Short lead times, low stock levels and high flexibility - these goals are becoming increasingly important when it comes to internal material flow. Driverless transport systems open up new possibilities for increasing efficiency. Planning and managing driverless systems in combination with manned vehicle systems poses a great challenge for companies, but a hybrid environment can also offer a high degree of flexibility.
These are the questions that logistics managers usually ask themselves: How can the different modes of transport be planned and coordinated in one centralized system to achieve greater flexibility? What is the best way to communicate and prioritize the transports being processed? Which vehicle is assigned which transport order and how can vehicle collisions at bottlenecks be avoided?
Developments and challenges
What remains a future concept in passenger transport is very close to reality in internal logistics. Driverless modes of transport are already being used and planned in a way that enhances fleet utilization to get the most efficient results, taking into account requirements, deadlines, vehicle suitability and many other parameters.
If you take a look at the history of Automated Guided Vehicle Systems (AGVSs), they were initially introduced for technical reasons- mostly for shuttle journeys in concrete, confined areas. As the development of technology progressed, however, the areas of application for AGVSs became increasingly flexible. Technological developments open up new possibilities for internal logistics optimization , but they also bring new challenges. Despite the continuous development of technology, most AGVSs are still being introduced today as pilot projects, without considering a holistic strategy for internal material flows. Most autonomous fleets consist of vehicles from a wide variety of manufacturers and as a rule there is limited communication between vehicles, particularly between manned vehicles and Automated Guided Vehicles (AGVs).
At present, vehicle scheduling is essentially grounded upon a few simple rules and regulations and the defined areas or capacity of an AGVS. Many complications can therefore arise when pooling vehicles and it is difficult to establish a comprehensive control system. Load peaks are poorly compensated for and foresighted collision prevention between different AGVSs is difficult to achieve. If failures occur, it is not usually possible to integrate other vehicles into the system as replacements.
Integrated planning and control for greater efficiency
AGVSs should, however, be controlled uniformly and centrally, in coordination with manned vehicles. For efficient and punctual dispatches, all vehicles in use need to be coordinated in an integrated manner. Which transport order should be assigned to which vehicle? To answer this question, the following factors must be considered:
- Which transport orders are currently pending?
- What is their priority?
- What needs to be transported? From which location to which destination?
- What requirements does the vehicle have to meet?
- When will the material be ready?
Information about the entire vehicle pool is just as important as:
- current statuscurrent position
- technical features
- loading capacity
- area allocation
Real-time communication plays a decisive role in this. Vehicle drivers can receive and transmit all necessary information via mobile devices such as smartphones, tablets or terminals. The various AGVSs are connected via interfaces.
But an integrated transport control system not only plays an important role in transport scheduling for heterogeneous transport fleets. It simultaneously regulates internal transport, which can prevent vehicle collisions in bottlenecks; a situation that can lead to a standstill for AGVSs - especially if the vehicles are not from the same manufacturer.
Another decisive advantage of order and resource pooling is order schedule optimization. Taking into account all transport orders and resources, scheduling decisions can be made automatically in real time, which significantly minimizes empty vehicle runs, for example.
Illustration: Optimized vehicle allocation taking into account the empty journey distance.
Since the vehicle pool for mixed systems is significantly larger and these vehicles can operate in common areas, order peaks can also be compensated for by a uniform control system. On top of this, additional transport systems or manned vehicles can automatically be assigned to provide support in the event of a breakdown.
Transparency is another great advantage. Integrated monitoring and reporting for all of the vehicles in use not only makes it possible to measure the utilization and reliability of autonomous systems, but also to gradually improve logistics processes.
The potential of driverless systems in internal logistics is great. However, these systems are often more difficult to manage centrally and uniformly, especially when combined with manned transport systems and fleets originating from different manufacturers. It is therefore important to create interfaces in order to be able to plan and manage transports as efficiently and comprehensively as possible.
Do you already use AGVSs? How do you plan your internal transports efficiently?
This article was originally posted on the All Things Supply Chain blog.