Specifying a hydraulic regenerative braking system for an articulated urban delivery vehicle
Previous research has shown that hydraulic systems offer potentially the lightest and smallest regenerative braking technology for heavy goods vehicles. This paper takes the most practical embodiment of a hydraulic system for an articulated urban delivery vehicle and investigates the best specification for the various components, based on a simulated stop-start cycle. The potential energy saving is quantified.
Comparison of regenerative braking technologies for heavy vehicles
Project Overview Problem: • Urban freight delivery by truck is growing • Current methods are inefficient with regards to the energy expended per tonne of material moved • Using longer vehicles with steerable trailer axles can reduce energy consumption by up to 25% • Using regenerative braking can reduce energy consumption by a further 30% Goals: • Develop an ultra low-energy urban freight delivery vehicle • Prove the viability of constructing a trailer with steered axles and regenerative braking
Vehicle dynamics model for predicting maximum truck acceleration levels
The paper presents a simple vehicle dynamics model for estimating maximum vehicle acceleration levels based on a vehicle's tractive effort and aerodynamic, rolling, and grade resistance forces. In addition, typical model input parameters for different vehicle, pavement, and tire characteristics are presented. The model parameters are calibrated/validated against field data that were collected along the Smart Road test facility at Virginia Tech utilizing a truck and trailer for 10 weight-to-power configurations, ranging from 85 kg/kW to 169 kg/kW (140 lb/hp to 280 lb/hp). The model was found to predict vehicle speeds at the conclusion of the travel along the section to within 5 km/h (3.1 mi/hr) of field measurements, thus demonstrating the validity and applicability of the model.