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dddriveman
04-19-2004, 08:39 AM
While talking to the innovation first guy at the championship event he said that they are going to switch to new robot controllers and operator interfaces that use digital controls. He said that they are aiming at something that will use like PS2 controllers. He said that they are going to have to use lots of code to filter out the sensativity of the sticks on the controllers. What do you think of this? :yikes:

Ian W.
04-19-2004, 09:01 AM
I doubt anything on new controls. We used the old PBASIC ones for a few years, I assume we'll stick with these new C ones for longer.

I'd also be very much against all digital controls, as driving with analog controls is a lot easier, unless you like DDR or something like that.

Also that PS2 controller rumor has been around for a few years as well. I prefer the old joysticks, I've been using the same ones for three years now (literally, the same two joysticks from my team's rookie year).

Tom Bottiglieri
04-19-2004, 10:29 AM
using digital controls would just make programming harder, and wouldnt really give that much of an advantage. Plus, this probably wouldn't fly with FIRST. Dean Kamen made a it a huge point in his "homework" to make it as easy for rookie teams as possible. Rookies have a hard enough time programming as it is, and this would probably just make it worse.

JBabbie
04-22-2004, 10:18 AM
I highly doubt that they will use a different kind of controller next year. especially since not many people are complaining about the ones we have now. personally , I like what we have now.... only problem I had with controlls was the hat on the new joysticks breaking.

MikeDubreuil
04-22-2004, 10:55 AM
While talking to the innovation first guy at the championship event he said that they are going to switch to new robot controllers and operator interfaces that use digital controls. He said that they are aiming at something that will use like PS2 controllers. He said that they are going to have to use lots of code to filter out the sensativity of the sticks on the controllers. What do you think of this? :yikes:

Here's my problem with switching to new controllers: the analog to digital conversion has to happen somewhere. It's currently very easy for teams to interface an analog sensor with the controller because A/D happens in the controller. We're definitely not loosing analog sensors.

If your rumor is true, we would have to use additional circuitry to do the analog to digital conversion outside the box . Then in software we would have to combine multiple digital inputs to create a binary value to represent the analog signal. I'm not against it, it would even give more options; but it would make things a little more difficult.

The robot controllers becomes a lot simpler this way. They could use only 1 pin for each input (since we share a common negative you really don't need a negative pin).

Perhaps IFI is creating external A/D modules for us, like how they moved the relays off the robot controler to the SPIKE?

EDIT: Unfortunately, this does mean that we would need 8 pins (2003) or 10 pins (2004) to represent a single analog value.... I'm not sure how easier this would be :rolleyes:

seanwitte
04-22-2004, 11:09 AM
using digital controls would just make programming harder, and wouldnt really give that much of an advantage. Plus, this probably wouldn't fly with FIRST. Dean Kamen made a it a huge point in his "homework" to make it as easy for rookie teams as possible. Rookies have a hard enough time programming as it is, and this would probably just make it worse.

It wouldn't change the programming at all because it only affects the OI. The RC doesn't know (or care) how the inputs are processed by the OI. The only difference in the physical interface is that the OI shifts in digital bits instead of converting analog signals before sending the packet to the RC.

If they keep some of the analog ports but add a PS2-style digital port it would open it up to some really cool stuff. If you emulate the PS2 data transfer protocol (synchronous serial) using a PC or a uP you'd be able to interface ANYTHING to the OI.

<edit>
A Playstation controller interface only uses four pins: Attention, Clock, Data, And Command. The data is shifted out one bit at a time arranged in a six byte packet. There are two bytes for all the buttons and two bytes for each of the analog joysticks. It would make it difficult to add switches or pots unless they provide some analog inputs as well.
</edit>

Gene F
04-22-2004, 12:26 PM
What I heard was that the only thing they were looking to change was the joy stick interface. It is becoming very difficult to find analog joy sticks any more (the ones with the DB15 donnector), they are all USB these days. To give teams more options they are looking into adding the ability to use USB joy sticks for the OI. The values we would see at the RC would still be numeric values inducating position of the stick.

aaronbr28040
04-22-2004, 12:49 PM
It's not that hard to use a basic stamp to break the ps2 data down. There was an article in Nuts and Volts a while back on how to do this.......its still available online if you hunt for it. All of my info on it is located down in the lab but I have the basic code that is used to break it down. Although it wouldnt be THAT extremely challenging I dont think that FIRST would really change to something that would make it that much harder for new teams. The analog joysticks keep things pretty simple for beginners and allow enough for experienced teams to use as well.
-Aaron

Astronouth7303
04-22-2004, 02:15 PM
Plus, it's easy to make your own box.

(For anyone you can't find an analog joystick: eBay. here's one for a buck (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=42306&item=3475309545&rd=1))