Abstract

technology is increasingly used in mobile settings, energy and battery management is becoming a part of everyday life. Many have experienced how quickly a battery can be depleted in a smartphone, laptop or electric cars, sometimes causing much distress. An important question is how we can understand and work with energy as a factor in interaction design to enable better experiences for end-users. Through design-oriented research, I have worked with the specific case of electric cars, which is currently a domain where people struggle in terms of energy management. The main issue in this use case is that current driving range estimates cause distrust and anxiety among drivers. Through sketches, prototypes and studies, I investigated causes as well as possible remedies to this situation. My conclusion is that instead of providing black-boxed predictions, in-car interfaces should expose the logics of estimates so that drivers know how their own actions in e.g. driving style, climate control, and other equipment, affects energy use. Revealing such energy mechanisms will not only empower the driver, it will also acknowledge the impact of variables that cannot be predicted automatically. In this work, understanding the dynamic aspects of energy has emerged as central to interaction with systems. This points to a need to design energy sensitive interactions - focusing on supporting users to find the right balance between energy use and the experiential values sought for. To ease design of energy sensitive interactions, energy use is divided into three different categories with accompanying ideals. These are exergy (always needed to achieve the required interaction), intergy (controllable and changing over time and use, needs to be addressed in design), and anergy (always waste that needs to be reduced). This articulation highlights aspects of energy that are specific to interaction design, and possible aspects to expose to allow more energy-efficient interactions in use.  I takt med att vi använder alltmer teknik i mobila sammanhang blir energi- och batterihantering en allt större del av vår vardag. Många har erfarenheter av de besvär som ett plötsligt urladdat batteri i en mobiltelefon, laptop eller elbil kan orsaka. En central fråga för att uppnå bättre användarupplevelser är hur vi kan förstå och arbeta med energi som en faktor i design av interaktion med mobil teknik. Genom designdriven forskning har jag arbetat specifikt med interaktionen i elbilar, en situation där många brottas med just hantering och förståelse av begränsad energi. En specifik utmaning i denna kontext är den misstro som många upplever kring existerande system för räckviddsberäkning. Genom skisser, prototyper och användarstudier har jag undersökt orsaker och praktiska lösningar på detta problem. Min slutsats är att bilens gränssnitt bör exponera den inre logik som beräkningarna bygger på, så att föraren förstår hur egna handlingar, såsom körsätt och användning av t ex kupévärmare, påverkar energiförbrukning och räckvidd. Detta leder till ökad upplevelse av kontroll för föraren, och samtidigt till mer tillförlitliga beräkningar då det tar hänsyn till variabler som inte kan förutsägas automatiskt. I arbetet har dynamiska aspekter av energi framträtt som centralt i användning av interaktiva system. Detta pekar på behovet av att designa energikänsliga interaktioner, som hjälper användaren att förstå balansen mellan energiåtgång och bruksvärde. För att stödja design av energikänsliga interaktioner artikuleras tre kategorier av energianvändning i interaktiva system. Dessa är exergi (behövs för att uppnå tänkt interaktion), intergi (kontrollerbar och föränderlig över tid och användning, måste adresseras med design), och anergi (är alltid ett slöseri som behöver reduceras). Denna artikulation belyser specifikt de aspekter av energiförbrukningen som varierar genom användning, och som skulle kunna exponeras för mer energieffektiv interaktion med ny teknik.  "p"QC 20160429

Abstract

The objective usually considered in sustainable transportation is to minimize pollution due to emissions, and equivalently energy consumption. Turning to electric mobility, pollution is related to electricity production technology, not considered in this research; driving range is the major concern nowadays, due to the limited capacity of batteries and long recharge times . Maximizing the driving range or the level of energy (state of charge of the battery) at destination leads to consider the main factors of energy consumption which are : vehicle weight, engine efficiency and consumption models, drive speed and acceleration, drive pattern, road grade, and payload. We define the electric vehicle travelling salesman problem (EV-TSP) and the electric vehicle routing problem (E-VRP) based on the classical TSP and on the Pollution Routing Problem (PRP) and present models and preliminary results for those problems. Peer reviewed

Abstract

In the current Transport White Paper, the European Union presents a roadmap for a more competitive and sustainable European transport system. Concerning Urban Freight Transport, responsible for about a quarter of CO2 emissions of the transport sector, one of the goals of the EU is to achieve essentially CO2-free city logistics in major urban centres by 2030 by developing and deploying new and sustainable fuels and propulsion systems. The gradual phasing out of ‘conventionally-fuelled’ vehicles from the urban environment contributes to reduce oil dependence, greenhouse gas emissions and local air and noise pollution. To meet European air quality standards, authorities of some major European cities have already introduced Low Emissions Zones where access to urban areas is limited to freight vehicles that meet certain emissions standards. Greater use of low-emission urban trucks based on electric, hydrogen and hybrid technologies would reduce air emissions, but also noise, letting to use road infrastructure more efficiently by making night deliveries and avoiding morning and afternoon peak periods. In addition to their role in the reduction of polluting emissions, the development of low-emission vehicles also allows to mitigate the dependence of the transportation sector to high fossil fuel prices. Electric vehicles have the potential to be powered by renewable energy sources such as wind and solar energy. However, weaknesses can be found in the limited capacity of the battery and the time needed to recharge, and consequently, the limited driving range of electric vehicle. The main sources for final energy consumption are the vehicle size and the engine characteristics, the load factor, the driving pattern, the gradient which represent the average topology of the country, the speed and the acceleration. To maximize the driving range, a routing model, which aims at minimizing the energy consumption, has to be developed. Our paper focus on the Electric Vehicle Traveling Salesman Problem (EV-TSP): given n cities, find the shortest tour, i.e., the shortest directed cycle containing all cities. The classical objective is to minimize the cost tour scheduling to fulfill delivery requests at each location. In this paper we consider the energy cost and we present an extension of the classical problem to minimize the remaining storage capacity of all electric vehicles at the destination node, knowing that there is no recharge operation on the tour. The objective function accounts not just for the travel distance but also on the load of the vehicle and on its speed while the energy consumption of the engine additionally depends on the path to travel, on the slope of the roads and on the vehicle specifications. Moreover, negative consumption that may happen due to regenerative breaking and kinetic energy capture on downhill paths is taken into consideration. Mathematical model is described and computational experiments are performed. Peer reviewed