pic: Shaft Drive Bearing Blocks

[Greg Needel]

Efficiency might be your worst nightmare with this system.

Chain & Belt Efficiency ~ 95% - 98%
Spur Gears Efficiency ~ 95% - 98%
Bevel Gears Efficiency ~ 90% - 95%
Planetary Gears Efficiency ~ 80% - 90%


Efficiencies multiply for every stage in your gearbox, so for your drive you have spur>planetary>bevel(x2) assuming that your gearboxes are that the top of efficiency you would be getting .98*.95*.90*.90= ~75.4% efficient at transferring torque. This also does not take into account the effects of torsion of your drive shaft on the efficiency. I like the idea and how different it is in application, but sometimes being innovative for no reasons can have adverse effects. That being said I would love to see this drive work, but I would be hesitant to build this for the competition season without building a prototype drive in the off season.

[John C]

My team has also designed a similar system. There is one thing you may want to take into consideration. In our design we use spider couplings in the driveshaft to allow for slight misalignments in the bearing position. This was important for us because if the robot frame becomes bent slightly in any way it will bind the shaft. Ill post the drawings after our next meeting on Tuesday so you can see where they are located.

[amos229]

Great design. but if the frame flexes chances are something is gonna skip or break. plus under the tremendous forces on that shaft i doubt the bearing blocks will stay in place. If its a flat game this year then it might work but even then the robots still take alot of beating.