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Negotiating the Steering Control Authority within Haptic Shared Control Framework

University of North Carolina Charlotte-Vahid Izadi, Amir H. Ghasemi, Pouria Karimi Shahri
  • Technical Paper
  • 2020-01-1031
To be published on 2020-04-14 by SAE International in United States
Communication and cooperation among team members can be enhanced significantly with physical interaction. Successful collaboration requires the integration of the individual partners' intentions into a shared action plan, which may involve a continuous negotiation of intentions and roles. This project aims to explore the underlying process of intention integration and develop models for consensus reaching in a haptic shared control framework. We pay particular attention to the role of impedance modulation as a mechanism for negotiation of intentions across the physical or haptic channel. We present an optimal control-based methodology for an automation system to modulate its impedance to either gain or yield the authority to the human driver.
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Modelling and Control of Multi-Vehicle Traffic Networks Using an Integrated VISSIM-Matlab Simulation Platform

University of North Carolina Charlotte-Shubhankar Chintamani Shindgikar, Pouria Karimi Shahri, Amir H. Ghasemi
  • Technical Paper
  • 2020-01-0887
To be published on 2020-04-14 by SAE International in United States
This paper aims to develop a platform for integrating PTV VISSIM and MATLAB Simulink to design and analyze the flow of traffic in an urban traffic network. We model a non-signalized traffic network in VISSIM. From VISSIM, we take the inflow and outflow rates data and send them to the controller in MATLAB through a VISSIM Component Object (COM) interface. By employing an extremum seeking approach, an optimal velocity is determined and sent back to VISSIM through the COM interface. Numerical simulation demonstrates the effectiveness of the platform for testing different traffic control approaches and optimizing flow.
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Traffic Control Strategies for Congested Heterogeneous Multi-Vehicle Networks

University of North Carolina Charlotte-Pouria Karimi Shahri, Amir H. Ghasemi, Vahid Izadi
  • Technical Paper
  • 2020-01-0086
To be published on 2020-04-14 by SAE International in United States
The primary goal of this paper is to pioneer and develop robust and adaptive algorithms for controlling autonomous vehicles in heterogeneous networks with the aim of maximizing the performance (in terms of mobility) and minimizing variation in the network. While the fundamental approaches and models proposed in this research can be applied to any heterogeneous multi-agent system, we select heterogeneous traffic networks as a set-up for exploring the proposed research. We consider the heterogeneity in the system in the form of a mix of autonomous and human-driven vehicles (different levels of autonomous vehicle penetration). We propose a two-level hierarchical controller wherein the upper-level controller, an optimization problem using the concept of macroscopic fundamental diagram is formulated to deal with the traffic demand balance problem. At the lower level, using the microscopic models of the network, the control actions for each vehicle will be determined such that he optimal flow received from the upper-level controllers can be tracked.
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Modelling Non Cooperative Human-Automation Interactions in a Haptic Shared Control Framework

University of North Carolina Charlotte-Amirhossein Ghasemi, Arjun Yeravdekar
Published 2019-04-02 by SAE International in United States
This paper addresses the interaction between the human driver and automation system in a Haptic Shared Control framework using a non-cooperative model predictive game approach. We model the human and automation’s interaction in a scenario when both driver and automation system detects an obstacle but select different paths for avoiding it. For such a situation, the effects of varying information patterns, namely the Nash and Stackelberg strategies on the shared steering angle are investigated. The simulation demonstrates the influences of the path-following weights on negotiating control authority between the human driver and the automation system.
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Waste Heat Recovery System for a Turbocharged Diesel Generator at Full and Part Load Operating Conditions Using Rankine and Organic Rankine Cycles

University of North Carolina Charlotte-Shreyas Joshi, Saisri Aditya Kanchibhotla
University of South Australia-Saiful Bari
Published 2018-04-03 by SAE International in United States
Waste Heat Recovery System (WHRS) is used to extract heat from the exhaust gas from internal combustion (IC) engines to produce additional power with increase in overall efficiency of the engine. Amongst various WHRS, this paper focuses on WHRS using Rankine Cycle (RC) and Organic Rankine Cycle (ORC). A 100 kVA (80 kW engine) diesel generator was used for this research. Water, R245fa, and R134a were used as the working fluids for the cycle. To assess the performance of WHRS, the system was designed for 80 kW, 70 kW and 60 kW loads and then, for each designed load the WHRS was run for other loads and then compared. Assessment provide simulation results of RC and ORC using Engineering Equation Solver (EES) software. It was found that using water as the working fluid around 20% additional power was achieved. But it limited the working range of the system making it unsuitable for lower loads of 10 and 20 kW for this generator. R245fa and R134a on the other hand provided comparatively less efficiency but covered…
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Optimum Design Point to Recover Maximum Possible Exhaust Heat Over the Operating Range of a Small Diesel Truck Using Bottoming Rankine Cycle

