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    Multi-modal Experts Network for Autonomous Driving

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    End-to-end learning from sensory data has shown promising results in autonomous driving. While employing many sensors enhances world perception and should lead to more robust and reliable behavior of autonomous vehicles, it is challenging to train and deploy such network and at least two problems are encountered in the considered setting. The first one is the increase of computational complexity with the number of sensing devices. The other is the phenomena of network overfitting to the simplest and most informative input. We address both challenges with a novel, carefully tailored multi-modal experts network architecture and propose a multi-stage training procedure. The network contains a gating mechanism, which selects the most relevant input at each inference time step using a mixed discrete-continuous policy. We demonstrate the plausibility of the proposed approach on our 1/6 scale truck equipped with three cameras and one LiDAR.Comment: Published at the International Conference on Robotics and Automation (ICRA), 202

    ์˜๋ฏธ๋ก ์  ํ™˜๊ฒฝ ์ดํ•ด ๊ธฐ๋ฐ˜ ์ธ๊ฐ„ ๋กœ๋ด‡ ํ˜‘์—…

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    ํ•™์œ„๋…ผ๋ฌธ(๋ฐ•์‚ฌ)--์„œ์šธ๋Œ€ํ•™๊ต ๋Œ€ํ•™์› :๊ณต๊ณผ๋Œ€ํ•™ ์ „๊ธฐยท์ •๋ณด๊ณตํ•™๋ถ€,2020. 2. ์ด๋ฒ”ํฌ.Human-robot cooperation is unavoidable in various applications ranging from manufacturing to field robotics owing to the advantages of adaptability and high flexibility. Especially, complex task planning in large, unconstructed, and uncertain environments can employ the complementary capabilities of human and diverse robots. For a team to be effectives, knowledge regarding team goals and current situation needs to be effectively shared as they affect decision making. In this respect, semantic scene understanding in natural language is one of the most fundamental components for information sharing between humans and heterogeneous robots, as robots can perceive the surrounding environment in a form that both humans and other robots can understand. Moreover, natural-language-based scene understanding can reduce network congestion and improve the reliability of acquired data. Especially, in field robotics, transmission of raw sensor data increases network bandwidth and decreases quality of service. We can resolve this problem by transmitting information in the form of natural language that has encoded semantic representations of environments. In this dissertation, I introduce a human and heterogeneous robot cooperation scheme based on semantic scene understanding. I generate sentences and scene graphs, which