publications([{ "lang": "en", "bibtype": "article", "doi": "https://doi.org/10.1007/s00221-018-5368-2", "uri": "http://iihm.imag.fr/publication/CPB+18a/", "title": "Adaptation to visual feedback delays on touchscreens with hand vision", "url": "http://iihm.imag.fr/publs/2018/EBR18_Cattan_AdaptDelay.pdf", "journal": "Experimental Brain Research", "year": 2018, "number": 12, "pages": "3191–3201", "volume": 236, "id": 826, "abbr": "CPB+18a", "authors": { "1": { "first_name": "Élie", "last_name": "Cattan" }, "2": { "first_name": "Pascal", "last_name": "Perrier" }, "3": { "first_name": "François", "last_name": "Bérard" }, "4": { "first_name": "Silvain", "last_name": "Gerber" }, "5": { "first_name": "Amélie", "last_name": "Rochet-Capellan" } }, "date": "2018-09-06", "type": "Revues internationales avec comité de lecture", "abstract": "Direct touch finger interaction on a smartphone or a tablet is now ubiquitous. However, the latency inherent in digital computation produces an average feedback delay of ~75 ms between the action of the hand and its visible effect on digital content. This delay has been shown to affect users’ performance but it is unclear whether users adapt to this delay or whether it influences skill learning. Previous work studied adaptation to feedback delays but only for longer delays, with hidden hand or indirect devices. This paper addresses adaptation to touchscreen delay in two empirical studies involving the tracking of a target moving along an elliptical path. Participants were trained for the task either at the minimal delay the system allows (~9 ms) or at a longer delay equivalent to commercialized touch devices latencies (75 ms). After 10 training sessions over a minimum of two weeks (Experiment 1), participants adapt to the delay. They also display long-term retention seven weeks after the last training session. This adaptation generalized to a similar tracking path (e.g. infinity symbol). We also observed generalization of learning from the longer delay to the minimal delay condition (Experiment 2). The delay thus does not prevent the learning of tracking skill, which suggests that delay adaptation and tracking skill could be two separate components of learning.", "type_publi": "irevcomlec" }, { "lang": "en", "type_publi": "icolcomlec", "doi": "http://dx.doi.org/10.1145/3025453.3025585", "title": "Does Practice Make Perfect? Learning to Deal with Latency in Direct-Touch Interaction", "abstract": "Touch latency has been shown to deteriorate users' performances at levels as low as 25 ms, but this was tested only in short experimental sessions. Real life usage of touchscreens covers much longer periods. It provides training which could lead to reduce the impact of latency.\r\n\r\nWe investigate users' ability to compensate for touch latency with training. Two groups of participants were trained on a tracking task during ten different days over two weeks with either high or low latency. The gap of performances between the two groups, observed at the beginning of the experiment, was reduced by 54 % after training. Users can thus compensate for latency, at least partially. These results nuance the negative effects of touch latency reported in previous work. They suggest that long-term studies could provide better insights on users' behaviors when dealing with touch latency.", "authors": { "1": { "first_name": "Élie", "last_name": "Cattan" }, "2": { "first_name": "Amélie", "last_name": "Rochet-Capellan" }, "3": { "first_name": "Pascal", "last_name": "Perrier" }, "4": { "first_name": "François", "last_name": "Bérard" } }, "year": 2017, "uri": "http://iihm.imag.fr/publication/CRP+17a/", "pages": "5619-5629", "bibtype": "inproceedings", "id": 784, "abbr": "CRP+17a", "address": "Denver, USA", "date": "2017-05-30", "type": "Conférences internationales de large diffusion avec comité de lecture sur texte complet", "booktitle": "Proceedings of the 2017 CHI Conference on Human Factors in Computing Systems" }, { "lang": "en", "type_publi": "icolcomlec", "doi": "https://doi.org/10.1145/2817721.2817736", "title": "Reducing Latency with a Continuous Prediction: Effects on Users' Performance in Direct-Touch Target Acquisitions", "abstract": "Latency in direct-touch systems creates a spatial gap between the finger and the digital object when dragging. This breaks the illusion of presence, and has a negative effect on users' performances in common tasks such as target acquisitions. Latency can be reduced with faster hardware, but reaching imperceptible levels of latency with a hardware-only approach is a difficult challenge and an energy inefficient solution.\r\n\r\nWe studied the use of a continuous prediction of the touch location as an alternative to the hardware only approach to reduce the latency gap. We implemented a low latency touch surface and experimented with a constant speed linear prediction with various system latencies in the range [25ms-75ms]. We ran a user experiment to objectively assess the benefits of the prediction on users' performances in target acquisition tasks. Our study reveals that the prediction length is strongly constrained by the nature of target acquisition tasks, but that the approach can be successfully applied to counteract a large part of the negative effect of latency on users' performances.", "authors": { "1": { "first_name": "Élie", "last_name": "Cattan" }, "2": { "first_name": "Amélie", "last_name": "Rochet-Capellan" }, "3": { "first_name": "Pascal", "last_name": "Perrier" }, "4": { "first_name": "François", "last_name": "Bérard" } }, "year": 2015, "uri": "http://iihm.imag.fr/publication/CRP+15a/", "pages": "205-214", "bibtype": "inproceedings", "id": 742, "abbr": "CRP+15a", "address": "Madeira, Portugal", "date": "2015-11-16", "document": "http://iihm.imag.fr/publs/2015/ITS15_prediction.pdf", "type": "Conférences internationales de large diffusion avec comité de lecture sur texte complet", "booktitle": "Proceedings of the 2015 ACM International Conference on Interactive Tabletops and Surfaces" }]);