## 5 New Opportunities for Design and Development of Innovative Last Mile Logistics
### LML for Decentralized Manufacturing Services  
The growth of 3D printing technologies and services has accelerated a new paradigm of manufacturing. 3D printing provides a new opportunity that can decentralize manufacturing by producing parts near consumption, which can lead to shortened supply chains and reduced inventory [112]. Under decentralized manufacturing, LML would be more important as a large set of low-volume and lightweight final products made by decentralized manufacturing may need to be effectively delivered to highly distributed consumer locations through local transports [113]. The 3D printing industry can provide new opportunities in logistics operations, and more insights into the effects of 3D printing on LML should be scrutinized to prepare for the transition to this new paradigm of LML. In this regard, the following topics should be further discussed:  
* LML for local fabshop-based 3D printing: Local 3D printing fabshops can provide a new business opportunity for logistics companies if they are able to offer 3D printing services as well as delivery services at the same time through their local 3D printing shops [114]. This type of local 3D printing is effective for orders that are required to fabricate customized design shapes and high-quality products [113]. As customers simply need to order what they want to manufacture through an online system, the role of LML for the deliveries of 3D printed products to individual customers will become more important. A dynamic local logistics network that is assisted by new mobility options (e.g., drones or UAVs) will be helpful to achieve operational efficiency if a few local fabshops should handle individual low-volume orders requested from highly distributed end-customers.  
LML for consumer-based (home) 3D printing: Consumer-based (home) 3D printing is more suitable for low-end and common products [113]. The acceleration of 3D printing at home would make material flows from material suppliers to end-users more critical [82; 112], and conventional last mile delivery for final products may need a significant transition to last-mile delivery for raw materials. Therefore, rapid replenishment of a wide variety of low-volume materials for customers would be an important decision-making problem in LML. In addition, reverse logistics to reproduce raw materials from disused 3D printed products will emerge as a new competitive edge in LML.
* Concurrent manufacturing logistics (mobile manufacturing): Amazon Technologies, Inc. recently filed patents for mobile manufacturing that enables carriers equipped with 3D printers to take and produce orders at the same time during delivery [115; 116]. This new form of logistics will eliminate the current strict separation between manufacturing and logistics and will provide a great deal of flexibility and competitiveness for offering final products to customers [117]. Mobile manufacturing is expected to open a new way to optimize order lead-time by valuably using delivery time, which has traditionally been considered as cost addition for final delivery. This new approach will be applicable not only to mobile manufacturing of low-variety products within small-sized vehicles (e.g., cars and small trucks) but also to mobile manufacturing of high-variety products within large-sized vehicles (e.g., large trucks and aircraft). For both cases, product quality and autonomous manufacturing in a moving vehicle should be technically and operationally supported for successful LML operations of mobile manufacturing.