is a natural language grounded graph over the detected objects and their relationships, with the graph map generated using a robot mapping algorithm. Subsequently, a framework that can utilize the results for cooperative mission planning of humans and robots is proposed. Experiments were performed to verify the effectiveness of the proposed methods. This dissertation comprises two parts: graph-based scene understanding and scene understanding based on the cooperation between human and heterogeneous robots. For the former, I introduce a novel natural language processing method using a semantic graph map. Although semantic graph maps have been widely applied to study the perceptual aspects of the environment, such maps do not find extensive application in natural language processing tasks. Several studies have been conducted on the understanding of workspace images in the field of computer vision; in these studies, the sentences were automatically generated, and therefore, multiple scenes have not yet been utilized for sentence generation. A graph-based convolutional neural network, which comprises spectral graph convolution and graph coarsening, and a recurrent neural network are employed to generate sentences attention over graphs. The proposed method outperforms the conventional methods on a publicly available dataset for single scenes and can be utilized for sequential scenes. Recently, deep learning has demonstrated impressive developments in scene understanding using natural language. However, it has not been extensively applied to high-level processes such as causal reasoning, analogical reasoning, or planning. The symbolic approach that calculates the sequence of appropriate actions by combining the available skills of agents outperforms in reasoning and planning; however, it does not entirely consider semantic knowledge acquisition for human-robot information sharing. An architecture that combines deep learning techniques and symbolic planner for human and heterogeneous robots to achieve a shared goal based on semantic scene understanding is proposed for scene understanding based on human-robot cooperation. In this study, graph-based perception is used for scene understanding. A planning domain definition language (PDDL) planner and JENA-TDB are utilized for mission planning and data acquisition storage, respectively. The effectiveness of the proposed method is verified in two situations: a mission failure, in which the dynamic environment changes, and object detection in a large and unseen environment.