I know it's been quite a while since I've last posted but finally I have something that works well:
Here you can see it in action:
https://www.dropbox.com/s/y49mpgqedi...84622.mp4?dl=0
and Here is where it is pushing the battery:
https://www.dropbox.com/s/h8bvnyu8ui...85045.mp4?dl=0
More media... shared here via ftp:
ftp://ftp.termstech.com/LeadScrewPics/
username
sharedmedia@termstech.com
password SharedMedia!!!!
It is unfortunate that the 393 is no longer a legal motor for FRC, but we still intend to use it for another project, and intend to have it work fully with the roboRIO... there are 3 solutions we are currently exploring with that:
1. Find out what the real-world current draw of the motor is actually using and see if this is more than what the roboRIO can provide using a direct connection. I suspect it's under in most cases as it was on the Digital Side Car... but I also believe is issue is why they removed it from the list and probably won't put it back.
2. Use external battery... Vex Support has helped us find a solution that is sound. Doing this, and some simple wiring that will get the 7.2 volts we need (and correct current)... of course this would not be allowed in FRC
3. Use a custom voltage regulator with the PDP... this one seems to be the most robust assuming that we may pull more current than what the roboRIO can provide. We're looking to several possible voltage regulators and may try 2 parallel circuits of 2amp with 7 volts since these are common to find... still work-in-progress.
That said... it's back to the drawing board for FRC... we'll have to pick a motor that is on the list if we wish to have something... the problem there is the speed of the motor... so if you want to help us out... please reply with which motor you think would be ideal replacement. The ideal case is slower speed motors that have a lot of torque like the 393... from that we can try to figure out how to make it work.
This linear actuator shown here is the first revision... we intend to add the 10 turn potentiometer, and limit switches in the future revisions. Also the back half of actuator it is not shown in the picture this one spans 7 inches, but can go up to 12, by screwing on the back end of the appropriate size. It's lightweight because it is 3D printed, and very cost-effective solution. Will be nice to have something for FRC though.
