. The urdf using tree form that does not support parallel robots (close loop robots).
. The sdf using graph form that is more advanced.
. Using Solidworks (edition>2013) and ros tool 'SolidWorks to URDF exporter' plugin can generate urdf.
* solidworks版本要新,example用的2016年的
* 装配时不能有任何close loop joint,有close loop joints要拆散成open loop
* 基本的参数,如link,joint,inertial可以自动生成
. 如果有close loop joints, 可以在转换成sdf后,手动修改xml文件
. URDF to SDF:gz sdf -p ./name.urdf > ./name.sdf
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* solidworks装配件中,所有部件都必须是最低层次的parts,不能是低一层的装配件
* solidworks的close loop robot,首先正常装配,并且调整到合适的位置
* 其次,拆散配合,使close loop robot变成合适的open loop robot
* 使用 'SolidWorks to URDF exporter' 插件,按GUI步骤导出urdf,稍加修改就可以在rviz中检查
* URDF to SDF:gz sdf -p ./name.urdf > ./name.sdf
* 下面就是修改SDF文件,添加joints,恢复成close loop robot.
* Each element on SDF is defined with respect to a specific reference frame:
- Links are defined on the parent model's frame
- Joints are defined on the child link's frame
SDF中的joint pose如果和reference frame重合(offset为0),则
否则,offset joint pose 需要显式的写出。
* offset joint pose可以在solidworks中测量。注意,测量joints点相对于child link's frame. 测量前可以锁定所有活动部件。
* joints 根据需要再设置limits
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