How can we implement join queries in phalcon ORM without using direct PHQL queries.
You can use the QueryBuilder:
$robots = $this->modelsManager->createBuilder() ->from('Robots') ->join('RobotsParts') ->order('Robots.name') ->getQuery() ->execute();
https://docs.phalcon.io/en/1.1.0/reference/phql.html#creating-queries-using-the-query-builder