rossvcclient handshake fail in Matlab2018​a\ros-Kine​tic​\Gazeb​o-7 and Gazebo-8

I get handshake errors trying to follow the Robotic System Toolbox Example (Add, Build, and Remove Objects in Gazebo). I tried unsuccessfully on two different computers, both with ROS Kinetic and two different versions of Gazebo (7 and 8), I can't control the models (i.e. applyForce) despite I could see those (getSpawnedModels).

After a connection to Gazebo_ros platform with:

rosinit('ipaddress')
gazebo = ExampleHelperGazeboCommunicator();

I Spawn a Simple Sphere despite the handshake error message (I can see the sphere in Gazebo):

ball = ExampleHelperGazeboModel('Ball')
ball = 
ExampleHelperGazeboModel with properties:
      Name: 'Ball'
  ModelObj: [1×1 org.apache.xerces.dom.DocumentImpl]
     Links: []
    Joints: []

>>

spherelink = addLink(ball,'sphere',0.3,'color',[0 0 1 1])
spherelink =
  'link0'

>>

spawnModel(gazebo,ball,[1,0.3,0.3]);
Error using ExampleHelperGazeboCommunicator/startModelServices (line 334)
Failed to create a /gazebo/get_model_state service client.
Error in ExampleHelperGazeboCommunicator/spawnModel (line 290)
              startModelServices(obj);
[ERROR] ServiceClientHandshakeHandler - Service client handshake failed: client wants service /gazebo/get_model_state to have md5sum af0f702011820738976b120226dc9d96, but it has 4c515e936d3319c9610c559c60bfc3d4. Dropping connection.

>>

models = getSpawnedModels(gazebo)
models =
2×1 cell array
  {'ground_plane'}
  {'Ball'        }

>>

duration = 1; % Seconds
>> 

forcevec = [-25 0 0]; % Newtons
>> 

applyForce(spawnedBall, spherelink, duration, forcevec);
Undefined function or variable 'spawnedBall'.

Answer 1

[YJ Lim]

Hi, If you still have the same issues, I wonder if I can have your .m file since I can't mimic your problem at my end. Thanks.