[month] [year]

Shashank Srikanth – Dual Degree CSE

Shashank Srikanth received his MS  Dual Degree in  Computer Science and Engineering (CSE). His research work was supervised by Prof. Madhava Krishna. Here’s a summary of Shashank Srikanth’s thesis Intermediate Representations for Trajectory Forecasting as explained by him: 

In urban driving scenarios, forecasting future trajectories of surrounding vehicles is of paramount importance. It is an essential component in the autonomous driving pipeline as the forecasted trajectories are used as inputs in the planning and control modules of the autonomous vehicles. While several approaches for the problem have been proposed, the best-performing ones tend to require extremely detailed input representations (e.g., image sequences). As a result, such methods do not generalize to datasets they have not been trained on. On the other end of the representation spectrum, some approaches represent the vehicle of interest in a scene in terms of geometric properties such as 3D location w.r.t ego vehicle, rotational parameters, and velocity. These approaches suffer from a lack of semantics / contextual information and cannot produce the most accurate forecasts. In this thesis, we propose intermediate representations that are particularly well suited for trajectory forecasting. We show that these intermediate representations, generated using off-the-shelf computer vision methods for object detection and semantic segmentation, provide the right balance between competing features of expressiveness and generalizability. As opposed to using texture (color) information from images, we condition on semantics and train an autoregressive model to accurately predict future trajectories of traffic participants (vehicles). We demonstrate that semantics provide a significant boost over techniques that operate over raw pixel intensities/disparities. Uncharacteristic of state-of-the-art approaches, our representations and models generalize across different sensing modalities (stereo imagery, LiDAR, a combination of both), and also across completely different datasets, collected across several cities, and also across countries where people drive on opposite sides of the road (left-handed vs. right-handed driving). We also conduct detailed ablation studies to understand which semantics generalize across datasets and demonstrate their importance in the generalizability of the model. Additionally, we demonstrate an application of our approach in multi-object tracking (data association).