Every component in the Sandbox is described here. The simulation deliberately uses simple, repeatable rules rather than engineering calculations.
P = pressure supply. A/B = working actuator ports. R/R1/R2 = exhaust. X = pilot/control. IN/IN1/IN2 = input. OUT = output. RST = reset.
The four-channel Fuse Box protects Board Sections 1–4. Feeding one Heavy Power Knife Switch from more than one numbered Power Rail feed is a wiring fault: all involved channels latch BLOWN. In RUN, click a blown channel to reset it. If the fault is still present, it immediately trips again. Opening or closing a correctly wired Knife Switch is normal operation and never blows a fuse.
Sections 1–6 calculate their heavy-power state from the matching numbered Power Rail feed, a CLOSED Knife Switch and a HEALTHY matching fuse channel. Electrical/control components physically located in an OFF section can no longer source a live electrical signal, and a board-mounted Indicator Lamp in an OFF section stays dark even if a live wire arrives from another section. Board electrical signals and powered loads obey the current Board Section power state.
The 6-Port Power Rail is the foundation of the Sandbox heavy-power system. Its six numbered sockets are permanently reserved for Board Sections 1–6. Heavy power is deliberately separate from yellow control wiring. The rail works with Knife Switches and the Fuse Box to distribute protected heavy power to Board Sections 1–6.
The 6-Channel Fuse Box provides one protected heavy-power channel for each Board Section 1–6. Each channel has persistent HEALTHY/BLOWN state and participates in automatic fault trips, reset behavior and Board Section power enforcement.
The Air Supply is the starting point for compressed air. Its OUT port supplies air while the main AIR control is ON and the emergency stop is not active. Connect OUT to a valve P port or another pneumatic component that needs pressure. A pneumatic circuit without a live air supply cannot move an actuator.
The Piston turns air pressure into straight mechanical movement. It can push boxes and its visible tip can actuate a mechanical switch when the tip reaches the switch square.
Single Acting — Spring Return: pressure at A extends the piston; removing pressure lets the spring retract it. Double Acting: pressure at A extends it and pressure at B retracts it. Stroke 1–4 determines extension distance. Flow F1–F5 controls movement speed and the maximum stack size the piston can push; larger or blocked stacks can jam.
The Electric Piston is a wire-controlled linear actuator with one yellow IN terminal. PULSE mode extends to the selected stroke and retracts automatically as soon as full extension is reached. LATCH mode alternates on each new OFF→ON pulse: first pulse extends and holds, second pulse retracts. It needs no air supply or valves. Its yellow OUT reports when full extension has been reached: in LATCH mode it stays ON while held extended; in PULSE mode it gives a brief signal as the piston begins its automatic return.
The 3/2 Valve has three working ports and two positions. P receives pressure, A feeds an actuator and R exhausts air. X is the pilot/control port. Pressure at X actuates the valve. It is particularly useful for controlling a single-acting piston.
The 5/2 Valve controls both sides of a double-acting piston. P is pressure, A/B go to the piston and R1/R2 are exhausts. X is the pilot/control port. In this Sandbox, X released makes P feed B and retract the piston; X actuated makes P feed A and extend it. The opposite side is treated as exhausting.
The Manifold splits one air supply into three possible branches. P is the inlet; A, B and C are outlets. In BUILD mode each branch has a green ✓ or red ×. Green is OPEN and red is BLOCKED. Each branch also has its own yellow electrical toggle input below the manifold. A new OFF → ON signal flips only that branch between OPEN and BLOCKED; the signal must return OFF before another toggle can occur. Manual branch buttons remain available. Use it when one supply must feed several pneumatic paths.
The Flow Restrictor reduces flow between IN and OUT. Settings 1–5 are simple Sandbox restriction levels, not engineering flow measurements. Use it to slow pneumatic movement or create timing differences.
The Exhaust gives released air a visible destination. Connect an exhaust path to its E port when you want the circuit drawing to show clearly where discharged air goes.
The Switch can be operated manually, mechanically by a piston, or electrically. Its electrical IN can receive a signal from a sensor or Comparator Box. When active, the switch behaves as if pressed. Its pneumatic OUT can pilot a valve X port, making the switch the bridge between electrical control and pneumatic action. Manual clicking remains available as an override.
