The Hitec HS-81
will not work for the robot wheels cause the datasheet says its not modifiable for 360 degrees. It will work for the scanning sharp IR since it should not be modified for that.
If you use a different servo, you may need to tweak the signal pulse width a bit.
For example in my code, if you see
you might need to change it to say
or something like that until the servos do what you want.