Thanks, so this suggests it is not related to the use of Vuforia. Might be worth  consulting the UNITY website / forum.

Thank you for your valuable suggestion. I tried doing it without using Vuforia and the AR camera. I first tried loading the images from the folder and the image sequences worked fine. But when i tried using the Assetbundle i still got the same result.

OK. In this case, you will want to verify that you can load the Asset Bundle and reproduce the same issue without using Vuforia (i.e. just with a Unity project with a standard Camera and no Vuforia ARCamera or other Vuforia prefabs),

and nail down the actual cause of the issue, as this sounds like possibly related to Unity itself, rather than Vuforia.

Thank your for your response AlessandroB. I built my assetbundles with the Buildtarget set to Android. This is the code I used :

public class AssetBundleExporter 
{
    [MenuItem("Assets/AssetBundle/Android")]
     static void ExportAssetBundle()
    {
        // Bring up save panel
        string path = EditorUtility.SaveFilePanel ("Save Resource", "", Selection.activeObject.name, "");
        if (path.Length != 0) {
            Object[] selection = Selection.GetFiltered (typeof(Object), SelectionMode.DeepAssets);

            BuildPipeline.BuildAssetBundle (
                Selection.activeObject, 
                selection, path + "_android.unity3d", 
                BuildAssetBundleOptions.CollectDependencies | BuildAssetBundleOptions.CompleteAssets,
                BuildTarget.Android);

            Selection.objects = selection;
        }
}
}

Hi, this might be due to the BuildTarget that you did select when creating your AssetBundle:

• AssetBundles can be built for different target platforms (e.g. Windows, Android, iOS, ...); therefore, if you build the AssetBundle by yourself, make sure to select the appropriate BuildTarget option (for example, an Asset Bundle built for Windows might not necessarily work when imported into an Android app); also, AssetBundles built with a previous Unity version may not be compatible with newer Unity versions; for more details, see:
  
  • http://docs.unity3d.com/Documentation/ScriptReference/BuildTarget.html
  • http://docs.unity3d.com/Documentation/ScriptReference/BuildPipeline.BuildAssetBundle.html

See also:

https://developer.vuforia.com/forum/faq/unity-how-can-i-augment-my-image-target-model