Severity: Warning
Message: file_get_contents(https://...@gmail.com&api_key=61f08fa0b96a73de8c900d749fcb997acc09&a=1): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
Filename: helpers/my_audit_helper.php
Line Number: 197
Backtrace:
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 197
Function: file_get_contents
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 271
Function: simplexml_load_file_from_url
File: /var/www/html/application/helpers/my_audit_helper.php
Line: 3165
Function: getPubMedXML
File: /var/www/html/application/controllers/Detail.php
Line: 597
Function: pubMedSearch_Global
File: /var/www/html/application/controllers/Detail.php
Line: 511
Function: pubMedGetRelatedKeyword
File: /var/www/html/index.php
Line: 317
Function: require_once
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The operating process of rotary crane is often very complicated and there are many unpredictable conditions, such as the condition of the load sway around the hook, which will undoubtedly make the sway characteristics analysis of the system and the controller design become more difficult. In addition, for the purpose of decreasing the complexity of controller design, traditional control methods often perform model linearization processing operation, which can reduce the robustness of the system to a certain extent (when the parameters of the crane are unknown or there are external disturbances, the control capability of traditional control methods will be largely degraded). Based on the above, this paper first uses kinematic analysis to derive rotary crane model, and then proposes a nonlinear controller based on adaptive back-stepping method to achieve pendulum elimination and boom positioning. Then the stability of the system is proved by Lyapunov Lemmas. Finally, the performance of the system is verified by comparing the experimental results of different methods.
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http://dx.doi.org/10.1016/j.isatra.2022.11.011 | DOI Listing |