Sistem Kontrol Inverted Pendulum Pada Balancing Mobile Robot

Sistem kontrol merupakan suatu sistem yang menjadi pusat perhatian di bidang robotika. Dengan adanya sistem kontrol ini, robot bisa menjadi lebih cerdas dan canggih. Robot berpendulum ini akan berusaha menyetimbangkan sistemnya agar pendulum tetap tegak 900. Sebagai deteksi kemiringan antara robot dengan lantai digunakan sensor Sharp GP2D12 yang menghasilkan output tegangan analog. Data dari sensor ini akan diolah oleh Mikrokontroler ATMega 16, karena data yang dibawa oleh Sharp GP2D12 ini mempunyai noise, maka data harus difilter. Filter yang dipakai adalah Single Exponential Filtering yang bisa mereduksi noise secara optimal disamping juga mempunyai respon waktu yang cepat. Setelah selesai pemrosesan, hasil filter akan diolah dengan kontrol PID. Dengan sistem kontrol ini, robot mempunyai respon yang cepat untuk bergerak maju mundur searah dengan arah gerak jatuhnya pendulum. Prosentasi sistem keberhasilan PID ini adalah 90%

Pengendalian Robot Lengan Beroda Dengan Kamera Untuk Aplikasi Pengambilan Obyek

Penggunaan robot dalam kehidupan manusia semakin bertambah tiap tahunnya, hal ini karena penggunaan robot dapat membantu meringankan pekerjaan manusia. Dalam proyek akhir ini akan dikembangkan robot mobile yang dapat melakukan tugas yang diberikan, yakni mampu mengambil obyek yang telah ditentukan, penggunaan pengolahan citra juga semakin berkembang dalam teknologi komputerisasi dan juga sangat membantu dalam menyelesaikan tugas manusia, bahkan terkadang sangat sulit dilakukan manusia. Penggunaan dua metode pendeteksian obyek dapat mendukung dari sistim ini untuk menyelesaikan tugas yang diberikan, template metching yang digunakan untuk pendeteksian obyek yang telah dipilih, dan viola-jones yang digunakan sebagai bantuan untuk mendapatkan hasil yang maksimal. Hasil pendeteksian yang digunakan untuk tracking mencapai 90%, pada rencana pengembangan kedepanya diharapkan munculnya suatu robot yang menerapkan pengolahan citra, untuk diaplikasikan pada kehidupan sehari-hari

Pengendalian Posisi Mobile Robot Menggunakan Metode Neural Network dengan Umpan Balik Kamera Pemosisian Global

Pengembangan teknik otomasi pergerakan robot untuk dapat beroperasi di dunia nyata sudah menjadi bahan penelitian bagi pengembangan mobile robot di dunia saat ini. Untuk dapat mencapai suatu posisi yang diinginkan dari posisi awal, mobile robot membutuhkan suatu sistem navigasi yang dapat mengarahkan mobile robot tersebut ke posisi yang diinginkan. Untuk itu peneliti membuat sistem pengendali robot menggunakan metode neural network dengan menggunakan umpan balik kamera. Kamera berfungsi sebagai pemantau pergerakan robot yang nantinya akan diumpan balikkan ke dalam PC untuk mengetahui jalur yang harus ditempuh oleh robot dan posisi robot. Neural network digunakan untuk kontrol posisi pergerakan robot, fase learning neural network dilakukan secara offline (didalam PC) sedangkan fase mapping (penggunaan) dilakukan pada mikrokontroler yang terdapat pada robot. Data yang akan diajarkan dalam proses learning adalah data error sudut dan nilai PWM motor kanan dan PWM motor kiri. Persen keberhasilan dalam pengenalan data yang diajarkan adalah 95%. Sedangkan persen keberhasilan untuk pengontrolan robot menggunakan metode neural network backpropagation adalah 70%

Reproducibility of preclinical animal research improves with heterogeneity of study samples

Single-laboratory studies conducted under highly standardized conditions are the gold standard in preclinical animal research. Using simulations based on 440 preclinical studies across 13 different interventions in animal models of stroke, myocardial infarction, and breast cancer, we compared the accuracy of effect size estimates between single-laboratory and multi-laboratory study designs. Single-laboratory studies generally failed to predict effect size accurately, and larger sample sizes rendered effect size estimates even less accurate. By contrast, multi-laboratory designs including as few as 2 to 4 laboratories increased coverage probability by up to 42 percentage points without a need for larger sample sizes. These findings demonstrate that within-study standardization is a major cause of poor reproducibility. More representative study samples are required to improve the external validity and reproducibility of preclinical animal research and to prevent wasting animals and resources for inconclusive research

The physiological responses of cacao to the environment and the implications for climate change resilience. A review