A Sensor creates an electrical ON/OFF signal from what it detects. It can be configured for ANY, EMPTY (0%), FILLED (100%), NOT FULL (<100%), FLAGGED, and supported empty-slot detection. Its output can feed lamps, Comparator Boxes, switch electrical inputs, or supported reset inputs.
Example: an EMPTY sensor can detect an empty box condition and trigger a reset or the next step of an automatic cycle.
The Comparator Box has electrical IN1, IN2 and OUT. In BUILD mode click ✎ and choose its type. Existing wiring stays connected when the type is changed.
OR: OUT is ON if either input is ON, including both. AND: OUT is ON only if both inputs are ON. XOR: OUT is ON only if exactly one input is ON; both OFF or both ON gives OFF.
Use AND for two conditions that must both be satisfied, OR when either of two controls may operate something, and XOR when the two inputs must disagree.
The NOT / Inverter is a pure logic part with one yellow IN and one yellow OUT. IN OFF gives OUT ON; IN ON gives OUT OFF. It has no memory, delay, sensor or physical action.
The A/B Signal Selector is a pure electrical logic router. Its IN signal is sent to either A or B. Each new OFF→ON pulse at TOGGLE changes the selected route A↔B and the selector remembers that choice. It has no physical or pneumatic action.
Indicator Lamps make electrical states visible. Assign a signal source, short label text and display color. The lamp follows its source. Lamps are useful both as machine indicators and as troubleshooting aids for watching sensors, switches and Comparator outputs.
The Nozzle represents processing a box. FILL mode keeps the timed fill/counter behaviour and has a configurable 1–100% test fill target so partial fills can be created intentionally. Besides FILL, the nozzle can apply or clear a generic FLAG and can now CORK or UNCORK a box. FLAG/CLEAR FLAG and CORK/UNCORK process the adjacent box for one heartbeat. Cork state is independent of fill level. A corked box cannot be filled; it must be uncorked before any FILL operation can add contents.
A Box is the movable workpiece. Conveyors transport boxes and pistons can push them. Boxes carry a 0–100% fill level: the contents color rises visually from the bottom, so partial fills are visible. 0% is EMPTY, 100% is FILLED, and 1–99% is PARTIAL. A FILL nozzle normally reaches its configured fill target (1–100%); optional 0.5% or 1% random error can leave it below that target. Any value below 100% remains underfilled and can be topped up later. Boxes also carry one generic NORMAL / FLAGGED marker and an independent UNCORKED / CORKED state. New boxes begin UNCORKED.
The Box Dropper creates one new box when clicked manually in RUN or whenever its yellow IN receives a new OFF→ON electrical signal.
In Edit, Default box flag chooses NORMAL or FLAGGED. If nothing is connected to the yellow FLAG terminal, every new box uses that default.
For mixed production, connect a signal to FLAG. At the instant a box is dropped: FLAG OFF = NORMAL and FLAG ON = FLAGGED. The FLAG signal does not drop a box by itself; IN is still the drop command. A locking switch is useful for testing this: wire the locking switch to FLAG and another switch to IN.
The Pusher / Feeder is configured in Edit. In Pusher mode, one trigger moves the box or contiguous queue in front of it one square in the arrow direction, subject to the normal blocking rules. A Recycling Chute is an accepting destination.
In Feeder mode, boxes queue behind the unit. One trigger releases the front box to the output square and advances the remaining contiguous queue one position toward the feeder.
The yellow IN terminal performs one cycle on each new OFF→ON electrical signal. The component can also be clicked manually in RUN for testing.
A Conveyor carries boxes already placed on it. Place START and END on the same row or column. In RUN, open OP, select the conveyor ID, then use STOP, RUN, DIR or JOG. DIR and JOG only work while stopped; JOG is operator-only.
In BUILD, click a conveyor to open its tucked-away editor. The selected conveyor highlights pink. + START and + END extend the belt one square at that end. MOVE asks you to click a new START square and moves the complete conveyor without changing its length. DELETE removes the conveyor but leaves any boxes in place. Conveyors also have − START and − END to shorten them. RUN-mode operation is handled from the collapsible OP panel.
A Conveyor Status Sensor can also report BLOCKED while a running conveyor has a box physically unable to advance. Its exit counter records OUT, FULL and EMPTY. The yellow RST electrical input clears those counts without stopping the conveyor or feed. A box reaching an extended piston may be blocked or deflected.
