[Hieb]

Thank you all for the suggestions. I decided to do two things - I started with fresh code and I unplugged all of the pwm's and re-added them 1 at a time. My 4 drive motors are now operating properly without pulsing. I wasn't able to isolate the exact cause of the problem, but I have a functioning, drivable robot and can now begin working in additional functionality (compressor, launcher, grippers, etc.).

Thanks again.