์ธ๊ฐ„๊ณผ ์ด์ข… ๋กœ๋ด‡ ๊ฐ„์˜ ํ˜‘์—…์€ ๋†’์€ ์œ ์—ฐ์„ฑ๊ณผ ์ ์‘๋ ฅ์„ ๋ณด์ผ ์ˆ˜ ์žˆ๋‹ค๋Š” ์ ์—์„œ ์ œ์กฐ์—…์—์„œ ํ•„๋“œ ๋กœ๋ณดํ‹ฑ์Šค๊นŒ์ง€ ๋‹ค์–‘ํ•œ ๋ถ„์•ผ์—์„œ ํ•„์—ฐ์ ์ด๋‹ค. ํŠนํžˆ, ์„œ๋กœ ๋‹ค๋ฅธ ๋Šฅ๋ ฅ์„ ์ง€๋‹Œ ๋กœ๋ด‡๋“ค๊ณผ ์ธ๊ฐ„์œผ๋กœ ๊ตฌ์„ฑ๋œ ํ•˜๋‚˜์˜ ํŒ€์€ ๋„“๊ณ  ์ •ํ˜•ํ™”๋˜์ง€ ์•Š์€ ๊ณต๊ฐ„์—์„œ ์„œ๋กœ์˜ ๋Šฅ๋ ฅ์„ ๋ณด์™„ํ•˜๋ฉฐ ๋ณต์žกํ•œ ์ž„๋ฌด ์ˆ˜ํ–‰์„ ๊ฐ€๋Šฅํ•˜๊ฒŒ ํ•œ๋‹ค๋Š” ์ ์—์„œ ํฐ ์žฅ์ ์„ ๊ฐ–๋Š”๋‹ค. ํšจ์œจ์ ์ธ ํ•œ ํŒ€์ด ๋˜๊ธฐ ์œ„ํ•ด์„œ๋Š”, ํŒ€์˜ ๊ณตํ†ต๋œ ๋ชฉํ‘œ ๋ฐ ๊ฐ ํŒ€์›์˜ ํ˜„์žฌ ์ƒํ™ฉ์— ๊ด€ํ•œ ์ •๋ณด๋ฅผ ์‹ค์‹œ๊ฐ„์œผ๋กœ ๊ณต์œ ํ•  ์ˆ˜ ์žˆ์–ด์•ผ ํ•˜๋ฉฐ ํ•จ๊ป˜ ์˜์‚ฌ ๊ฒฐ์ •์„ ํ•  ์ˆ˜ ์žˆ์–ด์•ผ ํ•œ๋‹ค. ์ด๋Ÿฌํ•œ ๊ด€์ ์—์„œ, ์ž์—ฐ์–ด๋ฅผ ํ†ตํ•œ ์˜๋ฏธ๋ก ์  ํ™˜๊ฒฝ ์ดํ•ด๋Š” ์ธ๊ฐ„๊ณผ ์„œ๋กœ ๋‹ค๋ฅธ ๋กœ๋ด‡๋“ค์ด ๋ชจ๋‘ ์ดํ•ดํ•  ์ˆ˜ ์žˆ๋Š” ํ˜•ํƒœ๋กœ ํ™˜๊ฒฝ์„ ์ธ์ง€ํ•œ๋‹ค๋Š” ์ ์—์„œ ๊ฐ€์žฅ ํ•„์ˆ˜์ ์ธ ์š”์†Œ์ด๋‹ค. ๋˜ํ•œ, ์šฐ๋ฆฌ๋Š” ์ž์—ฐ์–ด ๊ธฐ๋ฐ˜ ํ™˜๊ฒฝ ์ดํ•ด๋ฅผ ํ†ตํ•ด ๋„คํŠธ์›Œํฌ ํ˜ผ์žก์„ ํ”ผํ•จ์œผ๋กœ์จ ํš๋“ํ•œ ์ •๋ณด์˜ ์‹ ๋ขฐ์„ฑ์„ ๋†’์ผ ์ˆ˜ ์žˆ๋‹ค. ํŠนํžˆ, ๋Œ€๋Ÿ‰์˜ ์„ผ์„œ ๋ฐ์ดํ„ฐ ์ „์†ก์— ์˜ํ•ด ๋„คํŠธ์›Œํฌ ๋Œ€์—ญํญ์ด ์ฆ๊ฐ€ํ•˜๊ณ  ํ†ต์‹  QoS (Quality of Service) ์‹ ๋ขฐ๋„๊ฐ€ ๊ฐ์†Œํ•˜๋Š” ๋ฌธ์ œ๊ฐ€ ๋นˆ๋ฒˆํžˆ ๋ฐœ์ƒํ•˜๋Š” ํ•„๋“œ ๋กœ๋ณดํ‹ฑ์Šค ์˜์—ญ์—์„œ๋Š” ์˜๋ฏธ๋ก ์  ํ™˜๊ฒฝ ์ •๋ณด์ธ ์ž์—ฐ์–ด๋ฅผ ์ „์†กํ•จ์œผ๋กœ์จ ํ†ต์‹  ๋Œ€์—ญํญ์„ ๊ฐ์†Œ์‹œํ‚ค๊ณ  ํ†ต์‹  QoS ์‹ ๋ขฐ๋„๋ฅผ ์ฆ๊ฐ€์‹œํ‚ฌ ์ˆ˜ ์žˆ๋‹ค. ๋ณธ ํ•™์œ„ ๋…ผ๋ฌธ์—์„œ๋Š” ํ™˜๊ฒฝ์˜ ์˜๋ฏธ๋ก ์  ์ดํ•ด ๊ธฐ๋ฐ˜ ์ธ๊ฐ„ ๋กœ๋ด‡ ํ˜‘๋™ ๋ฐฉ๋ฒ•์— ๋Œ€ํ•ด ์†Œ๊ฐœํ•œ๋‹ค. ๋จผ์ €, ๋กœ๋ด‡์˜ ์ง€๋„ ์ž‘์„ฑ ์•Œ๊ณ ๋ฆฌ์ฆ˜์„ ํ†ตํ•ด ํš๋“ํ•œ ๊ทธ๋ž˜ํ”„ ์ง€๋„๋ฅผ ์ด์šฉํ•˜์—ฌ ์ž์—ฐ์–ด ๋ฌธ์žฅ๊ณผ ๊ฒ€์ถœํ•œ ๊ฐ์ฒด ๋ฐ ๊ฐ ๊ฐ์ฒด ๊ฐ„์˜ ๊ด€๊ณ„๋ฅผ ์ž์—ฐ์–ด ๋‹จ์–ด๋กœ ํ‘œํ˜„ํ•˜๋Š” ๊ทธ๋ž˜ํ”„๋ฅผ ์ƒ์„ฑํ•œ๋‹ค. ๊ทธ๋ฆฌ๊ณ  ์ž์—ฐ์–ด ์ฒ˜๋ฆฌ ๊ฒฐ๊ณผ๋ฅผ ์ด์šฉํ•˜์—ฌ ์ธ๊ฐ„๊ณผ ๋‹ค์–‘ํ•œ ๋กœ๋ด‡๋“ค์ด ํ•จ๊ป˜ ํ˜‘์—…ํ•˜์—ฌ ์ž„๋ฌด๋ฅผ ์ˆ˜ํ–‰ํ•  ์ˆ˜ ์žˆ๋„๋ก ํ•˜๋Š” ํ”„๋ ˆ์ž„์›Œํฌ๋ฅผ ์ œ์•ˆํ•œ๋‹ค. ๋ณธ ํ•™์œ„ ๋…ผ๋ฌธ์€ ํฌ๊ฒŒ ๊ทธ๋ž˜ํ”„๋ฅผ ์ด์šฉํ•œ ์˜๋ฏธ๋ก ์  ํ™˜๊ฒฝ ์ดํ•ด์™€ ์˜๋ฏธ๋ก ์  ํ™˜๊ฒฝ ์ดํ•ด๋ฅผ ํ†ตํ•œ ์ธ๊ฐ„๊ณผ ์ด์ข… ๋กœ๋ด‡ ๊ฐ„์˜ ํ˜‘์—… ๋ฐฉ๋ฒ•์œผ๋กœ ๊ตฌ์„ฑ๋œ๋‹ค. ๋จผ์ €, ๊ทธ๋ž˜ํ”„๋ฅผ ์ด์šฉํ•œ ์˜๋ฏธ๋ก ์  ํ™˜๊ฒฝ ์ดํ•ด ๋ถ€๋ถ„์—์„œ๋Š” ์˜๋ฏธ๋ก ์  ๊ทธ๋ž˜ํ”„ ์ง€๋„๋ฅผ ์ด์šฉํ•œ ์ƒˆ๋กœ์šด ์ž์—ฐ์–ด ์ฒ˜๋ฆฌ ๋ฐฉ๋ฒ•์— ๋Œ€ํ•ด ์†Œ๊ฐœํ•œ๋‹ค. ์˜๋ฏธ๋ก ์  ๊ทธ๋ž˜ํ”„ ์ง€๋„ ์ž‘์„ฑ ๋ฐฉ๋ฒ•์€ ๋กœ๋ด‡์˜ ํ™˜๊ฒฝ ์ธ์ง€ ์ธก๋ฉด์—์„œ ๋งŽ์ด ์—ฐ๊ตฌ๋˜์—ˆ์ง€๋งŒ ์ด๋ฅผ ์ด์šฉํ•œ ์ž์—ฐ์–ด ์ฒ˜๋ฆฌ ๋ฐฉ๋ฒ•์€ ๊ฑฐ์˜ ์—ฐ๊ตฌ๋˜์ง€ ์•Š์•˜๋‹ค. ๋ฐ˜๋ฉด ์ปดํ“จํ„ฐ ๋น„์ „ ๋ถ„์•ผ์—์„œ๋Š” ์ด๋ฏธ์ง€๋ฅผ ์ด์šฉํ•œ ํ™˜๊ฒฝ ์ดํ•ด ์—ฐ๊ตฌ๊ฐ€ ๋งŽ์ด ์ด๋ฃจ์–ด์กŒ์ง€๋งŒ, ์—ฐ์†์ ์ธ ์žฅ๋ฉด๋“ค์€ ๋‹ค๋ฃจ๋Š”๋ฐ๋Š” ํ•œ๊ณ„์ ์ด ์žˆ๋‹ค. ๋”ฐ๋ผ์„œ ์šฐ๋ฆฌ๋Š” ๊ทธ๋ž˜ํ”„ ์ŠคํŽ™ํŠธ๋Ÿผ ์ด๋ก ์— ๊ธฐ๋ฐ˜ํ•œ ๊ทธ๋ž˜ํ”„ ์ปจ๋ณผ๋ฃจ์…˜๊ณผ ๊ทธ๋ž˜ํ”„ ์ถ•์†Œ ๋ ˆ์ด์–ด๋กœ ๊ตฌ์„ฑ๋œ ๊ทธ๋ž˜ํ”„ ์ปจ๋ณผ๋ฃจ์…˜ ์‹ ๊ฒฝ๋ง ๋ฐ ์ˆœํ™˜ ์‹ ๊ฒฝ๋ง์„ ์ด์šฉํ•˜์—ฌ ๊ทธ๋ž˜ํ”„๋ฅผ ์„ค๋ช…ํ•˜๋Š” ๋ฌธ์žฅ์„ ์ƒ์„ฑํ•œ๋‹ค. ์ œ์•ˆํ•œ ๋ฐฉ๋ฒ•์€ ๊ธฐ์กด์˜ ๋ฐฉ๋ฒ•๋“ค๋ณด๋‹ค ํ•œ ์žฅ๋ฉด์— ๋Œ€ํ•ด ํ–ฅ์ƒ๋œ ์„ฑ๋Šฅ์„ ๋ณด์˜€์œผ๋ฉฐ ์—ฐ์†๋œ ์žฅ๋ฉด๋“ค์— ๋Œ€ํ•ด์„œ๋„ ์„ฑ๊ณต์ ์œผ๋กœ ์ž์—ฐ์–ด ๋ฌธ์žฅ์„ ์ƒ์„ฑํ•œ๋‹ค. ์ตœ๊ทผ ๋”ฅ๋Ÿฌ๋‹์€ ์ž์—ฐ์–ด ๊ธฐ๋ฐ˜ ํ™˜๊ฒฝ ์ธ์ง€์— ์žˆ์–ด ๊ธ‰์†๋„๋กœ ํฐ ๋ฐœ์ „์„ ์ด๋ฃจ์—ˆ๋‹ค. ํ•˜์ง€๋งŒ ์ธ๊ณผ ์ถ”๋ก , ์œ ์ถ”์  ์ถ”๋ก , ์ž„๋ฌด ๊ณ„ํš๊ณผ ๊ฐ™์€ ๋†’์€ ์ˆ˜์ค€์˜ ํ”„๋กœ์„ธ์Šค์—๋Š” ์ ์šฉ์ด ํž˜๋“ค๋‹ค. ๋ฐ˜๋ฉด ์ž„๋ฌด๋ฅผ ์ˆ˜ํ–‰ํ•˜๋Š” ๋ฐ ์žˆ์–ด ๊ฐ ์—์ด์ „ํŠธ์˜ ๋Šฅ๋ ฅ์— ๋งž๊ฒŒ ํ–‰์œ„๋“ค์˜ ์ˆœ์„œ๋ฅผ ๊ณ„์‚ฐํ•ด์ฃผ๋Š” ์ƒ์ง•์  ์ ‘๊ทผ๋ฒ•(symbolic approach)์€ ์ถ”๋ก ๊ณผ ์ž„๋ฌด ๊ณ„ํš์— ์žˆ์–ด ๋›ฐ์–ด๋‚œ ์„ฑ๋Šฅ์„ ๋ณด์ด์ง€๋งŒ ์ธ๊ฐ„๊ณผ ๋กœ๋ด‡๋“ค ์‚ฌ์ด์˜ ์˜๋ฏธ๋ก ์  ์ •๋ณด ๊ณต์œ  ๋ฐฉ๋ฒ•์— ๋Œ€ํ•ด์„œ๋Š” ๊ฑฐ์˜ ๋‹ค๋ฃจ์ง€ ์•Š๋Š”๋‹ค. ๋”ฐ๋ผ์„œ, ์ธ๊ฐ„๊ณผ ์ด์ข… ๋กœ๋ด‡ ๊ฐ„์˜ ํ˜‘์—… ๋ฐฉ๋ฒ• ๋ถ€๋ถ„์—์„œ๋Š” ๋”ฅ๋Ÿฌ๋‹ ๊ธฐ๋ฒ•๋“ค๊ณผ ์ƒ์ง•์  ํ”Œ๋ž˜๋„ˆ(symbolic planner)๋ฅผ ์—ฐ๊ฒฐํ•˜๋Š” ํ”„๋ ˆ์ž„์›Œํฌ๋ฅผ ์ œ์•ˆํ•˜์—ฌ ์˜๋ฏธ๋ก ์  ์ดํ•ด๋ฅผ ํ†ตํ•œ ์ธ๊ฐ„ ๋ฐ ์ด์ข… ๋กœ๋ด‡ ๊ฐ„์˜ ํ˜‘์—…์„ ๊ฐ€๋Šฅํ•˜๊ฒŒ ํ•œ๋‹ค. ์šฐ๋ฆฌ๋Š” ์˜๋ฏธ๋ก ์  ์ฃผ๋ณ€ ํ™˜๊ฒฝ ์ดํ•ด๋ฅผ ์œ„ํ•ด ์ด์ „ ๋ถ€๋ถ„์—์„œ ์ œ์•ˆํ•œ ๊ทธ๋ž˜ํ”„ ๊ธฐ๋ฐ˜ ์ž์—ฐ์–ด ๋ฌธ์žฅ ์ƒ์„ฑ์„ ์ˆ˜ํ–‰ํ•œ๋‹ค. PDDL ํ”Œ๋ž˜๋„ˆ์™€ JENA-TDB๋Š” ๊ฐ๊ฐ ์ž„๋ฌด ๊ณ„ํš ๋ฐ ์ •๋ณด ํš๋“ ์ €์žฅ์†Œ๋กœ ์‚ฌ์šฉํ•œ๋‹ค. ์ œ์•ˆํ•œ ๋ฐฉ๋ฒ•์˜ ํšจ์šฉ์„ฑ์€ ์‹œ๋ฎฌ๋ ˆ์ด์…˜์„ ํ†ตํ•ด ๋‘ ๊ฐ€์ง€ ์ƒํ™ฉ์— ๋Œ€ํ•ด์„œ ๊ฒ€์ฆํ•œ๋‹ค. ํ•˜๋‚˜๋Š” ๋™์  ํ™˜๊ฒฝ์—์„œ ์ž„๋ฌด ์‹คํŒจ ์ƒํ™ฉ์ด๋ฉฐ ๋‹ค๋ฅธ ํ•˜๋‚˜๋Š” ๋„“์€ ๊ณต๊ฐ„์—์„œ ๊ฐ์ฒด๋ฅผ ์ฐพ๋Š” ์ƒํ™ฉ์ด๋‹ค.1 Introduction 1 1.1 Background and Motivation 1 1.2 Literature Review 5 1.2.1 Natural Language-Based Human-Robot Cooperation 5 1.2.2 Artificial Intelligence Planning 5 1.3 The Problem Statement 10 1.4 Contributions 11 1.5 Dissertation Outline 12 2 Natural Language-Based Scene Graph Generation 14 2.1 Introduction 14 2.2 Related Work 16 2.3 Scene Graph Generation 18 2.3.1 Graph Construction 19 2.3.2 Graph Inference 19 2.4 Experiments 22 2.5 Summary 25 3 Language Description with 3D Semantic Graph 26 3.1 Introduction 26 3.2 Related Work 26 3.3 Natural Language Description 29 3.3.1 Preprocess 29 3.3.2 Graph Feature Extraction 33 3.3.3 Natural Language Description with Graph Features 34 3.4 Experiments 35 3.5 Summary 42 4 Natural Question with Semantic Graph 43 4.1 Introduction 43 4.2 Related Work 45 4.3 Natural Question Generation 47 4.3.1 Preprocess 49 4.3.2 Graph Feature Extraction 50 4.3.3 Natural Question with Graph Features 51 4.4 Experiments 52 4.5 Summary 58 5 PDDL Planning with Natural Language 59 5.1 Introduction 59 5.2 Related Work 60 5.3 PDDL Planning with Incomplete World Knowledge 61 5.3.1 Natural Language Process for PDDL Planning 63 5.3.2 PDDL Planning System 64 5.4 Experiments 65 5.5 Summary 69 6 PDDL Planning with Natural Language-Based Scene Understanding 70 6.1 Introduction 70 6.2 Related Work 74 6.3 A Framework for Heterogeneous Multi-Agent Cooperation 77 6.3.1 Natural Language-Based Cognition 78 6.3.2 Knowledge Engine 80 6.3.3 PDDL Planning Agent 81 6.4 Experiments 82 6.4.1 Experiment Setting 82 6.4.2 Scenario 84 6.4.3 Results 87 6.5 Summary 91 7 Conclusion 92Docto

