Guided obstacle avoidance robot

Sorry for the vague title, I don't really know what to call this thing. Anyways, I was wondering how you would go about making an advanced obstacle avoiding robot. Basically, I want the robot to be able to maneuver in a fixed pattern like this while avoiding obstacles in the way.

The end result should look sorta like this. The red line is the path, and everything else is obstacles.

What kind of sensors would be best for detecting irregular objects? Ultrasonic, IR, or touch?

What have you got so far? Have you thought about what sensors you will use? Can you make a bot follow a line without the obstacles? That would be the first step. There are thousands of tutorials online for building line followers with Arduino. Have you looked at any of those?

You kind of showed up here with nothing. Do you want someone to just give you a complete solution? Ask in Gigs and Collaborations and someone will do it if you offer up enough money.

Sorry about that. Currently, my robot only has remote control capabilities and I am familiar with and have built line following robots. This is more a solution looking for a problem than the other way around so no I'm not going to have somebody else do it. As for the sensors, that was what I was asking because each has its own shortcomings. Would it be best to figure out how to setup a Kalman filter or some sort of sensor fusion? Basically, it is acting like a more intelligent Roomba. I'm not so sure how building a line following robot would help.

I'm not so sure how building a line following robot would help.

I thought you said in the OP that it would follow the red line.

No, I am just saying it would move like that in a sort of zig-zagging way, and the line was just to show that because the picture explains it better. So it has a "preset" path that it tries to stick to while still avoiding obstacles along the way.