Material Transport Scheduler

What it is for

A shared cart or vehicle may be busy when the next material move is requested. This scheduler assigns a list of requests to identical vehicles and shows when each move can start, when it is delivered and when its vehicle is available again.

Enter each trip as name, request time, loaded travel time and empty return time, all in seconds, and choose the number of vehicles. Requests are processed by request time; ties keep their listed order. Each request is assigned to the vehicle that becomes available earliest.

This is a standalone planning estimate, separate from the Twinworks production model. Network mode adds vehicle locations and shared-segment traffic.

Worked example

Enter the following requests and choose 1 vehicle:

Move A,0,60,30
Move B,10,60,30
Move C,20,45,20

Move A starts at 0 s, is delivered at 60 s and frees the vehicle at 90 s. Move B therefore starts at 90 s, waits 80 s, is delivered at 150 s and frees the vehicle at 180 s. Move C starts at 180 s, waits 160 s, is delivered at 225 s and returns at 245 s.

The tool summarises: 3 moves scheduled; mean wait 80.0 s, maximum wait 160.0 s, fleet utilization 100.0 %. The final return is at 245 s.

Model a route network

To account for shared aisles, enter one two-way segment per line under Optional route network. Each row has two locations, the travel time in seconds and the maximum number of vehicles on the segment at once:

Depot,Aisle,10,1
Aisle,Station,15,2

Enter a depot from the network and change the trip rows to name, request time, pickup location and destination:

Move A,0,Depot,Station
Move B,0,Depot,Station

With two vehicles, the second vehicle waits 10 seconds for the first to clear the capacity-one segment. Both directions share the same segment capacity. The result shows pickup and delivery times, traffic wait, each empty and loaded route, and peak occupancy per segment. After delivery a vehicle stays at its destination; before its next pickup it travels there empty.

A Production baselines table lists each move's loaded cycle and reverse empty return. Copy a representative pair into a Twinworks shared-vehicle transport station (cycle time and empty return). These are uncongested fixed durations; the factory model does not receive network traffic or positions, but its shared resource pool still represents competition for vehicles.

Vehicles take the shortest uncongested route and do not reroute. Requests and segment queues are first-come-first-served, and the first idle vehicle by number is assigned. Intersections, loading, charging and breakdowns are not simulated.

How to read the result

The schedule lists each request, assigned vehicle, start, delivery and availability; network mode adds pickup time, traffic wait and both routes, plus a segment table with peak occupancy and traversals — a segment with many traversals at capacity is your congestion point.

Mean wait measures delay before dispatch. Utilization divides occupied vehicle time by fleet time until the final return or delivery.

Tips and common mistakes

• Use seconds for all request, loaded and return times.
• Include a realistic empty return; the vehicle is occupied until that time finishes.
• Loaded travel must be positive, while request and return times can be zero.
• Compare alternative fleet sizes with the same requests and assumptions.

FAQ

Can vehicles have different speeds?

No. Vehicles are treated as identical; each request supplies its own loaded and empty travel durations.

Does delivery make the vehicle immediately available?

Only if its empty return time is zero. Otherwise the vehicle remains occupied until the return is complete.

Does this model congestion or vehicle position?

Fixed-time mode does not. Network mode tracks locations and queues vehicles when a shared segment is at capacity, including traffic in opposite directions.

Can the scheduler run directly inside a production simulation?

The network planner remains separate. Copy its suggested baseline cycle and return times into a production transport station; the production model will use those fixed values and will not simulate this network’s traffic automatically.