Bind <div> to element of Angular controller - angularjs

Question

We have a somewhat complicated model on an AngularJS controller:
function controller($scope) {
$scope.model = {
childmodel1: {
childmodel2: {
property1: 'abc',
property2: 3,
property3: 0.5,
property4: 'abc'
}
}
}
}
In the HTML markup, we don't want to repeat the whole access chain everytime we access childmodel2:
<div ng-controller="ctrl">
<div>
<input type="text" ng-model="model.childmodel1.childmodel2.property1" />
<input type="text" ng-model="model.childmodel1.childmodel2.property2" />
<input type="text" ng-model="model.childmodel1.childmodel2.property3" />
<input type="text" ng-model="model.childmodel1.childmodel2.property4" />
</div>
</div>
Is there an AngularJS directive that creates a sub-scope like this:
<div ng-controller="ctrl">
<div ng-unknowndirective="model.childmodel1.childmodel2">
<input type="text" ng-model="property1" />
<input type="text" ng-model="property2" />
<input type="text" ng-model="property3" />
<input type="text" ng-model="property4" />
</div>
</div>
It's the same thing that's done on ng-repeat, but without the repetition :)
We tried ng-scope, ng-controller, ng-model, none of them works this way. Googling didn't yield any results, we don't know the terminology to search for.

Answer 1

Thank you #Ufuk, here's my solution:
mt.directive('subscope', function () {
return {
scope: {
subscope: '='
}
};
});
and
<div ng-controller="ctrl">
<div subscope="model.childmodel1.childmodel2">
<input type="text" ng-model="subscope.property1" />
<input type="text" ng-model="subscope.property2" />
<input type="text" ng-model="subscope.property3" />
<input type="text" ng-model="subscope.property4" />
</div>
</div>

Answer 2

You can use ng-init to suppress the access chain
<div ng-init="childmodel2 = model.childmodel1.childmodel2">
<input type="text" ng-model="childmodel2.property1" />
<input type="text" ng-model="childmodel2.property2" />
<input type="text" ng-model="childmodel2.property3" />
<input type="text" ng-model="childmodel2.property4" />
</div>
It creates alias model. More appropriate you create the alias in your controller like
$scope.childmodel2 = $scope.model.childmodel1.childmodel2 // and remove ng-init from HTML
Demo