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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Multi-arm rock drilling robots frequently encounter challenges in extreme environments, such as tunnels, where they are subjected to high-frequency impact loads, multi-degree-of-freedom motion coupling, and large-range motion control vibrations. First, we propose a collision-free path planning method that combines an improved genetic algorithm (IGA) and an improved artificial potential field method. This method is based on the kinematic model of the rock drilling robot. This method plans a collision-free path for the coordinated drilling operation of multiple drilling arms by optimizing the shortest moving distance of the drilling arm ends. Active disturbance rejection motion control is designed to enable precise and stable control of multi-DOF, heavy-duty robotic arms. A mechanical-electrical-hydraulic joint simulation model of the multi-arm cooperative motion control system of the rock drilling robot has been developed. The simulation and experimental results demonstrate that the angle and displacement errors of each joint are constrained to within 1.5 %, with maximum positioning errors of 9.56 mm and 7.32 mm at the extremity of the drilling arm. These results verify the feasibility and effectiveness of the proposed method and system and improve the construction efficiency and automation level of multi-arm rock drilling robots for tunnel rock drilling.
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http://dx.doi.org/10.1016/j.isatra.2025.09.001 | DOI Listing |