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    This work considers the problem of planning and control of robots in an environment with obstacles and external disturbances. The safety of robots is harder to achieve when planning in such uncertain environments. We describe a robust control scheme that combines three key components: system identification, uncertainty propagation, and trajectory optimization. Using this control scheme we tackle three problems. First, we develop a Nonlinear Model Predictive Controller (NMPC) for articulated rigid bodies and apply it to an aerial manipulation system to grasp object mid-air. Next, we tackle the problem of obstacle avoidance under unknown external disturbances. We propose two approaches, the first approach using adaptive NMPC with open- loop uncertainty propagation and the second approach using Tube NMPC. After that, we introduce dynamic models which use Artificial Neural Networks (ANN) and combine them with NMPC to control a ground vehicle and an aerial manipulation system. Finally, we introduce a software framework for integrating the above algorithms to perform complex tasks. The software framework provides users with the ability to design systems that are robust to control and hardware failures where preventive action is taken before-hand. The framework also allows for safe testing of control and task logic in simulation before evaluating on the real robot. The software framework is applied to an aerial manipulation system to perform a package sorting task, and extensive experiments demonstrate the ability of the system to recover from failures. In addition to robust control, we present two related control problems. The first problem pertains to designing an obstacle avoidance controller for an underactuated system that is Lyapunov stable. We extend a standard gyroscopic obstacle avoidance controller to be applicable to an underactuated system. The second problem addresses the navigation of an Unmanned Ground Vehicle (UGV) on an unstructured terrain. We propose using NMPC combined with a high fidelity physics engine to generate a reference trajectory that is dynamically feasible and accounts for unsafe areas in the terrain

