HRVO not work well

[Tsao666]

Hi, I'm trying to modify Hybrid Reciprocal Velocity Obstacle(HRVO) to fit my task. However, I found that if start and goal set as straight line (like start, goal = [25, 10], [25, 40], or start, goal = [10, 40], [40, 10]), the path will not go straightly without other obstacle interfere. Can you explain why and how to solve? thanks a lot!

(This gif just show the straight line path with HRVO algorithm)