DBR Scheduler
Overview
The DBR (Drum-Buffer-Rope) Scheduler skill provides comprehensive capabilities for implementing constraint-based production scheduling. It supports drum schedule generation, buffer management, and rope release scheduling to maximize throughput while minimizing WIP.
Capabilities
- Drum schedule generation
- Time buffer calculation
- Shipping buffer management
- Constraint buffer monitoring
- Rope release scheduling
- Buffer penetration tracking
- Schedule synchronization
Used By Processes
- TOC-002: Drum-Buffer-Rope Scheduling
- CAP-002: Production Scheduling Optimization
- TOC-001: Constraint Identification and Exploitation
Tools and Libraries
- Production scheduling systems
- ERP integration APIs
- Buffer management tools
- Real-time monitoring platforms
Usage
skill: dbr-scheduler
inputs:
constraint_resource: "CNC Machine 3"
constraint_capacity: 8 # hours per day
orders:
- order_id: "ORD001"
quantity: 100
due_date: "2026-02-15"
constraint_time: 2.5 # hours
- order_id: "ORD002"
quantity: 50
due_date: "2026-02-10"
constraint_time: 1.5
buffer_times:
constraint_buffer: 2 # days
shipping_buffer: 1 # day
assembly_buffer: 0.5 # days
outputs:
- drum_schedule
- rope_release_schedule
- buffer_status
- order_priorities
- shipping_dates
DBR Components
Drum
- The schedule for the constraint resource
- Sets the pace for entire system
- Based on customer due dates and constraint capacity
Buffer
- Time protection before constraint (constraint buffer)
- Time protection before shipping (shipping buffer)
- Measured in time, not inventory
Rope
- Release signal for raw materials
- Timed to constraint buffer length
- Prevents excess WIP release
Buffer Management
| Buffer Penetration | Zone | Action | |-------------------|------|--------| | 0-33% | Green | Normal operation | | 34-66% | Yellow | Monitor closely | | 67-100% | Red | Expedite immediately |
Buffer Sizing Guidelines
Constraint Buffer = Production Lead Time x Safety Factor
Where:
- Production Lead Time = Time from release to constraint
- Safety Factor = 1.0-2.0 based on variability
Schedule Synchronization
- Schedule constraint (drum)
- Calculate release dates (rope)
- Set buffer monitoring points
- Communicate shipping commitments
- Monitor buffer penetration
Integration Points
- ERP/MRP systems
- Manufacturing Execution Systems
- Order management systems
- Real-time shop floor data