packaging filler interlock (graphical LD)¶


suite id	`g_packaging_filler`
domain	packaging
language	LD-graphical
difficulty	medium
validation status	validated
origin	authored
license	CC-BY-4.0

Authored for this suite to cover this domain with genuine control logic

What is proved¶

From benchmarks/packaging/g_packaging_filler/props.yaml. What each kind claims, and what it becomes on either route, is on The properties we prove.

id	kind	claim	requirement
`P1`	`invariant`	`!(fill_valve && full)`	The fill valve must never open on an already-full bottle (overflow protection).

Variants¶

file	expected verdict	violates	method
`clean.xml`	SAFE	none	expert
`bomb.xml`	VIOLATION	`P1`	fault-injection

Files¶

file	what it is	size	sha256
`benchmark.yml`	benchmark metadata	1.0 KB	`4949e6fef4a5`
`bomb.xml`	ladder program, PLCopen XML	3.4 KB	`1d48a0a44a9b`
`clean.xml`	ladder program, PLCopen XML	2.9 KB	`bef8ce7ea9e9`
`props.yaml`	property file	0.2 KB	`01cd5a39fbe1`

Structured text, derived¶

Read off the ladder graph by runner/ld_to_st.py: every rung's contacts and coils rewritten as IEC 61131-3 assignments, in the same series/parallel logic the PLCopen XML encodes. This is a reading aid, not a second source of expected verdicts; ESBMC verifies the ladder program shown above, never this rendering.

bomb.xmlclean.xml

PROGRAM g_packaging_filler_bomb
VAR_INPUT
    bottle_present : BOOL;
    full : BOOL;
    start : BOOL;
    maint : BOOL;
END_VAR

VAR_OUTPUT
    fill_valve : BOOL;
    reject : BOOL;
END_VAR


fill_valve := (((NOT full OR (full AND maint)) AND bottle_present) AND start);
reject := (NOT bottle_present AND start);

END_PROGRAM

PROGRAM g_packaging_filler_clean
VAR_INPUT
    bottle_present : BOOL;
    full : BOOL;
    start : BOOL;
    maint : BOOL;
END_VAR

VAR_OUTPUT
    fill_valve : BOOL;
    reject : BOOL;
END_VAR


fill_valve := ((NOT full AND bottle_present) AND start);
reject := (NOT bottle_present AND start);

END_PROGRAM

Recorded runs¶

A task can carry two routes. ld is ESBMC's ladder front end reading the program directly. via C is the same solver reached through Beremiz and MatIEC, which is the only route that reaches ST, IL, FBD and SFC; see How ESBMC-PLC works.

g_packaging_filler__bomb (props.yaml, expected VIOLATION): v8.4 VIOLATION
g_packaging_filler__bomb__viac via C (props.yaml, expected VIOLATION): master VIOLATION
g_packaging_filler__clean (props.yaml, expected SAFE): v8.4 SAFE
g_packaging_filler__clean__viac via C (props.yaml, expected SAFE): master SAFE