So our robotics organization is in our second year and quite inexperienced. Our team sees how important skills runs are. We noticed during Auton skills, due to inconsistent interactions with the tribals into the goal, some type of movement tracking would be necessary to have an effective and consistent autonomous, especially in skills. We don’t have any axle encoder, and odometery is a bit above our skill level for coding seeing as we are still using Block Code. Would inertial sensors be the most effective for this? Or is there more of a consistent and simple way.
Sure. Inertial sensors would certainly be effective here.
If you have not done this already, make sure that whenever you command your drivetrain to turn, you use the “turn to heading” block (or similar) This will turn your robot relative to a global heading. This global heading should change very little, even after extreme interactions with game elements and field obstacles.
One potential method to counter this would be a GPS reset. While the GPS is incredibly inaccurate when the robot is moving, it can give you a very good idea as to where your robot is if given 1-2s where the robot is fully stopped to retrieve a position. This would be best used if you were to drive over the bar and straight into the goal, as your angle could be held relatively constant. However, time is precious, so it really comes down to what risks you’re willing to make with time.
Thanks I haven’t been doing this and it will certainly help. I have to take a 2 week long break from working on the bot but when I get back I’ll test if I still even need the inertial sensor
The VEX “GPS” system requires a $200 sensor. You plug it into your robot, and a camera embedded in the sensor repeatedly takes snapshots of the field wall. If you have the GPS strip attached to your wall (a black and white checker-y patterned strip), it can do some Fancy-Dancy post processing on the image-snapshot by observing the shape of the GPS strip on the wall to determine where your robot is.
In your code, you can access this position as an X,Y coordinate and a Heading value.
If the GPS sensor is close to the wall, the image of the GPS strip will be larger than if the sensor was far away. There is a lot more to it than this – stuff that goes waaayyy over my head – but lucky for you, you don’t have to understand it. They understood it for you!
Thanks @Pi_way, our school definitely can’t afford this but I think I’ve gathered enough info from this thread to improve our autonomous skills by atleast 40 points.