Place the Spacer Block directly on a conveyor square. Wire an electrical source to IN. Each new OFF→ON pulse toggles the spacer between OFF and ON. When OFF, the spacer is transparent. When ON, randomly spaced boxes may queue behind it; the spacer releases them only when it can preserve exactly one clear conveyor square between successive released boxes. The spacer does not create, delete, fill, flag, or otherwise alter boxes.
Place the Packer Block directly on a conveyor square. Wire an electrical source to IN. Each new OFF→ON pulse toggles the packer between OFF and ON. When OFF, boxes pass normally. When ON, the leading box is held while another box remains upstream and can close the gap; accumulated boxes are released as a tight train with no empty conveyor squares between them. A final solitary box is allowed to pass instead of being trapped indefinitely.
LOAD: place the Box Transfer one square behind the arriving box position, with the Box Magazine one square beyond that box in the arrow direction. Each new electrical IN pulse moves exactly one waiting box into the magazine when capacity is available.
FEED: place the Box Magazine one square behind the Box Transfer and point the transfer arrow toward the output square. Each new OFF→ON pulse requests exactly one FIFO box from the magazine. If the output square is occupied, that one request waits until the square becomes free. The actual stored box object is restored, preserving UID, fill level, color, NORMAL/FLAGGED state, cork state and future box properties.
The Box Magazine is the Phase 3 passive FIFO storage buffer with configurable hard capacity from 2 to 50 boxes. A box can be pushed into the magazine from any side. The yellow FEED IN terminal is configurable as ONE or FULL BATCH. ONE requests one FIFO release on each new OFF→ON pulse. FULL BATCH snapshots the items currently stored and dumps exactly that snapshot in FIFO order, one at a time as the output clears. The actual box object is stored, so its UID, EMPTY/FILLED state, NORMAL/FLAGGED marker and later persistent properties are preserved in order.
The display shows current stored count versus capacity plus a small contents window for the next FIFO box to leave. Edit also selects OUT direction (UP/RIGHT/DOWN/LEFT), and the BUILD chevron follows that setting. Capacity is absolute: when full, another box is refused rather than pushing any stored box out of the magazine, and the small purple FULL/BLOCKED indicator lights. The yellow FULL OUT terminal is a sustained electrical status output: it turns ON at capacity, stays ON for the entire FULL condition, and turns OFF as soon as the stored count drops below capacity. If FEED is pulsed while the touching perpendicular conveyor square is occupied, that one request waits until the square becomes free; exactly one FIFO box is then released. A held FEED signal cannot continuously empty the magazine.
The Recycling Chute removes a box that enters its square. Recycled boxes disappear from the production flow instead of being treated as normal finished output. Use it for rejected pieces, disposal paths or test arrangements.
The Routing Port is a small two-sided pass-through used to control the visual path of hoses and wires. In Edit, choose Electrical or Pneumatic. Electrical mode has yellow IN and OUT terminals and allows multiple wires into IN and multiple wires out of OUT. Pneumatic mode has two round hose sockets; each pneumatic socket may have only one hose connection. The yellow TGL terminal is always electrical: each new OFF → ON signal toggles the pass-through OPEN/CLOSED. The center ✓/× can also be clicked in BUILD mode.
Electrical terminals may be used for fan-in and fan-out: several wires may feed an electrical input and one electrical output may feed several destinations. Use this sparingly so diagrams remain readable. Pneumatic sockets are different: each pneumatic port accepts exactly one hose connection.
BUILD places and edits parts. CONNECT joins pneumatic ports with hoses. WIRE connects electrical signals. RUN operates the experiment. If something does not work, follow the circuit from its source toward its destination and use indicator lamps to expose electrical states that would otherwise be invisible.
FILL: uses its selected process time. Test fill target sets the intended final level from 1–100%; use 50% to deliberately create a PARTIAL container for testing. A nozzle never removes contents, so a target below the current level leaves that level unchanged. With fill error OFF, the nozzle reaches its selected target. At 0.5% or 1%, a rare failed fill may stop below that target. Any underfilled uncorked container can be routed through another FILL nozzle to top it up. FLAG / CLEAR FLAG: automatically process a box for one heartbeat. CORK / UNCORK: automatically add or remove the independent cap/cork state in one heartbeat; fill level is never changed by corking or uncorking. If a controlled conveyor is selected, that conveyor pauses while the box is processed and resumes afterward.