Designing with Slope-IQ

The Slope-IQ design dialog opens automatically after you save a survey, or when you tap the Slope-IQ button in the Survey sidebar. It has a chart on top, six parameter cards in the middle, a stats strip below them, and an Implement Slope button at the bottom right (next to Cancel).

Three design modes (top of the dialog):

• Best-Fit — automatic. The app hugs the terrain as closely as possible while always going downhill. This is the default and usually correct.
• Guided — you tap terrain points on the chart to mark them as control points. Slope-IQ joins your control points with straight grade segments and respects the Min Grade between them.
• Freeform — you tap anywhere on the chart to drop control vertices, drag them around, tap to delete. No grade rules — pure straight lines between vertices.

Outlet direction

The toggle in the top right reads Outlet: Auto by default. The inlet is the higher-elevation end of the survey; the outlet is the lower-elevation end. Auto-detection compares the first and last survey points: if the last point sits lower than the first, the survey is treated as inlet → outlet; otherwise it's flagged as reversed. Tap the toggle to Outlet: Reversed if Slope-IQ guessed wrong and the ditch actually drains the other direction. The chart redraws. The toggle is hidden in Freeform mode because you place the vertices yourself.

Undo (Guided and Freeform)

In Guided mode an Undo button removes the most recently added control point. In Freeform mode it removes the most recently dropped interior vertex (start and end vertices are protected). Disabled when there's nothing to undo.

Parameter cards

Each card has a label, a current value, plus and minus buttons, and (most importantly) the value itself is tappable — tap the number to bring up a numeric keypad and type any value directly. Use ± for fine tuning, tap-to-edit for big jumps.

• DEPTH OFFSET — how far below the surveyed ground the target line sits. Default 0″. Range is wide (±360″ / ±915 cm) because excavator and big-scraper jobs sometimes need a 20-foot offset. Most ditches use 0 to 24″.
• MIN GRADE — the minimum drainage slope, in percent. 0.05% is standard for surface drainage. Smaller values let Slope-IQ hug the terrain more closely. Bigger values force a steeper, straighter line.
• BOTTOM WIDTH — the flat bottom of the trapezoid cross-section, used only for the cut-volume number. Default matches your Implement Width in Settings.
• SIDE SLOPE — the H:V ratio of the ditch sides (also volume only). Default 6:1.
• MIN DEPTH — visualization-only minimum cut depth. Stations shallower than this get red shading on the chart but the design line is unchanged.
• MAX DEPTH — visualization-only maximum cut depth. Stations deeper than this also get red shading. Set 0 to disable. Range up to 120″.

When you change a card, Slope-IQ recomputes immediately and the chart redraws.

Stats strip below the cards

Read this to confirm the design makes sense before tapping Implement:

• Grade — overall percent slope from inlet to outlet.
• Max Cut — deepest point on the design.
• Avg Cut — average cut depth across stations that are actually cut (skips fill).
• Length — total ditch length.
• Drop — elevation drop start to end.
• Cut Vol — estimated cut volume (cubic yards or cubic meters), based on bottom width and side slope.
• Est. Passes — how many passes the deepest cut will need at your current Max Cut Per Pass setting. If this reads "Est. Passes: 4 @ 2″/pass" and your scraper handles bigger bites, raise Max Cut in Settings or in the Auto-Nudge prompt.

Tapping Implement Slope:

1. The app prompts for a design name (default uses the survey name plus "(Ditching)"). Type a name and tap Save & Implement.
2. The design saves to disk, the Grade screen opens, and the design loads.
3. If a benchmark prompt appears, follow it.
4. If an Auto-Nudge prompt appears, choose Enable Auto-Nudge for deep cuts that take more than one pass, or Use Manual Nudge for shallow single-pass jobs.