use strict;
use warnings;
use XML::Simple;

my $xml = new XML::Simple (
  RootName => 'Task',
  XMLDecl => '<?xml version="1.0" encoding="UTF-8"?>',
);

my @waypoints = (
  { Long => 1, Lat => 2, SeqNo => 1 },
  { Long => 3, Lat => 4, SeqNo => 2 },
);

my $waydata = {
   'xmlns' => "http://Task.CUIntegration.com",
   'xmlns:xsi' => "http://www.w3.org/2001/XMLSchema-instance",
   'xsi:schemaLocation' => "http://Task.CUIntegration.com Task.xsd",
   'ID' => ['ID'],
   'Type' => ['Loop'],
   'Destination' => ['Velocity'],
   'Waypoint' => [ @waypoints ],
};

print $xml->XMLout($waydata);