So you are asking how to populate array of properties given a list of VC:VirtualMachine objects?
Should be something like
parameters = new Array(); // array of properties
for (var i = 0; i < numberOfVMs; i++) {
var wfInputProp = new Properties();
wfInputProp.put("nameOfInputParam", objVM[i]);
// ... put other inputs if needed by your custom wf
parameters.push(wfInputProp);
}
-Ilian