University of North Carolina Charlotte-Saisri Aditya Kanchibhotla
University of South Australia-Saiful Bari
Published 2018-04-03 by SAE International in United States
This paper focuses on waste heat recovery (WHR) system, which is an efficient technology to reduce fuel and vehicle carbon dioxide (CO2) emissions per kW of power produced. Wide variations of power of a vehicle make it difficult to design a WHR system which can operate optimally at all powers. The exhaust temperature from the engine is critical to design a WHR system. Higher the temperature higher will be the gain from the WHR system. However, as power drops the exhaust temperature drops which makes the WHR system perform poorly at lower powers. In this research, a small diesel truck engine was used to design a WHR system to produce additional power using a Rankine cycle (RC). The WHR system was designed at the rated power and speed of 42.8 kW and 2600 rpm, respectively. At this design point, around 15% additional power improvement was achieved resulting around 13% break specific fuel consumption reduction. Next, the performances of the WHR system were evaluated at different operating points lower than the rated power of the engine covering…
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Effects of Variable Intake Valve Timings and Valve Lift on the Performance and Fuel Efficiency of an Internal Combustion Engine

University of North Carolina Charlotte-Pauras Sawant
University of South Australia-Saiful Bari
Published 2018-04-03 by SAE International in United States
To comply with the new Corporate Average Fuel Economy (CAFE) standards, automakers are expected to increase the average fuel economy of their vehicles to 54.5 miles per gallon from the current 24.8 miles per gallon by 2025. This research aims at proposing a feasible solution to narrow down the gap between the current and expected fuel economy of the vehicles, yet maintaining the engine’s original performance. A standard model of the KTM 510 cc single cylinder, fuel injected, internal combustion engine (IC) engine is modelled and simulated in Ricardo Wave software package to map the stock engine performance and specific fuel consumption at wide open throttle (WOT). The baseline simulation model is validated against the experimental readings with 98% accuracy. The intake valve timings (IVO, IVC), valve lift and profile, being major contributors to the wave and gas dynamics in the combustion chamber are then varied at all engine speeds to capture the amplified induction pressure wave to boost the volumetric and thermal efficiency and attain optimized engine performance. As a combined effect of varying the above parameters,…
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Effect of Integrating Variable Intake Runner Diameter and Variable Intake Valve Timing on an SI Engine’s Performance

University of North Carolina Charlotte-Shashank Ghodke
University of South Australia-Saiful Bari
Published 2018-04-03 by SAE International in United States
Design of the intake system of an internal combustion (IC) engine is one of the critical parameters to improve the performance of an engine. Induction pressure waves (compression and rarefaction waves) are created in the intake runner due to valve operations. If the intake runner is tuned correctly, a compression wave can boost the intake air flow improving the volumetric efficiency which increases the torque and power of the engine. In this research, the intake runner diameter and valve timing were varied individually, after which both were varied together to achieve optimum volumetric efficiency. A single-cylinder, four-stroke spark-ignited 510 cc naturally aspirated engine was used for the analysis. Simulations were carried out using engine simulation software Ricardo Wave to find the effect of intake runner diameter and timing on the engine performance. A chassis-dyno test was made on the engine to know its factory state performance and compared the torque and power with the simulation data. As a result, the validated model is found to have a deviation of around 10.0% from the actual chassis dyno…
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Design and Optimization of Exhaust Gas Heat Recovery System Based on Rankine Cycle and Organic Cycles

University of North Carolina Charlotte-Saisri Aditya Kanchibhotla, Shreyas Joshi
University of South Australia-Saiful Bari
Published 2018-04-03 by SAE International in United States
In this paper, a waste heat recovery (WHR) system is designed to recover heat from the exhaust of a diesel-gen-set having an engine of 26.57 kW. The Rankine Cycle (RC) and the Organic Rankine Cycle (ORC) are used to produce additional power using water, R113, R124 and R245fa as the working fluids. Water as the working fluid gives the best improvement of 13.8% power improvement with 12.2% bsfc reduction, but fails to produce any power at the lowest operating power of 5.8 kW due to lower exhaust temperature and higher boiling point of water. This is when the WHR system is designed at the rated power of 26.57 kW. Designing at lower power of 20.0 kW improves the enhancements at this and lower powers but reduces the improvement at the rated power of 26.57 kW. This design again fails to produce any power at the lowest power. On the other hand, R113, R124 and R245fa which have much lower boiling points manage to produce additional power at the lowest power, but the improvements at other…
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An Experimental Study on Engine Dynamics Model Based In-Cylinder Pressure Estimation

University of North Carolina Charlotte-Ahmed Soliman
Delphi Corporation-Feilong Liu
Published 2012-04-16 by SAE International in United States
The information provided by the in-cylinder pressure signal is of great importance for modern engine management systems. The obtained information is implemented to improve the control and diagnostics of the combustion process in order to meet the stringent emission regulations and to improve vehicle reliability and drivability. The work presented in this paper covers the experimental study and proposes a comprehensive and practical solution for the estimation of the in-cylinder pressure from the crankshaft speed fluctuation. Also, the paper emphasizes the feasibility and practicality aspects of the estimation techniques, for the real-time online application. In this study an engine dynamics model based estimation method is proposed. A discrete-time transformed form of a rigid-body crankshaft dynamics model is constructed based on the kinetic energy theorem, as the basis expression for total torque estimation. The major difficulties, including load torque estimation and separation of pressure profile from adjacent-firing cylinders, are addressed in this work and solutions to each problem are given respectively. The experimental results conducted on a multi-cylinder diesel engine have shown that the proposed method…
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