2018:Drivetrain

1/10/2018

Design descisions: U shaped rails to support wheels, 4 omni and 2 colson, and a 14:64 gear ratio. Goal for tonight is to get a great start on the CAD model and identify things to go on the shopping list.

Ordering pocketed gears from west coast products.

1/7/2018

After the strategy discussion, we were told to keep defense in mind along with offense, after experimenting, strategy was reassured that the drivetrain would make it up the ramp and the robot would stay stable

After lunch we conducted tests with the 2017 and 2014 drive bases with the ramp and the conduit hump and determined that the 2017 drive base as is would not work however the 2014 drive base would due to ground clearances.

Concept study on wheel height on the platform.  Verified that the base with 4 inch wheels will work on platform (included flat surface today to verify the position of the middle wheel). Also verified that the 6 inch wheel will be ok (bumper height needs to be 1.5" minimum).

modifications to the 2017 drive base to resolve previous issues

Shopping to check aluminum gear proces for Pocketed vs non-pocketed:  West Coast Products offered a pocketed VexPro Gear.  64 tooth gear cost +$4 when pocketed by WCP.  0.183 lbs per gear reduction, all 18 gears would be 3.3 lb reduction and cost $72.  Just doing the 6 gears with load will save 1.1 lbs and cost $24.  We could put holes through the non loaded idler gears to get the weight reduction without adding the cost. 

1/6/2018

Made several drawings of different sized wheels and height of the bumpers; comparing it to the ramp.

4 inch wheels and 2 inch height

6 inch wheels 1.5 inch height

6 inch wheels 2 inch height

8 inch wheels 2 inch height

4 inch wheels 1.5 inch height

We could modify last year's drive base by changing the length, and the frame height from the ground. We can adapt it to any size based on what the other teams decide they want. This was the idea has been tested already last year and we know it is fast.

http://penfieldrobotics.com/wiki/images/6/69/A001_Final_Robot_Assembly_-_Larry.png

These are our notes comparing different size wheels and sizes of things on the field to possible drive train sizes.