However it does not work.

It would probably help if you could describe what "does not work", and what you do observe.

For example I tried with: rostopic echo /iiwa/command/jointAngles 0,0,0,0,0,0,0.2. It shows rostopic: error: you may only specify one input topic

That doesn't work because you're not using the correct syntax, not because khansari/iiwa is faulty. rostopic echo .. would print incoming messages, it doesn't send something to the node. Please see the rostopic documentation. Look at rostopic pub.

I used as follow: rostopic pub -1 /iiwa/command/cartPosition iiwa/IIWAMsg -- '[600.5455465250951, 1.8979595305782153, 538.6429244423919]' ERROR: Not enough arguments: * Given: [[600.5455465250951, 1.8979595305782153, 538.6429244423919]] * Expected: ['isJointControl', 'cartPosition', 'cartForces',..

Is this is in correct syntax? Thank you

No, it's not. Try rostopic pub -1 /iiwa/command/cartPosition <tab> <tab> (where <tab> is the key on your keyboard). That should give you a message template to fill in.

Alternatively you could of course just write a simple (Python) node that publishes those messages.

I tried but didn't see any message template.

Are you sure that you have sourced the workspace where khansari/iiwa is built in? If not, rostopic will not be able to auto-complete the message structure. Verify you have things setup correctly by doing a rostopic info /iiwa/command/cartPosition. It should show the correct msg type.

rostopic info /iiwa/command/cartPosition shows Unknown topic /iiwa/state/cartPosition. Actually there are only /iiwa/command and /iiwa/state topics if I use rostopic list. However rostopic echo /iiwa/state/cartPosition works. Although rostopic info /iiwa/state/cartPosition also shows same errors.

Ok, so cartPosition is a sub field of command? In that case you should do rostopic pub /iiwa/command <tab> <tab>. It should then auto-complete the msg.

If you haven't already, I'd really recommend doing some of the ROS tutorials that deal with msgs. To get a feel for it/them.