The advent of autonomous cars creates a range of new questions about road safety, as well as a new collaborative domain for CSCW to analyse. This paper uses video data collected from five countries - India, Spain, France, Chile, and the USA - to study how road users interact with each other. We use interactional video analysis to document how co-ordination is achieved in traffic not just through the use of formal rules, but through situated communicative action. Human movement is a rich implicit communication channel and this communication is essential for safe manoeuvring on the road, such as in the co-ordination between pedestrians and drivers. We discuss five basic movements elements: gaps, speed, position, indicating and stopping. Together these elements can be combined to make and accept offers, show urgency, make requests and display preferences. We build on these results to explore lessons for how we can design the implicit motion of self-driving cars so that these motions are understandable - in traffic - by other road users. In discussion, we explore the lessons from this for designing the movement of robotic systems more broadly.

As self-driving cars have grown in sophistication and ability, they have been deployed on the road in both localised tests and as regular private vehicles. In this paper we draw upon publicly available videos of autonomous and assisted driving (specifically the Tesla autopilot and Google self-driving car) to explore how their drivers and the drivers of other cars interact with, and make sense of, the actions of these cars. Our findings provide an early perspective on human interaction with new forms of driving involving assisted-car drivers, autonomous vehicles and other road users. The focus is on social interaction on the road, and how drivers communicate through, and interpret, the movement of cars. We provide suggestions toward increasing the transparency of autopilots' actions for both their driver and other drivers.

Secondhand retail in the UK charity sector plays a number of important social and economic roles: charity shops are community focal points; money is generated for good causes; and goods are re-circulated that might otherwise be discarded as abject and unwanted. However, like much of the UK high street, the prosperity of charity shops is under significant threat from the rise of internet shopping. Access to online markets via smart phones equips customers to check prices for secondhand items, some customers then deploy information, usually from eBay, to haggle with shop staff. The Haggle-o-Tron playfully subverts both normative and emerging secondhand retail valuation practices by revealing secondhand goods' financial, moral, social and aesthetic properties. This paper reports on how we employ vibrant yet uncomplicated design interventions that embed the charity's values and ethos to reconfigure store-based economic transactions.

Despite the widespread use of mobile devices, details of mobile technology use 'in the wild' have proven difficult to collect. This paper uses video data to gain new insight into the use of mobile computing devices. Our new method combines screen-capture of iPhone use with video recordings from wearable cameras. We use this data to analyse how mobile device use is threaded into other co-present activities, focusing on the use of maps and internet searches. Close analysis reveals novel aspects of gestures on touch screens, how they serve 'double duty' - both as interface gestures but as as resources for ongoing joint action. We go on to describe how users 'walk the blue dot' to orientate themselves, and how searches are occasioned by the local environment. In conclusion, we argue that mobile devices - rather than pushing us away from the world around us - are instead just another thread in the complex tapestry of everyday interaction.

This paper examines routine family car journeys, looking specifically at how passengers assist during a mobile telephone call while the drivers address the competing demands of handling the vehicle, interacting with various artefacts and controls in the cabin, and engage in co-located and remote conversations while navigating through busy city roads. Based on an analysis of video fragments, we see how drivers and child passengers form their conversations and requests around the call so as to be meaningful and paced to the demands, knowledge and abilities of their co-occupants, and how the conditions of the road and emergent traffic are oriented to and negotiated in the context of the social interaction that they exist alongside. The study provides implications for the design of car-based collaborative media and considers how hands- and eyes-free natural interfaces could be tailored to the complexity of activities in the car and on the road.

In-car GPS based satellite navigation systems are now a common part of driving, providing turn-by-turn navigation instructions on smartphones, portable units or in-car dashboard navigation systems. This paper uses interactional analysis of video data from fifteen naturalistically recorded journeys with GPS to understand the navigational practices deployed by drivers and passengers. The paper documents five types of 'trouble' where GPS systems cause issues and confusion for drivers around: destinations, routes, maps & sensors, timing and relevance and legality. The paper argues that to design GPS systems better we need to move beyond the notion of a docile driver who follows GPS command blindly, to a better understanding of how drivers, passengers and GPS systems work together. We develop this in discussing how technology might better support 'instructed action'.

Spectating at sport events is a common and popular leisure activity worldwide. Recently spectating has also become a topic of interest to CHI, particularly the design of technology for both performers and audiences. In this paper we describe an in-depth study of spectating, drawn from fieldwork of outdoor car rallies in the UK and Sweden. We describe three findings with relevance to design: the viewing paradox of spectating, active spectating and the role of sociability. We describe the MySplitTime prototype which address these issues while retaining the active sociable nature of the spectating experience.