Killer Max Version 2 Part II

Majority of the new chassis for the Killer Max ver 2 is finished. All the parts seems to fit as my design. However, I'm still unsure if the wheels in the front is in horizontal with the rear wheels. I plan to add shield surround my robot as well as a cannon just for a cooler looks.

The infrared sensor is installed and check with a camera for the blink light. I installed the sensor on the very front of my tank compare to others have installed in the middle of their robot.
All for motor is check and work fine. However, when i try to test it through the brain and the motor chip, i can hear a small engine sound but the wheels won't spin. I'm still wonder if it's the motor chip's problem or something else.

Saturday is the competition, which leaves only few days to fix the motor problem. I have finished majority of the programming code, what's left is to assign each of the 4 motors to the right part.