output orders insert several inputs and send to the controller LARAVEL

I need a little help with this, I'm a little new in laravel and js, what I want to achieve is to insert several inputs (products) to an output order (or detail) and send it to the controller. I have the js to insert several records of inputs (that I found in this same site) that works perfectly for me. What I can not do is decode the JSON (since the code has been sent by JSON) to send it to the controller and process it to save it in the database.

I am using this solution but I can not process them in the controller: Create dynamic input with jQuery

 <script type="text/javascript">
  // Refresca Producto: Refresco la Lista de Productos dentro de la Tabla
  // Si es vacia deshabilito el boton guardar para obligar a seleccionar al menos un producto al usuario
  // Sino habilito el boton Guardar para que pueda Guardar
    function RefrescaProducto(){
        var ip = [];
        var i = 0;
        $('#guardar').attr('disabled','disabled'); //Deshabilito el Boton Guardar
        $('.iProduct').each(function(index, element) {
            i++;
            ip.push({ id_pro : $(this).val() });
        });
        // Si la lista de Productos no es vacia Habilito el Boton Guardar
        if (i > 0) {
            $('#guardar').removeAttr('disabled','disabled');
        }
        var ipt=JSON.stringify(ip); //Convierto la Lista de Productos a un JSON para procesarlo en tu controlador
        $('#ListaPro').val(encodeURIComponent(ipt));
    }
       function agregarProducto() {

            var sel = $('#pro_id').find(':selected').val(); //Capturo el Value del Producto
            var text = $('#pro_id').find(':selected').text();//Capturo el Nombre del Producto- Texto dentro del Select


            var sptext = text.split();

            var newtr = '<tr class="item"  data-id="' +sel+'" >';
            newtr = newtr + '<td class="iProduct" >' + text + '</td>';
            newtr = newtr + '<td><input  class="form-control col-sm-1" id="1" name="cantidad" type="text" value="" required /></td>';
            newtr = newtr + '<td><button type="button" class="btn btn-danger btn-xs remove-item"><i class="fa fa-times"></i></button></td></tr>';

            $('#ProSelected').append(newtr); //Agrego el Producto al tbody de la Tabla con el id=ProSelected

            RefrescaProducto();//Refresco Productos

            $('.remove-item').off().click(function(e) {
                $(this).parent('td').parent('tr').remove(); //En accion elimino el Producto de la Tabla
                if ($('#ProSelected tr.item').length == 0)
                    $('#ProSelected .no-item').slideDown(300); 
                RefrescaProducto();
            });        
           $('.iProduct').off().change(function(e) {
                RefrescaProducto();
           });
    }
</script>

  <div class="container col-sm-offset-3 " >
    <h3>Agregar insumos</h3>
    <!-- Trigger the modal with a button -->
    <button type="button" class="btn btn-info" data-toggle="modal" data-target="#myModal">Agregar</button>
      <input type="hidden" id="ListaPro" name="ListaPro" value="" required />

    <table id="TablaPro" class="table col-sm-9" >
        <thead>
            <tr>
                <th>Insumo</th>
                <th>Cantidad</th>

                <th>Acción</th>
            </tr>
        </thead>
        <tbody id="ProSelected"><!--Ingreso un id al tbody-->
            <tr>

            </tr>
        </tbody>
    </table>

    <!-- Modal -->
    <div class="modal fade" id="myModal" role="dialog">

        <div class="modal-dialog">

            <!-- Modal content-->
            <div class="modal-content">
                <div class="modal-header">
                    <button type="button" class="close" data-dismiss="modal">&times;</button>
                    <h4 class="modal-title">Agregar Insumo a la lista</h4>
                </div>
                <div class="modal-body">
                     <div class="form-group">
                                <label>Insumos</label>
                            <select class="selectpicker form-control" id="pro_id" name="pro_id" data-width='100%' >
                                   @foreach($newinsumos as $newinsumo)
                                    <option value="{{$newinsumo->id}}">{{$newinsumo->nombre}}</option>
                                    @endforeach
                            </select>
            </div>
                </div>
                <div class="modal-footer">
                    <!--Uso la funcion onclick para llamar a la funcion en javascript-->
                    <button type="button" onclick="agregarProducto()" class="btn btn-default" data-dismiss="modal">Agregar</button>
                </div>
            </div>

        </div>
    </div>

driver:

      $data = array();
      foreach($_POST as $key => $value) {  //Recibo el los valores por POST 
        $data[$key] = $value;  
     }

     //dd($data);

      $acturl = urldecode($data['ListaPro']); //decodifico el JSON
      $productos = json_decode($acturl,true);

    foreach ($productos  as $pro) {

         $misProductos = array(
            'cantidad' => $pro->cantidad,
            'insumo_id' => $pro->id_pro,//así llamamos al id del producto en la vista en la funcion RefrescaProducto      
        );
}

print_r ($ products);

Array ( [0] => Array ( [id_pro] => ) )

Error:

ErrorException in OrdenSalidaController.php line 74:
Trying to get property of non-object

dd ($ products);

array:1 [▼
  0 => array:1 [▼
    "id_pro" => ""
  ]
]

dd ($ data);

    array:12 [▼
  "_token" => "htxTHiVFO7totwCWcnYBMjaEArlBsD99prqueEBo"
  "url" => "http://localhost:8888/insumos/desarrollo/public/admin/orden_salidas"
  "id" => "0"
  "page" => "1"
  "fecha_ingreso" => "2018-01-10"
  "responsable" => "Rodrigo Ortiz"
  "establecimiento" => "3"
  "detalle" => "44"
  "_wysihtml5_mode" => "1"
  "ListaPro" => "%5B%7B%22id_pro%22%3A%22%22%7D%2C%7B%22id_pro%22%3A%22%22%7D%5D"
  "cantidad" => "3"
  "pro_id" => "5"
]

pd: if I add more than one input to the output order, it only brings me, as you can see with the dd ($ data) the last input? How can I solve this?

I hope you can help me, try to be as clear as possible. Thank you very much in advance.