Well, we had a whole different array of sensory at one point or another. I think the most unique sensory we had was our chain sensory. We too a plastic cup (I think) and wired an led beneath the chain, and a small light sensor above the chain on the other side of the cup. This would click on and off every now and then from the links in the chain blocking the path of light. Well, this was used in our auto to double check whether our drive was stuck or not. It worked ok, but we didn’t have enough time to really sit down and get it going before competition.
We also had a small “batvision” module.
Our plans were to mount two ultrasonics on two servos, and have it pivot around, scanning in front of the bot.
This data would be picked up by the dashboard output by our laptop, and we were working on a 3D program that had a mesh of the field and the bots. We would have these transparent "walls
" pop up where the bot had gotten feedback, and the distance it had received it. I really wish that one flew…
We also tried using a magnetic switch mounted by each wheel, and tried gluing magnets around the wheel to count the rotations. We didn’t get too far with that one either.
We DID have a successful line-tracker, but as everyone knows, it was just TOO slow.
This year we hope to implement the gyro in some way. I think the one we received last year was a dud too, we couldn’t get it to work right.
The sensory you use really depends on your system, and a good collaboration of hardware and software.
If your’e using a skid steering bot, then you pretty much just need a way of checking your wheel rotations. You could rely on software for the direction, but it’d be a little trickier.
Anyway, you’d be surprised how much “basic” sensory can do, switches and the like.
Keep in mind however:
The More Data you gather, the more you can compare against each other (triangulation, sort of), so the more sensory, the better.
The way I like to think of choosing sensory is this:
For last years game, we gathered the team into one room with no windows. It was a pretty large room, and there were things in it (furniture, etc.) We took a bell and put it in the middle of the room. The bell represented the Stacks up on the ramp.
Then, we tied everyones arms behind their backs, so they couldn’t feel anything, we turned off the lights, and they had to start around the edges of the room. The also weren’t allowed to make any noise, or they got dq’d. They had to try and ring the bell in the dark. Anyway, this gave them some perspective on what it’s like to be the robot. You can’t see, feel, or hear anything. You may not even know where your target is. There was one thing I pointed out though:
Everyone DID know in which direction their feet were moving, and they knew if they ran into something. This helped a little.
We found pretty quickly that certain things can make the job easier.
Anyway, It’s really 50% robot and game specific on what kind of sensory you choose. Just explore!