    Fruit Detection and Tree Segmentation for Yield Mapping in Orchards

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    Accurate information gathering and processing is critical for precision horticulture, as growers aim to optimise their farm management practices. An accurate inventory of the crop that details its spatial distribution along with health and maturity, can help farmers efficiently target processes such as chemical and fertiliser spraying, crop thinning, harvest management, labour planning and marketing. Growers have traditionally obtained this information by using manual sampling techniques, which tend to be labour intensive, spatially sparse, expensive, inaccurate and prone to subjective biases. Recent advances in sensing and automation for field robotics allow for key measurements to be made for individual plants throughout an orchard in a timely and accurate manner. Farmer operated machines or unmanned robotic platforms can be equipped with a range of sensors to capture a detailed representation over large areas. Robust and accurate data processing techniques are therefore required to extract high level information needed by the grower to support precision farming. This thesis focuses on yield mapping in orchards using image and light detection and ranging (LiDAR) data captured using an unmanned ground vehicle (UGV). The contribution is the framework and algorithmic components for orchard mapping and yield estimation that is applicable to different fruit types and orchard configurations. The framework includes detection of fruits in individual images and tracking them over subsequent frames. The fruit counts are then associated to individual trees, which are segmented from image and LiDAR data, resulting in a structured spatial representation of yield. The first contribution of this thesis is the development of a generic and robust fruit detection algorithm. Images captured in the outdoor environment are susceptible to highly variable external factors that lead to significant appearance variations. Specifically in orchards, variability is caused by changes in illumination, target pose, tree types, etc. The proposed techniques address these issues by using state-of-the-art feature learning approaches for image classification, while investigating the utility of orchard domain knowledge for fruit detection. Detection is performed using both pixel-wise classification of images followed instance segmentation, and bounding-box regression approaches. The experimental results illustrate the versatility of complex deep learning approaches over a multitude of fruit types. The second contribution of this thesis is a tree segmentation approach to detect the individual trees that serve as a standard unit for structured orchard information systems. The work focuses on trellised trees, which present unique challenges for segmentation algorithms due to their intertwined nature. LiDAR data are used to segment the trellis face, and to generate proposals for individual trees trunks. Additional trunk proposals are provided using pixel-wise classification of the image data. The multi-modal observations are fine-tuned by modelling trunk locations using a hidden semi-Markov model (HSMM), within which prior knowledge of tree spacing is incorporated. The final component of this thesis addresses the visual occlusion of fruit within geometrically complex canopies by using a multi-view detection and tracking approach. Single image fruit detections are tracked over a sequence of images, and associated to individual trees or farm rows, with the spatial distribution of the fruit counting forming a yield map over the farm. The results show the advantage of using multi-view imagery (instead of single view analysis) for fruit counting and yield mapping. This thesis includes extensive experimentation in almond, apple and mango orchards, with data captured by a UGV spanning a total of 5 hectares of farm area, over 30 km of vehicle traversal and more than 7,000 trees. The validation of the different processes is performed using manual annotations, which includes fruit and tree locations in image and LiDAR data respectively. Additional evaluation of yield mapping is performed by comparison against fruit counts on trees at the farm and counts made by the growers post-harvest. The framework developed in this thesis is demonstrated to be accurate compared to ground truth at all scales of the pipeline, including fruit detection and tree mapping, leading to accurate yield estimation, per tree and per row, for the different crops. Through the multitude of field experiments conducted over multiple seasons and years, the thesis presents key practical insights necessary for commercial development of an information gathering system in orchards

    On the Modeling of Dynamic-Systems using Sequence-based Deep Neural-Networks

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    The objective of this thesis is the adaptation and development of sequence-based Neural-Networks (NNs) applied to the modeling of dynamic systems. More specifically, we will focus our study on 2 sub-problems: the modeling of time-series, the modeling and control of multiple-input multiple-output (MIMO) systems. These 2 sub-problems will be explored through the modeling of crops, and the modeling and control of robots. To solve these problems, we build on NNs and training schemes allowing our models to out-perform the state-of-the-art results in their respective fields. In the irrigation field, we show that NNs are powerful tools capable of modeling the water consumption of crops while observing only a portion of what is currently required by reference methods. We further demonstrate the potential of NNs by inferring irrigation recommendations in real-time. In robotics, we show that prioritization techniques can be used to learn better robot dynamic models. We apply the models learned using these methods inside an Model Predictive Control (MPC) controller, further demonstrating their benefits. Additionally, we leverage Dreamer, an Model Based Reinforcement Learning (MBRL) agent, to solve visuomotor tasks. We demonstrate that MBRL controllers can be used for sensor-based control on real robots without being trained on real systems. Adding to this result, we developed a physics-guided variant of DREAMER. This variation of the original algorithm is more flexible and designed for mobile robots. This novel framework enables reusing previously learned dynamics and transferring environment knowledge to other robots. Furthermore, using this new model, we train agents to reach various goals without interacting with the system. This increases the reusability of the learned models and makes for a highly data-efficient learning scheme. Moreover, this allows for efficient dynamics randomization, creating robust agents that transfer well to unseen dynamics.Ph.D