Cacao (Theobroma cacao L.) is a tropical perennial crop which is of great economic importance to the confectionary industry and to the economies of many countries of the humid tropics where it is grown. Some recent studies have suggested climate change could severely impact cacao production in West Africa. It is essential to incorporate our understanding of the physiology and genetic variation within cacao germplasm when discussing the implications of climate change on cacao productivity and developing strategies for climate resilience in cacao production. Here we review the current research on the physiological responses of cacao to various climate factors. Our main findings are 1) water limitation causes significant yield reduction in cacao but genotypic variation in sensitivity is evident, 2) in the field cacao experiences higher temperatures than is often reported in the literature, 3) the complexity of the cacao/ shade tree interaction can lead to contradictory results, 4) elevated CO2 may alleviate some negative effects of climate change 5) implementation of mitigation strategies can help reduce environmental stress, 6) significant gaps in the research need addressing to accelerate the development of climate resilience. Harnessing the significant genetic variation apparent within cacao germplasm is essential to develop modern varieties capable of high yields in non-optimal conditions. Mitigation strategies will also be essential but to use shading to best effect shade tree selection is crucial to avoid resource competition. Cacao is often described as being sensitive to climate change but genetic variation, adaptive responses, appropriate mitigation strategies and interactive climate effects should all be considered when predicting the future of cacao production. Incorporating these physiological responses to various environmental conditions and developing a deeper understanding of the processes underlying these responses will help to accelerate the development of a more resource use efficient tree ensuring sustainable production into the future

Response of Quercus ilex seedlings to Phytophthora spp. root infection in a soil infestation test

[EN] Phytophthora species are the main agents associated with oak (Quercus spp.) decline, together with the changing environmental conditions and the intensive land use. The aim of this study was to evaluate the susceptibility of Quercus ilex to the inoculation with eight Phytophthora species. Seven to eight month old Q. ilex seedlings grown from acorns, obtained from two Spanish origins, were inoculated with P. cinnamomi, P. cryptogea, P. gonapodyides, P. megasperma, P. nicotianae, P. plurivora, P. psychrophila and P. quercina. All Phytophthora inoculated seedlings showed decline and symptoms including small dark necrotic root lesions, root cankers, and loss of fine roots and tap root. The most aggressive species were P. cinnamomi, P. cryptogea, P. gonapodyides, P. plurivora and P. psychrophila followed by P. megasperma., while Phytophthora quercina and P. nicotianae were the less aggressive species. Results obtained confirm that these Phytophthora species could constituted a threat to Q. ilex ecosystems and the implications are further discussed.The authors are grateful to A. Solla and his team from the Centro Universitario de Plasencia-Universidad de Extremadura (Spain) for helping in the acorns collection and to the CIEF (Centro para la Investigación y Experimentación Forestal, Generalitat Valenciana, Valencia, Spain) for providing the acorns. This research was supported by funding from the project AGL2011- 30438-C02-01 (Ministerio de Economía y Competitividad, Spain).Mora-Sala, B.; Abad Campos, P.; Berbegal Martinez, M. (2018). Response of Quercus ilex seedlings to Phytophthora spp. root infection in a soil infestation test. European Journal of Plant Pathology. https://doi.org/10.1007/s10658-018-01650-6SÁlvarez, L. A., Pérez-Sierra, A., Armengol, J., & García-Jiménez, J. (2007). 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Overexpression of Myocilin in the Drosophila Eye Activates the Unfolded Protein Response: Implications for Glaucoma

Glaucoma is the world's second leading cause of bilateral blindness with progressive loss of vision due to retinal ganglion cell death. Myocilin has been associated with congenital glaucoma and 2-4% of primary open angle glaucoma (POAG) cases, but the pathogenic mechanisms remain largely unknown. Among several hypotheses, activation of the unfolded protein response (UPR) has emerged as a possible disease mechanism.We used a transgenic Drosophila model to analyze whole-genome transcriptional profiles in flies that express human wild-type or mutant MYOC in their eyes. The transgenic flies display ocular fluid discharge, reflecting ocular hypertension, and a progressive decline in their behavioral responses to light. Transcriptional analysis shows that genes associated with the UPR, ubiquitination, and proteolysis, as well as metabolism of reactive oxygen species and photoreceptor activity undergo altered transcriptional regulation. Following up on the results from these transcriptional analyses, we used immunoblots to demonstrate the formation of MYOC aggregates and showed that the formation of such aggregates leads to induction of the UPR, as evident from activation of the fluorescent UPR marker, xbp1-EGFP. CONCLUSIONS / SIGNIFICANCE: Our results show that aggregation of MYOC in the endoplasmic reticulum activates the UPR, an evolutionarily conserved stress pathway that culminates in apoptosis. We infer from the Drosophila model that MYOC-associated ocular hypertension in the human eye may result from aggregation of MYOC and induction of the UPR in trabecular meshwork cells. This process could occur at a late age with wild-type MYOC, but might be accelerated by MYOC mutants to account for juvenile onset glaucoma