Initial user survey and analysis of market potential were aimed at ensuring that vehicle demonstrators’ concept meets the users’ needs. Feasibility studies of different multi-wheels tilting vehicles architecture formed the basis for technical specifications in terms of performances (powertrain, handling/stability, comfort) for the vehicles and powertrain components.
A preliminary Business Plan based on market analysis was performed, formulating different business models to enter in the market.
Cost reduction has been achieved by three main streamlines:
Battery Modularity: a universal 48V module 12S4P (18650 Li-Ion cells, 518 Wh capacity) has been used, enabling economies of scale and flexibility of design. BMS has been integrated. Battery pack has structural function in D2 prototype, thus D1 prototype has swappable batteries.
Scalability and functional integration: e-motor control, battery charger and overall vehicle control features are integrated in a single scalable hardware component, with ad-hoc software. The 4kW Drivetrain Management Module (DMM) uses the same hardware and a reconfigurable software. DMM functions have been successfully tested on the demonstrator D3.
Use of State-of-the Art low-cost solutions: investigation of technology transfer from automotive field led to two proposals:
- On board e-motor (electrically excited synchronous machine with claw pole rotor and additional ferrite magnets with inverter integrated)
- On-wheel e-motor (three phase brushless internal permanent magnet motor with planetary gear transmission integrated) for in-wheel installation (2 e-motors), with separated inverters.
RESOLVE design is based on virtual simulations, both for structural and performance analysis, including energy consumption cycles. Virtual mockups led to physical prototypes, fully tested on benches and on track. Energy consumption goals have been achieved, confirming predicted performances.
RESOLVE D1 (L2e) and D2 (L6e) demonstrators are based on TFW architecture, in order to offer enhanced active vehicle stability, comfort and weather protection.
According with their own strategies, RESOLVE OEMs propose two complementary vehicle formulas sharing common characteristics:
• Spontaneous tilting vehicles with roll lock system
• Affordable and energy efficient light weight concepts
• Modular architecture for batteries
• BMS with SOC and SOH estimation
• Electronic system architecture based on same hardware and software
• Increased efficiency of regenerative braking
• Innovative HMI
• Smart range management
Peculiarities to increase attractiveness like enclosed cabin and battery swapping features have been also proposed in different demonstrators.
Rider experience was improved by implementing algorithms for stability control and handling (i.e. automatic stand-up at low speeds, roll-motion dampening, traction control and electronic differential), regenerative braking (that allows for a range increase about 12% on test cycles) and smart range management for reducing range anxiety.
Innovative HMI (on-board display and smartphone) and controls enable a safer, comfortable and ergonomic interaction between rider and vehicle.