How to Retrieve Speed Limits for Lane Groups from the HD Live Map Catalog
Title
How to Retrieve Speed Limits for Lane Groups from the HD Live Map Catalog
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Applies To
HERE HD Live Map Catalog
Lane attributes layer
Speed attributes layer
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Summary
Speed limits in the HD Live Map Catalog are provided at road (link) level, not at individual lane level. To obtain speed limit information for a specific lane group, the data must be resolved indirectly via the associated road links.
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Answer
The HD Live Map Catalog does not contain speed limit values at lane level. Speed limits are stored at the road link level within the speed attributes layer. To determine the applicable speed limits for a lane group, you must identify the road links associated with that lane group and then retrieve speed limit data for those links.
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How to Retrieve Speed Limits for a Lane Group
1. Identify the lane group
Retrieve the lane_group_ref value from the lane attributes layer.
2. Resolve associated road links
Use the lane_group_ref to obtain the connected road link IDs from the lane road references layer.
3. Retrieve speed limits
Query the speed attributes layer and extract the speed_limit object using link_local_ref (which corresponds to the road link_id).
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Expected Behavior
Speed limit values are returned at the road link level.
Lane groups inherit applicable speed limits through their associated road links.
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Unexpected Behavior
Expecting speed limit attributes directly on lane‑level features will result in no data, as this information is not modeled at lane level.
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Impact
Understanding the data model prevents incorrect assumptions about lane‑level attributes and ensures correct extraction of speed limit information for lane‑based use cases.
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Validation
To validate the results:
Confirm that the resolved road link IDs match the intended lane group.
Verify that the retrieved speed_limit values are present in the speed attributes layer for those links.
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Notes
Lane‑level speed limits are not supported in the HD Live Map Catalog.
Speed limits are defined once per road link and apply to all associated lanes unless otherwise modeled.
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Related Information
HERE HD Live Map Catalog documentation
* Lane attributes and speed attributes layer references
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Keywords
HD Live Map, speed limits, lane group, road link, speed attributes, lane attributes