Go to Post Doesnt that sound like a McDonalds Item....Ya ill have a MacTablet with fries and a large Coke - Bill_Hancoc [more]
Home
Go Back   Chief Delphi > Technical > Electrical > CAN
CD-Media   CD-Spy  
portal register members calendar search Today's Posts Mark Forums Read FAQ rules

 
 
 
Thread Tools Rating: Thread Rating: 2 votes, 5.00 average. Display Modes
Prev Previous Post   Next Post Next
  #28   Spotlight this post!  
Unread 09-05-2012, 15:17
techhelpbb's Avatar
techhelpbb techhelpbb is offline
Registered User
FRC #0011 (MORT - Team 11)
Team Role: Mentor
 
Join Date: Nov 2010
Rookie Year: 1997
Location: New Jersey
Posts: 1,624
techhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond reputetechhelpbb has a reputation beyond repute
Re: TI and future Jaguars

Per some of the existing comments in this topic:

Quote:
Originally Posted by Al Skierkiewicz View Post
I think it is time to restate some basic principles here...
1. The resettable breakers are chosen to prevent fires on the robot. Nothing exotic about this, the current rating protects the wiring. What you choose to connect is up to you, the user. The breakers are not intended to protect a relay, a speed controller or anything else you put on the robot.
No interest in waiting for the breaker. I hope we fully intend to implement adjustable current limiting that will cut out cleanly at the limits much faster than that breaker can manage and at optionally higher limits than the Jaguar.

Quote:
2. You must consider that these devices are going to be used by inexperienced students up to and including very experienced mentors. They must be designed to satisfy both groups with ease.
As far as ease of use is concerned, given the admission of TI to members participating in this topic of the known existing short-comings I think it should be easy to start with good documentation and make the immediate change in taking responsibility to acknowledge and resolve issues actively. Far too much effort was required by existing members to realize a good list of issues positive and negative for the Jaguar. The life of this project is not predicated on the need to cover our tracks as it were.

Quote:
3. Any modular design you come up with had better be fully insulated, i.e. no exposed conducting surfaces.
Technically as the metal tabs on the existing Victor MOSFETs are exposed and very much conducting surfaces I'm less worried about the use of connectors that entirely wrap the pins like 0.1" pin header males and females. Given the existing designs of both the Victor and Jaguar use 0.1" headers (PWM, encoders, jumpers) I should think they qualify especially if the parts of the electronic motor control are literally locked together with bolts. I think we fully intend to make it entirely practical to remove those connectors and hardwire the modules together. We'll leave it to FIRST to decide if that's reasonable to allow that bit of soldering.

Quote:
4. Must use common wiring methods.
Screw terminals for the high power wires (no fancy connectors). 0.1" headers or terminal blocks for the rest as necessary. Prefer to avoid buying large quantities of terminal blocks but they do make swaps much cleaner.

Quote:
5. They must be addressable through the current hardware solution (PWM or CAN) and be capable of being commanded to make zero output from the field controllers.
Eventually I would like to have I2C or the 'custom circuit module' but for now I just want to ship what we know works with the rest of the control system.

Quote:
6. This protection must also compensate for failures in the robot driver interface(s).
FIRST's limits will be implemented in software for any interface module we make. If we do make the 'custom circuit module' it's only purpose is to impose FIRST's limits anyway. To my knowledge these limits include: maximum current, brownout voltage, field disable, in-band field disable (where applicable). The current Victors don't really offer much in these regards either...other than stopping...I think we can certainly do better than that.

Quote:
7. Above all, they must be easily inspected for conformity to robot rules.
Besides offering FIRST a 4 wire connector to verify the software and settings of the modules, I hope we fully intend to keep the enclosures for this simple and if at all possible cubic. So at most if someone wanted to see what's in the electronic motor control box it might just be easier than with the existing Jaguars. Injection molding cool looking enclosures is a nice luxury when you have the pocket for it, in this case I'm less worried about that.

Last edited by techhelpbb : 09-05-2012 at 15:25.
Reply With Quote
 


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 04:55.

The Chief Delphi Forums are sponsored by Innovation First International, Inc.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi