Draft a Junction Study
This section walks you through the process of creating a Junction study in iNode, from naming your junction to drawing and refining the boundary that defines your intersection.
Overview
The Draft Your Study section outlines the step-by-step workflow for setting up a Junction study in iNode. The process includes naming your junction, drawing the boundary that defines the intersection, and reviewing the approaches that are automatically detected within it. Each study covers a single junction. If you need to monitor multiple intersections, you will need to create a separate study for each one.
The following breaks down each step, guiding you through selecting the right boundary method and configuring your study with clarity and confidence.
To start a new study:
- Click Create New Study
- Enter a name in the Name field, or leave Auto-detection enabled to have iNode automatically generate a name based on the detected road names within your drawn boundary.
The screen below is what you will see after clicking Create New Study. The map on the right shows your available study region, and the panel on the left is where you will configure your junction details.
Drawing Your Junction Boundary
With your study named, the next step is to define the boundary around your junction. This boundary determines which roads and approaches iNode detects as part of the intersection.
You have two options for drawing this boundary:
- Draw Polygon
- Draw Circle
1. Draw Polygon
Use Draw Polygon when you want precise control over the shape of your boundary. This is useful for intersections where the approach roads are not evenly spaced or where you want to exclude nearby roads.
To draw a polygon:
- Click Draw Polygon at the top of the map.
- Click on the map to place each corner point of your polygon around the junction area.
- Close the shape by clicking back on your starting point.
The image below shows an example of a polygon being drawn around a junction area. The boundary appears as a dotted outline on the map.
Once your polygon is complete, iNode will automatically detect the road approaches that fall within the boundary. The panel on the left will update to show the detected approaches along with their lengths, and the junction name will be populated if Auto-detection is enabled.
2. Draw Circle
Use Draw Circle when the junction is a standard intersection and you want a quick, symmetrical boundary. For this to work correctly, your cursor must be placed precisely at the point where all roads intersect before you begin drawing. If the circle is too large, it may capture additional roads that are not part of the junction, which will add unintended approaches to your study.
To draw a circle:
- Click Draw Circle at the top of the map.
- Position your cursor at the exact centre point where all roads meet.
- Click and drag outward to set the radius of the circle.
- Release to complete the boundary.
The image below shows the result after clicking Draw Circle and beginning to draw. The green shaded area represents the circle boundary being placed on the map.
Editing Your Boundary
If you need to adjust the boundary after drawing it, click the Edit Boundary button at the top of the map. Depending on which boundary type you drew, the editing behaviour is as follows:
- Polygon boundary: The boundary becomes editable with draggable points visible along its outline. Click and drag any point to reshape the polygon around the junction area.
- Circle boundary: The circle is displayed with draggable dots around its perimeter. Drag any point to resize the circle. Take care not to expand the boundary too far, as iNode may detect additional approaches that are not part of the junction you are studying.
The example below shows what happens when the circle boundary is enlarged beyond the intersection: a fifth approach (Hector Ave North Bound) is picked up because the boundary extends far enough to capture that road. Make sure your boundary remains tightly drawn around the intersection before saving.
When you are finished adjusting your boundary, click Finish Editing to confirm your changes.
Once you are satisfied with your boundary and the detected approaches are correct, click Save to create the study.