The Challenge
Retrofitting the drive trains of double-decker buses to increase the fuel efficiency of London’s public transportation.
The Solution
Using Cyth’s embedded control system Circaflex paired with the NI RIO SOM, we designed a communication and monitoring system to improve hybrid buses’ regenerative braking and efficiency.
The Cyth Story
Vantage Power’s diesel hybrid drive train technology was retrofitted onto the existing double-decker buses of London’s public transportation fleet.
Cyth’s embedded control platform, Circaflex, provides scalability for our customer’s I/O requirements as the hybrid monitoring system (HMS) communicates with a diesel and hybrid motor controller and the vehicle’s brake system.
Packaged into our HMS was the NI RIO SOM which provides highly deterministic and safety-critical functions. The quick processing of inputs such as the driver's gas & brake pedals, and diesel engine power vs. hybrid engine power levels are accounted for in high-speed repeating calculations.
The Hybrid Monitoring System (HMS) is programmed in LabVIEW software to ensure the benefits of a real-time processor and a user-programmable FPGA.
Left: The HMS’s rugged weather-proof and vibration-proof enclosure. Center: The Circaflex provides scalable I/O for the HMU’s communication and monitoring requirements. Right: Input and output connectors located in the enclosure exterior, for example, 4 CAN bus connectors for high-speed data communication.
Delivering the Outcome
Overall, Vantage Power’s double-decker hybrid powertrain system incorporated Circaflex and NI sbRIO SOM boards for a 40% greater fuel efficiency across all vehicles retrofitted amongst the London fleet. Our Circaflex HMS system provides the communication and monitoring capabilities required of a hybrid drive train. The large number of subcomponents working together in the hybrid power train such as the hybrid battery and motor, diesel engine, regenerative braking system, generator, driver inputs, etc. show the value of a control system with scalable I/O as well as high-speed data acquisition. The NI hardware and software platform enables a deterministic system for the repetitive calculations of the bus's critical functions further improving the functionality and passenger safety of London’s hybrid fleet.
Technical Specifications
1 x Circaflex 315
1 x Mezzanine Board
1 x NI sbRIO-9651SOM
1 x Custom Weather-proof Enclosure
Circaflex Modules
1 x Inertial Measurement Module
1 x GPS Module
Qty 1 x 16 ch 24V Industrial Digital Input Modules (Sinking & Sourcing)
Qty 1 x 16 ch 24V Industrial Digital Output Modules (Sinking & Sourcing)
Qty 1 x 8ch Analog Voltage Input Module, 100kS/s. 16-bit
Qty 1 x 8ch Analog Current Input Module, 100kS/s, 16-bit
Qty 1 x 8ch Analog Voltage Output Module, 100kS/s, 16-bit
Qty 1 x Strain Gauge
1 x K-Type Thermocouple
I/O Connectors
4 x CANbus
2 x Input DOS
1 x Industrial Digital Input
2 x Analog Input