TANDEM_CRANE_SYNC
Tandem-lift follower control: matches the master crane's velocity and holds a fixed spacing, stopping both on excess sync error.
When to use it
Use TANDEM_CRANE_SYNC when two cranes carry one long load between them and the follower must track the master's travel at a fixed spacing, so the load stays level and the two cranes do not pull against each other.
Interface
The published port signature. This is the whole of what the block exposes to your program — the implementation body is not shown here and ships with the download.
Inputs
| Port | Type | Unit |
|---|---|---|
| ENABLE | BOOL | — |
| MASTER_POS | REAL | m |
| MASTER_OK | BOOL | — |
| FOLLOW_POS | REAL | m |
| FOLLOW_OK | BOOL | — |
| GAP_SP | REAL | m |
| KP | REAL | (m/s)/m |
| TI | REAL | s |
| TRIM_LIM | REAL | m/s |
| V_MAX | REAL | m/s |
| A_MAX | REAL | m/s2 |
| SYNC_TOL | REAL | m |
| ERR_LIM | REAL | m |
| FILT_T | TIME | — |
| ACK | BOOL | — |
Outputs
| Port | Type | Unit |
|---|---|---|
| FOLLOW_SPD | REAL | m/s |
| SYNC_ERR | REAL | m |
| SYNCED | BOOL | — |
| MASTER_SPD | REAL | m/s |
| STOP_BOTH | BOOL | — |
| VALID | BOOL | — |
| ALM_SYNC_FAULT | BOOL | — |
| ALM_POS_FAULT | BOOL | — |
| ALM_CFG_ERR | BOOL | — |
IEC 61499 event interface
EI INIT, REQ·EO INITO, CNF
Supervised control write
TANDEM_CRANE_SYNC commands a real actuator. It is written to sit underneath your own interlock, permissive and protection logic — not to replace it. Commission it as you would any control block you wrote yourself.
Validation evidence
- Tests
- 11
- Simulated scans
- 172
- Simulator
- v0.1.0
Complete IEC 61131-3 implementation with a published test suite that runs on the vplant simulator. The counts above are that suite, executed on this build.
- Conforms to IEC 61131-3
- Conforms to IEC 61499
Download TANDEM_CRANE_SYNC — free
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