I was thinking about the sensors which I should implement on my robot. I was thinking of making a tube intake with a mecanum drive system. I’m currently using V5. We are trying to determine which sensors we will implement. Which sensors are should we use? And where should mount the sensors if I implement them? Which ones require PID? Which one don’t. And lastly, where can the sensors be used?
The V5 motors have pretty good built-in sensors, and PID controls (if used properly). However if you wish to use external sensors:
- potentiometers are good to use on arms, but be aware that they have a fixed range of rotation.
- limit/bumper switches are good to determine if something has reached the right position.
- external optical shaft encoders are good for measuring rotations of a shaft.
Shaft encoders are used for PID motion control… Potentiometers can be used with PID to hold a position of an arm… etc.
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No sensors require pid to be used. Rather pid takes information from sensors and uses it to control the motors.
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What about the gyroscope when driving? Is that something which you have implemented onto your robot?
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good point - the team did use gyro to correct turns at end of runs.
Did your team use PID feedback control to correct turns? If not what did they use?
If you’re willing to put in the time you could use 3 quad encoders and implement some odometry.
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Well using a gyro is great since u can use it to turn and drive strait
Is a header file required for every component of the robot?
No it is not required. It is just to simplify things. And this is off topic.
Sorry I forgot that this wasn’t the chat.
Nevermind just be careful
@CarCar I can understand your question. But in what way r u gonna ask like sensors are catagorised into 5 types.Tats why i ask you like is it related to motion or light detection sensor or inductive proximity sensor,based on which suggestion are taken
Got it
20 chararcters 20 characters.
All of the categories.
Sure I know what each sensor does? I just wanted feedback as to which ones should be used, and what purpose each one had in that case.
So vision sensors are hard to tune, since just a bit of lighting variant will change cause the item to be not detectable. For the bumbers, you dont really need them since they have no difference than just bumbing the wall to aling the robot. For light sensors/line trackers, vex isnt based off from line traking (fll, wro etc) so its not so practical to use them to line track. The only use of them can be to align the robot to the lines on the field or to see the color of an intaked cube. The gyro is very usefull in most cases. For the ultrasonic sensor, it can be used in pairs to align the wall at a distance insted of physically bumping the wall. However, ive test this and make sured the ultrasonic sensors are level, but the readings are far off from 5-10cm. If you want to use ultrasonic sensors, only use one of them. If you dont need to align the wall(which means you can be sure that the robot wont be misaligned at that step), just stop the robot when the sensor reads a value less than n. Or else, if you need the robot to be aligned, just first bump the wall first then stop when the readings are in the desinated range. I dont really have any experience in accelerometer, but not many teams use them. For the exterial shaft encoders and the potetiometers, the difference is that the pot is more accurate but can only rotate a certian range (250 deg) . The main difference it that the encoder can be calibriated (tare to 0) and the pot cannot. The pot is used mostly in lifts, so no matter where the lift starts(maybe u forgot to start the program with the lift at the lowest pos) it will still maintain the true value. On the other hand,if u use the encoder, the “0” position is based on where it starts, however it can be tared. Acctually, the integrated encoders are really good in acuracy and the external encoders or pots may not be needed. Lastly is the limit switch. It can be use to limit a lift, or to detect if there is a cube in the roller, or is there a ball in the catapult. Its a digital sensor which only returns one or zero and is really easy to program. The line tracker can also do this job of detecting things according to thier darck/brightness. Sorry if i miss any sensors.
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But wouldn’t the ultrasonic be inaccurate if it detects other ultrasonic sensors. Furthurmore , do the bumper switches have problems with not activating?
What do you mean? They are put side by side leveled. They are very inaccurate after i tested them. The bumper switch need a comparitively high level of force to activate them. If they cant activate, try using a limit switch. The are the same but the limit switch requires less force.