support during emergency.
Hybrid composite metal chassis
AMBER-ULV chassis must be light, stiff, safe and cheap. It has been designed by NOVA and Formtech connecting carbon fiber sillbeams with steel tubular trusses and folded metal sheets. The sillbeams demonstrated their high potential in protecting occupants and batteries in lateral crash
Methodology for acoustic analysis of EVs
CESI research on AMBER-ULV made more accessible the evaluation of acoustic performances of electric vehicles so that even small builders can benefit, on a consultancy basis, of quality results before proposing their new models.
Business models for future urban vehicles
The work done during the project made available different business models that can be tailored by NTU according to different vehicles and mission profile.
EV vehicle stakeholder database
NTU collected a relevant database of EV stakeholders that can be accessed on a service basis in parallel with consultancy and support in the definition of a new project or simply looking for suppliers.
New Amesim models and tools for stability and EV powertrain analysis
Siemens took profit of AMBER-ULV to develop new models and tools which will be integrated in the Amesim commercial sw and released in future versions.
EV production concept
The factory planning for a growing company willing to build EVs is a complex task. Fraunhofer and CESI proposed their integrated simulation approach to support the manufacturer from the pre-series to mass production.
Virtual integration procedure
Sherpa developed a methodology for integrating in a fast and reliable way different controllers, hardware and sensors. The procedure can dramatically reduce the development phase of complex EV projects.
Traction control algorithm
UNIBO developed a novel traction control algorithm for deep regenerative breaking, fully validated by AMBER-ULV demonstrator.
Stability control algorithm
TNO customized its stability algorithm making it capable to drive non conventional actuators, such as the TCSS equipping AMBER-ULV demonstrator.
TCSS actuator and low level controller
The Traction Control and Stability System actuator is EOS answer to limited off the shelf options for small production volumes. With relatively low cost hardware a stability algorithm can equip almost any EV quadricycle or M1 small series vehicle.
Functional safety assessment concept
Fraunhofer IPA dealt with ASIL and ISO 26262 regulation to understand the criticalities related to the growing introduction of EVs in the urban vehicle market. IPA will make available its experience for further research or consultancy.
Crash test assessment and ESC assessment
TNO had the opportunity to follow the whole design process and the safety assessment of a prototypal EV, adding new elements to its wide knowledge of transport technology. TNO will make available its experience for further research or consultancy.
Potential Impact:
AMBER-ULV can impact the way future electric vehicles will be designed and manufactured.
Major trends in automotive are leading towards increased complexity, hybrid powertrains, a lot of comfort accessories and driver assistance technologies.
Purely electric vehicles are still penalized by battery weight and power consumption.
AMBER-ULV proposes a clever solution to range anxiety, simply offering two battery packages: a main one, permanently installed below the rear seats can be used for everyday driving experience, the extension battery at vehicle bottom and fully protected by the composite battery tray can be used if and when needed, thanks to a quite simple vehicle interfacing.
For example vehicle owners could rent the extension battery for their vacations, or use it all year long if their commuting distance to workplace is longer.
To take profit of the extended range, the battery related extra weight put pressure on the safety aspects.
AMBER-ULV explored new concepts like only a research project can do, trying to introduce composite materials for mission critical functional tasks, such as crashworthiness, instead of using expensive carbon fiber for purely aesthetical reasons or for reducing some bodywork panel weight.
That posed a challenge that experts from civil aviation know very well, the crushing behaviour of composite materials is hard to model and repeatability is difficult to achieve.
However, the extensive adoption of composite materials seems to be written in the future of electric vehicles, at least until new battery technologies will grant huge weight savings.
AMBER-ULV has been presented at FKFS Symposium 2016 in Stuttgart with a dedicated session and many visitors reached the project stand to learn more about the project.
The same happened at IDTechEx Show 2016 in Berlin, where AMBER-ULV has been awarded by a free boot within the EV Launchpad.