Apologies if this question has been answered before or is the wrong 
question or something. I am not an expert in this area.

We would like a controller for a robot with car-like kinematics. DWA and 
trajectory rollout assume that the robot can have an
independent rotational velocity but this is not possible in our robot. It 
is 4-wheeled and has a steering angle for the front two wheels which 
controls the change in heading in conjunction with the forward velocity. I 
already have a high level planner for generating a plan from init to goal 
based on an A* like algorithm but we need a low-level controller. What is 
the best solution using ROS?  Should I modify DWA /TR so that it can
sample trajectories with car-like dynamics? Is this already implemented 
somewhere?

Thanks,
~Deepak