Gazebo机器人仿真学习探索笔记(四)模型编辑

Gazebo 機器人仿真學習探索筆記 四 機器人仿真學習探索筆記 四 模型編輯模型編輯 模型編輯主要是自定義編輯物體模型構建環境 也可以將多種模型組合爲新模型等 支持 外部模型導入 需要注意的導入模型格式有相應要求 否在無法導入成功 COLLADA dae STereoLithography stl Scalable Vector Graphics svg 模型導入界面如下 以 Scalable Vector Graphics svg 爲例 直接使用下面命令安裝使用 html view plain copy print 在 CODE 上查看代码片派生到我的代码片 sudo apt get install inkscape 也可以編輯組合模型 這部分內容都是可視化操作 簡潔易學 可直接參考附錄中的官方文檔 編輯好的模型可以重命名 然後另存 twotable 會自動生成如下文件 自動生成的代碼如下所示 model config html view plain copy print 在 CODE 上查看代码片派生到我的代码片 twotable 1 0 model sdf model sdf html view plain copy print 在 CODE 上查看代码片派生到我的代码片 0 0 0 1 0 0 0 1 5 0 8 0 03 0 6 0 6 0 0 1 0 0 0 1 4 0 8 0 04 file media materials scripts gazebo material Gazebo Wood 0 68 0 38 0 5 0 0 0 0 02 1 0 68 0 38 0 5 0 0 0 0 02 1 file media materials scripts gazebo material Gazebo Grey 0 68 0 38 0 5 0 0 0 0 02 1 0 68 0 38 0 5 0 0 0 0 02 1 file media materials scripts gazebo material Gazebo Grey 0 68 0 38 0 5 0 0 0 0 02 1 0 68 0 38 0 5 0 0 0 0 02 1 file media materials scripts gazebo material Gazebo Grey 0 68 0 38 0 5 0 0 0 0 02 1 0 68 0 38 0 5 0 0 0 0 02 1 file media materials scripts gazebo material Gazebo Grey 0 1 23981 0 324 0 0 0 1 0 1 23981 0 324 0 0 0 model table marble meshes table lightmap dae 0 25 0 25 0 25 model table marble meshes table lightmap dae 0 25 0 25 0 25 model table marble materials scripts model table marble materials textures Table Marble Lightmap 0 0 1 可知 sdf 爲 1 6 版本了 附錄 官方文檔 Model Editor Overview This tutorial describes the process of creating a model using the Model Editor Open the Model Editor Make sure Gazebo is installed Start up gazebo gazebo On the Edit menu Go to Model Editor or hit Ctrl M to open the editor Graphical user interface The editor is composed of the following 2 areas The Palette on the left has two tabs The Insert tab lets you insertparts links and other models into the scene to build the model The Modeltab displays a list of all the parts that make up the model you are building The 3D View on the right where you can see a preview of your model andinteract with it to edit its properties and create joints between links The GUI tools on the top toolbar can be used to manipulate joints and links inthe 3D View Add Links Add simple shapes The model editor has three simple primitive geometries that the user can insertinto the 3D view to make a link of the model On the Palette click on the box sphere or cylinder icon underSimple Shapes Move your mouse cursor over the 3D view to see the visual appear andclick release anywhere to add it to the model Tip You can press Esc to cancel adding the currentlink attached to the mouse cursor Add meshes To add a custom mesh Click on the Add button under Custom Shapes which pops up a dialogthat lets you find the mesh you want to add Click on Browse button and use the file browser to find the mesh fileon your local machine If you know the path of the mesh file you can enter itdirectly in the text field box next to the Browse button Note Gazebocurrently only supports importing COLLADA dae STereoLithography stl and Scalable Vector Graphics svg files Click Import to load the mesh file Then add it to the 3D view Create Joints The model editor supports creating several types of joints between links in themodel being edited To create a joint Click on the joint icon on the tool bar This brings up the Joint CreationDialog which allows you to specify different properties of the joint youwant to create As you can see in the dialog the default joint type isa Revolute joint Begin by moving your mouse over the link you wish to create a joint for tosee it being highlighted and click on it This link will be the parent link ofthe joint Next move your mouse to the link which you would like to be the child linkof the joint Click on it to see a colored line connecting the two links anda joint visual attached to the child link The line representing the joint is color coded Play around with differentjoint types to see the colors The joint visual consists of RGB axes which help to give an idea of thecoordinate frame of the joint The yellow arrow indicates the primary axis ofthe joint For example in the case of a revolute joint this is the axis ofrotation Once you have specified all the desired properties of the joint in theJoint Creation Dialog click on the Create button at the bottom to finalizejoint creation Tip You can press Esc any time to cancel the joint creation process Edit your model Note Be careful when editing your model the editor currently has no option to undo your actions Tip All measurements are in meters Edit links The model editor supports editing properties of a link which you wouldalso find in its SDF Note Gazebo 6 supports editinglinks visuals and collisions