With　the　arrival　of　Industry　4.0　and　the　strategic　plan　of　Made　in　China　2025,　and　along　with　the　continuous　reduction　of　the　domestic　population　in　recent　years　and　the　rising　cost　of　manpower　brought　about　by　it,　the　robotic　arm　as　an　important　tool　for　the　liberation　of　labor,　its　development　and　Application　becomes　more　and　more　important.　In　this　context,　in　order　to　meet　the　requirements　of　safer,　smoother,　faster　and　more　efficient　control,　a　Region　Informed　RRT*　Connect　algorithm　based　on　the　optimized　sampling　space　of　the　inclined　cylinder　has　been　proposed　for　the　path　planning　and　trajectory　optimization　of　a　five-degree-freedom　manipulator.　An　improved　seventh-polynomial　optimized　trajectory　planning　method　has　been　adopted　to　effectively　prevent　the　sudden　change　of　the　manipulator＇s　joint　angles.　The　algorithm　has　been　fully　validated　on　MATLAB　software　environment　and　existing　self-developed　manipulator.　The　experimental　analysis　results　have　shown　that　the　Region　Informed　RRT*　Connect　algorithm　has　got　obvious　performance　improvement　comparing　with　traditional　RRT　and　other　algorithms　in　terms　of　average　path　search　time,　number　of　extended　nodes,　path　length,　etc.　The　motion　path　obtained　by　the　improved　polynomial　trajectory　optimization　algorithm　has　been　smoother,　better　in　energy　and　with　minimum　impact,　which　can　be　well　applied　to　manipulator　motion　planning.　©　2023　IEEE.