TOIs are a novel way of looking at traffic data, enabling deeper insights useful for traffic safety, fleet management, or autonomous vehicle development.
Just this past week — at the Automated Transport Symposium, part of SAE International’s key industry conferences — Streetscope’s CTO and Co-Founder, Erik Antonsson was on stage speaking about Safety Assurance and the demand for context-aware measurements.
For Streetscope, this tenet of understanding scenarios in traffic and consequent vehicle hazard is core to our story and embedded into our platform capabilities. How so?
Welcome the TOI: Traffic Object Interactions
This past spring, Streetscope introduced Delta, the latest evolution of our safety measurement platform—engineered to boost efficiency, streamline usability, and deliver actionable insights for our users.
One of Delta’s standout new features is its ability to automatically classify Traffic Object Interactions (TOIs). This is a sophisticated approach to traffic analysis that opens up new opportunities for our customers.
What is a TOI and What Does it Measure?
Our data stream tracks and calculates the speed and trajectory of every traffic object in a scenario relative to the ego vehicle. TOIs allow us to categorize these trajectories into foourteen distinct categories, grouped into five subclasses:
Why Are TOIs Important?
At Streetscope, context is everything. Our proprietary SHM measure has always gone beyond conventional accelerometer-based data, offering precise calculations of the trajectory and speed of every object in a scene. This delivers a wealth of detail far beyond simply recording driver actions like acceleration, braking, or swerving that might populate a TTC metric.
SHM is a composite measure that considers every interaction (and its type), providing a holistic and contextual view of any traffic scenario. With TOIs, we’re adding a whole new dimension of data — objective, quantifiable, and comparable across scenarios — unlike the manual video review processes still used by many telematics providers.
Where Else Can Customers Find TOIs?
Cataloging trajectories might sound straightforward, but our platform is the only one delivering this level of data at scale and at 30 frames per second. This granularity matters — enabling detailed, real-time analysis that no other toolchain currently offers.
While there are advanced 3D object tracking and motion analysis tools in the market, including those leveraging graph neural networks and spatio-temporal dependency modeling, none offer an out-of-the-box, scalable solution for automatic TOI classification at the granularity and frequency that Streetscope delivers. Competing systems typically require significant customization or manual intervention to classify interactions into actionable scenarios.
TOI Use Cases
TOIs are not more data for data’s sake. We believe TOI classifications open up a new analytical world for our customers, in particular those who like to dig into the details and compare projected traffic scenarios to real-world evidence (can you say ground-truth?)
For example, when studying Hotspots (another feature of our platform), it is now possible to discover (and quantify and compare) what type of interactions are creating issues. In a “normal” world, in particular while driving in highways within stop n’ go traffic, the expectation is that the majority of high SHM interactions would be of the type “Same Direction-Rear End”. But what if there’s a spike of “nervous” traffic, with drivers in front constantly switching lanes?
TOIs exist to deliver this type of nuanced view to actual traffic scenarios. Or what about dangerous intersections or parking lot exits? Will we find a spike in T-Bone interactions?
Lastly, knowing the trajectory and speed of vehicles before an incident is invaluable for much more than accident reconstruction. Here are just a few additional applications:
Ready to See Streetscope’s Platform in Action?
Our automated TOI classification isn’t just a technical breakthrough — it’s a powerful tool for anyone seeking deeper insights into traffic safety, fleet management, or autonomous vehicle development.
Want to see how Delta can transform your traffic data analytics? Get in touch today to schedule a demo and experience the future of traffic intelligence.
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Original photo by Joey Hopkins on Unsplash
