Rookie Team needs help with D-Link and arm design

We hooked up the D-Link to the power distribution board with a 12V to 5V converter in between as suggested in the diagram from the first website. However, the D-Link didn’t power up when we plugged in the battery, and it smelled like the D-link burned up. We suspect we might have plugged it in backwards. But anyways would that be the right way to connect the D-link if we were to plug it in the right direction?

Also, we began designing our arm, and we came across this design.

What would be some of your suggestions if we were to go with this design?

Thanks

How do we go about making that arm very simply as 10 students with no engineers and in a 3 week span

Everything takes longer than you think it should - even for veteran teams. Take stock of where you are with your robot and what is left to do. Prioritize what must be done and what you would like to do. It’s perfectly okay to do a very basic robot in your rookie year - this may mean a robot with no arm. My guess is there will be a lot of game pieces tossed onto the field and a pusher robot may be able to heard them to the scoring area for alliance partners to score.

If you decide to do an arm there are a lot of details to work through. How high do you want to reach, how fast should it move, how much will it weigh, what type of drive system, how to connect up all the different parts of the system. This may be a good excersize even if you don’t have time to finish. By working through the details as far as you can get you’ll be in a better position for next year.

As far as the D Link goes, you would have had to cut the AC adapter off of the wire and make sure to hook the positive (+) wire from the D Link to the positive wire from the converter and the negative (-) wire from the D Link to the negative wire from the converter. Also, make sure the positive input wire to the converter is hooked to the 12 V + out, and the negative converter feed wire is hooked to the 12 V - out.

The Dlink is not reverse power protected (positive and negative reversed) and is not capable of withstanding input over 5 volts. Although these are available, I have been told that Best Buy does not stock them.

My offer to come for a visit still stands. Just let me know.

We have decided to build a small arm that is capable of picking up the tubes for teammates to score and maybe even scoring in the autonomous round. However, we are not sure of which motor(s) to use for the arm. We are considering the DC motor that came in the Tetrix box or the window motor. Which one would be the better for the arm?

The window motor wins by default, because the Tetrix motor is only legal for use on the MINIBOT.

the window motors are your best bet, one reason is that you can put one on both sides of any kind of tower you have, this will make it less likely that you need further gear reduction. for a very basic arm i would recommend 2 window motors, the black plastic hubs that come in the kit fit on their default output gear, and they are unlikely to give you problems with back-driving.

FIRST of all, the fact that your team found this forum is really good. Our team didn’t find it until our second year out, and we would have been so much better off if we had seen it our first year!

I couldn’t get to the youtube video you posted, so I’m not sure how helpful this will be.

Team 2980 has gone completely open source. We would be happy to share our CAD files as well as any pictures or information on how we are building our robot in order to help other teams, especially rookies.

Here is a link to our thread.

We will also be posting tutorials on our robot over the next week. Especially relevant is how we mounted the windshield washer motor.

http://forums.trossenrobotics.com/gallery/files/1/4/9/9/2011share_-_3.jpg There are pictures showing how to make this on the above mentioned thread.

Finally the connectors for the window washer motors. Another person posted a link to where to get them on this forum. The website is www.mouser.com and the product number is 829-12129487. That is for the plastic shell. There are also little metal pins that you have to put in there. 12129493. The total cost for these connectors will run you about $2 a piece.

If you have any questions feel free to contact us via PM.

Edoga