    Beyond sight : an approach for visual semantic navigation of mobile robots in an indoor environment

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    Orientador: Eduardo TodtDissertaรงรฃo (mestrado) - Universidade Federal do Paranรก, Setor de Ciรชncias Exatas, Programa de Pรณs-Graduaรงรฃo em Informรกtica. Defesa : Curitiba, 22/02/2021Inclui referรชncias: p. 134-146รrea de concentraรงรฃo: Ciรชncia da ComputaรงรฃoResumo: Com o crescimento da automacao, os veiculos nao tripulados tornaram-se um tema de destaque, tanto como produtos comerciais quanto como um topico de pesquisa cientifica. Compoem um campo multidisciplinar de robotica que abrange sistemas embarcados, teoria de controle, planejamento de caminhos, localizacao e mapeamento simultaneos (SLAM), reconstrucao de cenas e reconhecimento de padroes. Apresentamos neste trabalho uma pesquisa exploratoria de como a fusao dos dados de sensores e algoritmos de aprendizagem de maquinas, que compoem o estado da arte, podem realizar a tarefa chamada Navegacao Visual Semantica que e uma navegacao autonoma utilizando observacoes visuais egocentricas para alcancar um objeto pertencente a classe semantica alvo sem conhecimento previo do ambiente. Para realizar experimentos, propomos uma encarnacao chamada VRIBot. O robo foi modelado de tal forma que pode ser facilmente simulado, e os experimentos sao reproduziveis sem a necessidade do robo fisico. Tres diferentes pipelines EXchangeable, AUTOcrat e BEyond foram propostos e avaliados. Nossa abordagem chamada BEyond alcancou a 5a posicao entre 12 no conjunto val_mini do Habitat-Challenge 2020 ObjectNav quando comparada a outros resultados relatados na tabela classificativa da competicao. O resultado da pesquisa mostra que a fusao de dados em conjunto com algoritmos de aprendizado de maquina sao uma abordagem promissora para o problema de navegacao semantica. Palavras-chave: Navegacao-visual-semantica. SLAM. Aprendizado-profundo. Navegacao- Autonoma. Segmentacao-semantica.Abstract: With the rise of automation, unmanned vehicles became a hot topic both as commercial products and as a scientific research topic. It composes a multi-disciplinary field of robotics that encompasses embedded systems, control theory, path planning, Simultaneous Localization and Mapping (SLAM), scene reconstruction, and pattern recognition. In this work, we present our exploratory research of how sensor data fusion and state-of-the-art machine learning algorithms can perform the Embodied Artificial Intelligence (E-AI) task called Visual Semantic Navigation, a.k.a Object-Goal Navigation (ObjectNav) that is an autonomous navigation using egocentric visual observations to reach an object belonging to the target semantic class without prior knowledge of the environment. To perform experimentation, we propose an embodiment named VRIBot. The robot was modeled in such a way that it can be easily simulated, and the experiments are reproducible without the need for the physical robot. Three different pipelines EXchangeable, AUTOcrat, and BEyond, were proposed and evaluated. Our approach, named BEyond, reached 5th rank out of 12 on the val_mini set of the Habitat-Challenge 2020 ObjectNav when compared to other reported results on the competition's leaderboard. Our results show that data fusion combined with machine learning algorithms are a promising approach to the semantic navigation problem. Keywords: Visual-semantic-navigation. Deep-Learning. SLAM. Autonomous-navigation. Semantic-segmentation

