notafraidtotry said:Hiorth said:Just posted some illustrations of our 3d models here, will continue to post updates as we go forth. https://www.facebook.com/media/set/?set=a.10159438659855144&type=1&l=2e97c1f9fb
Cheers
They look great.
We are still working on various drive options. I have updated the parts list based on feedback here but the plan will be to ensure we can test different drives but keep the same electronics, batteries etc.
The OpenROV teams use bog standard out-runners sprayed with silicon spray before each dive and rinsed with fresh water. Sync issues are a possibility but seem to be when you use too large a prop and the ESC expects to see higher speeds. I'm still tempted to try this approach out but guess the in runner and gearbox route will be the best and is of course tested. The gearboxes just seem to be very expensive.
I have even started looking at the large professional cordless drills. My hope is still to find something that already exists that can be re-purposed. You can get used 36V cordless drills without batteries for under £50. The Dewalt DC900 for example is brushless (motor may or may not be usable) but the planetary gearbox is all metal. Output speed is 1,400 RPM with the motor running at around 22,000 RPM so getting into the right ballpark. These things retail at well over £500 new so they are well made. The clutch can be locked out although might be useful.
Anyone looked at using them?
We have looked into using a cordless drill planetary gear, the main issue we ran into is that the drill motor has a pinion gear directly mounted on the drill motor shaft. So if you are going to use your own motor, you will have to get a special made pinion gear (assuming the one on the drill motor shaft does not fit your motor shaft). All in all I belive the solution will not be as good (if you change the motor) and total cost will be more or less the same as buying an in-line gearbox (200Euro), that has a shaft clamp on the input side.
But If the motor from the drill works, then It could work well, as long as the Diameter is not to large (drag).