The ability to edit sensors andplugins are to be implemented in later versions To edit a link s properties Double click on the link or right click and selectOpen Link Inspector A dialog window will appear which containsLink Visual and Collision property tabs As an example try changing the link pose and visual colors Once you are done click onOK to close the inspector Edit joints As mentioned earlier joint properties can also be edited These are propertiesthat you would find in the joint SDF To edit a joint Double click on the line connecting the links or right clickon it and select Open Joint Inspector The joint inspector will appear As an example try changing the joint pose and joint type Once you are done click onOK to close the inspector Saving your model Saving will create a directory SDF and config files for your model As an exercise let s build a simple car and save it The car will have abox chassis and four cylinder wheels Each wheel will be connected to thechassis with a revolute joint Once you re happy with the model you created go to the Model tab in the leftpanel and give it a name Exit When you re done creating the model and you ve saved it go to File and thenExit Model Editor Your model will show up in the main window Edit existing models Rather than creating a model from the ground up you can also edit existing models that are already in the simulation To edit an existing model Make sure you have saved the model you created and you have exited the model editor Alternatively start from a fresh Gazebo instance Insert a model from the Insert tab on the left For example let sinsert a Simple Arm Right click on the model you just inserted and select Edit Model Now you are in the model editor and you are free to add new links to themodel or edit existing ones Extrude SVG files Overview This tutorial describes the process of extruding SVG files which are 2Dimages to create 3D meshes for your models in Gazebo It is sometimeseasier to design part of a model in a program like Inkscape or Illustrator Before starting make sure you re familiar with theModel Editor This tutorial will show you how to make a custom wheel as an svg in Inkscape and import it into Gazebo so that it can be attached to a robot Using the Inkscape SVG editor Document preparation Start Inkscape This will create a blank document First lets change thedocument size to better accommodate our wheel under the File Documentproperties menu select the Page tab and change the document size to acustom size of 100 0 x 100 0 mm Then in the same dialog select the Gridstab press the New button to create a custom grid Then check the Enabled Visible and Snap to visible grid lines only options ChangeSpacing X and Spacing Y to be 10 Draw You can use the different tools pen text stars and shapes etc to createyour geometry In this example the wheel is made from circles pressing theShift Key you can start your circle from the center and using the CTRL keyallows you to keep the roundness of the shape It is possible to combineshapes together making sure that paths are closed and that the part hasa proper thickness Note a stick figure or two circles that touch each other would notresult in valid Gazebo models The SVG paths must create an closed contour withholes where the holes cannot touch the contour or other holes Holes insideholes are treated as solid parts and they can have holes too Gazebo only imports paths but it s easy with Inkscape to transform any shapeto a path Select Select All from the Edit menu Then select thePath Object to Path menu item This will transform every object intoseparate paths and sub paths This transformation is irreversible so if youtransform text into paths you will not be able to alter the text Gazebo does not support grouping Use the Ungroup from the Object menu toseparate groups of paths Save your drawing Save your drawing to an SVG file you can use later in Gazebo Use the Saveoption from the File menu Create a Gazebo Model SDFormat does not support SVG directly it supports 2Dpoly lines The Gazebo Model Editor has an import mechanism that extracts thepoly lines from SVG files and saves them as an SDF model file Launch Gazebo and Select Model Editor from the Edit menu to enter theGazebo Model Editor mode as opposed to the simulation mode Then press the Add button in the Custom Shapes section of the Insert tab Thickness How thick the link will be This corresponds to the extrusionheight in the z axis For the SVG path shown on the right the axis ofextrusion is outwards from the screen Resolution How many pixels in your SVG correspond to a meter Thedefault value 3543 3 px m corresponds to 90 dpi dots per inch which isthe default resolution for several editors