    Collision Avoidance on Unmanned Aerial Vehicles using Deep Neural Networks

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    Unmanned Aerial Vehicles (UAVs), although hardly a new technology, have recently gained a prominent role in many industries, being widely used not only among enthusiastic consumers but also in high demanding professional situations, and will have a massive societal impact over the coming years. However, the operation of UAVs is full of serious safety risks, such as collisions with dynamic obstacles (birds, other UAVs, or randomly thrown objects). These collision scenarios are complex to analyze in real-time, sometimes being computationally impossible to solve with existing State of the Art (SoA) algorithms, making the use of UAVs an operational hazard and therefore significantly reducing their commercial applicability in urban environments. In this work, a conceptual framework for both stand-alone and swarm (networked) UAVs is introduced, focusing on the architectural requirements of the collision avoidance subsystem to achieve acceptable levels of safety and reliability. First, the SoA principles for collision avoidance against stationary objects are reviewed. Afterward, a novel image processing approach that uses deep learning and optical flow is presented. This approach is capable of detecting and generating escape trajectories against potential collisions with dynamic objects. Finally, novel models and algorithms combinations were tested, providing a new approach for the collision avoidance of UAVs using Deep Neural Networks. The feasibility of the proposed approach was demonstrated through experimental tests using a UAV, created from scratch using the framework developed.Os veรญculos aรฉreos nรฃo tripulados (VANTs), embora dificilmente considerados uma nova tecnologia, ganharam recentemente um papel de destaque em muitas indรบstrias, sendo amplamente utilizados nรฃo apenas por amadores, mas tambรฉm em situaรงรตes profissionais de alta exigรชncia, sendo expectรกvel um impacto social massivo nos prรณximos anos. No entanto, a operaรงรฃo de VANTs estรก repleta de sรฉrios riscos de seguranรงa, como colisรตes com obstรกculos dinรขmicos (pรกssaros, outros VANTs ou objetos arremessados). Estes cenรกrios de colisรฃo sรฃo complexos para analisar em tempo real, ร s vezes sendo computacionalmente impossรญvel de resolver com os algoritmos existentes, tornando o uso de VANTs um risco operacional e, portanto, reduzindo significativamente a sua aplicabilidade comercial em ambientes citadinos. Neste trabalho, uma arquitectura conceptual para VANTs autรดnomos e em rede รฉ apresentada, com foco nos requisitos arquitetรดnicos do subsistema de prevenรงรฃo de colisรฃo para atingir nรญveis aceitรกveis de seguranรงa e confiabilidade. Os estudos presentes na literatura para prevenรงรฃo de colisรฃo contra objectos estacionรกrios sรฃo revistos e uma nova abordagem รฉ descrita. Esta tecnica usa tรฉcnicas de aprendizagem profunda e processamento de imagem, para realizar a prevenรงรฃo de colisรตes em tempo real com objetos mรณveis. Por fim, novos modelos e combinaรงรตes de algoritmos sรฃo propostos, fornecendo uma nova abordagem para evitar colisรตes de VANTs usando Redes Neurais Profundas. A viabilidade da abordagem foi demonstrada atravรฉs de testes experimentais utilizando um VANT, desenvolvido a partir da arquitectura apresentada

    Proceedings of the 9th Conference on Autonomous Robot Systems and Competitions

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    Welcome to ROBOTICA 2009. This is the 9th edition of the conference on Autonomous Robot Systems and Competitions, the third time with IEEEโ€Robotics and Automation Society Technical Coโ€Sponsorship. Previous editions were held since 2001 in Guimaraฬƒes, Aveiro, Porto, Lisboa, Coimbra and Algarve. ROBOTICA 2009 is held on the 7th May, 2009, in Castelo Branco , Portugal. ROBOTICA has received 32 paper submissions, from 10 countries, in South America, Asia and Europe. To evaluate each submission, three reviews by paper were performed by the international program committee. 23 papers were published in the proceedings and presented at the conference. Of these, 14 papers were selected for oral presentation and 9 papers were selected for poster presentation. The global acceptance ratio was 72%. After the conference, eighth papers will be published in the Portuguese journal Roboฬtica, and the best student paper will be published in IEEE Multidisciplinary Engineering Education Magazine. Three prizes will be awarded in the conference for: the best conference paper, the best student paper and the best presentation. The last two, sponsored by the IEEE Education Society โ€ Student Activities Committee. We would like to express our thanks to all participants. First of all to the authors, whose quality work is the essence of this conference. Next, to all the members of the international program committee and reviewers, who helped us with their expertise and valuable time. We would also like to deeply thank the invited speaker, Jean Paul Laumond, LAASโ€CNRS France, for their excellent contribution in the field of humanoid robots. Finally, a word of appreciation for the hard work of the secretariat and volunteers. Our deep gratitude goes to the Scientific Organisations that kindly agreed to sponsor the Conference, and made it come true. We look forward to seeing more results of R&D work on Robotics at ROBOTICA 2010, somewhere in Portugal

    Advances in Automated Driving Systems

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    Electrification, automation of vehicle control, digitalization and new mobility are the mega-trends in automotive engineering, and they are strongly connected. While many demonstrations for highly automated vehicles have been made worldwide, many challenges remain in bringing automated vehicles to the market for private and commercial use. The main challenges are as follows: reliable machine perception; accepted standards for vehicle-type approval and homologation; verification and validation of the functional safety, especially at SAE level 3+ systems; legal and ethical implications; acceptance of vehicle automation by occupants and society; interaction between automated and human-controlled vehicles in mixed traffic; humanโ€“machine interaction and usability; manipulation, misuse and cyber-security; the system costs of hard- and software and development efforts. This Special Issue was prepared in the years 2021 and 2022 and includes 15 papers with original research related to recent advances in the aforementioned challenges. The topics of this Special Issue cover: Machine perception for SAE L3+ driving automation; Trajectory planning and decision-making in complex traffic situations; X-by-Wire system components; Verification and validation of SAE L3+ systems; Misuse, manipulation and cybersecurity; Humanโ€“machine interactions, driver monitoring and driver-intention recognition; Road infrastructure measures for the introduction of SAE L3+ systems; Solutions for interactions between human- and machine-controlled vehicles in mixed traffic
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