http://www.vexrobotics.com/vex-sensors-products.shtml
I was wondering, has anyone used these sensors and how well do they work. Are they worth it?
Thanks everyone,
-rc
Which sensors are you talking about?
The mechanical ones (Bump, limit switch, etc…) will probably wear out more quickly then higher quality ones. They are also way overpriced :yikes:
I was talking about all of them, which ever ones anyone has experience with. The pricing is fine for us because we have level one and two robotics class which gets extremely awesome discounts.
We at Team 100 are using one of the line trackers to measure the speed of our shooter roller. We have the edge of our top roller painted half black and are using the sensor like an optical encoder. We’ve set up some LabView trickery to measure the time between the “pulses” of black and white and use that data to determine the rotational speed. There were a few programming kinks to be worked out, but the sensor worked as intended.
Early in the season, we tested a few other of these sensors (I believe it was only the limit switch and the ultrasonic sensor). We were able to successfully read their inputs on our cRIO test bed platform.
Team 1675 has used VEX quadrature encoders for the past two years; last year for our mecanum drive-base and this year for traction control. We’ve had a bit of trouble programming them (encoders) due to lack of experience with the new control system (we’re using C++ and can’t figure out why we’re not getting period from our encoders). Othwerwise, the protective housing is a nice feature. I recommend their use.
Vex sensors are nice for the most part. They’re already wired for a PWM signal (the pins have to be changed to female though) which is really nice and they’re fairly accurate for the most part.
The Encoders are pretty good from what I remeber, The line followers are really nice, the light sensors are kinda hit or miss, and the Ultrasonic Sensors are good to about 5 or 6 feet reliably.
As for the Limit Switches, they’re good for small applications but I would make sure they’re very well protected. The Bumper Switches are really nice though, I’ve never broken one and I’m not nice to my Vex stuff.
I’ve never used any of the never stuff like the Potentiometer or Accelerometer but they should be pretty nice.
The quality on VEX sensors is great actually…if used properly. The only ones I’ve have problems with are the bumper switches. Depending on the application they last as long as you want. We also get a discount because of our robotics classes, so the price thing isn’t applicable to most teams.
I’ve tested limit switches on lifts before (frc) and they’ve worked well. The function was that when the lift hit the limit switch coming down it would trigger a shooter for the home made game we were playing.
Btw RC, you could’ve just continued in your original thread…
I could’ve and should’ve.But didn’t, i should’ve used the search toolbar feature. Dang the build season.
Team RUSH, frc27, is using the Vex Encoder for traction control.
We have also tested the potentiometer and IR sensor, but are not currently using them on our bot.
So far I’m very happy with their performance. The output of the encoder is not as clean as the Grayhill or US Digital versions we have used in the past, but they are reasonably priced, easy to get and very easy to interface with.
Highly recommended.
In 2006 we used several of the Vex ultrasonic sensors and they seemed to work pretty well(even after getting fairly beaten up.)
We are using 3 Vex encoders on this year’s robot (2 for traction control, 1 for our turret). No problems thus far (though we did accidentally wire one backwards on our twin, resulting in a $25 red plastic paperweight).
We were considering using the VEX ultrasonic this year. It was essentially hassle free to connect and program. Fairly accurate too!
We used the Vex ultrasonic last year to sense when we could pick up a ball, a micro switch for fork placement and the encoder attached to a Vex wheel for measuring distance for the autonomous section.
This year we are using the Vex pot as the sensor on where our shooter is postitioned. I have a quad encoder to test next week, it may become our position device.
I like the Vex senors since they come with mountings and are a little more forgivable to abuse. It’s also a never ending source of amusement to me to have “little bot” components on the “big bot”.
I’ll sell you all the Vex quadrature encoders you could ever want for only $20 each!
Unfortunately, IFI will sell you the same part for $10 each: http://www.vexrobotics.com/vex-robotics-optical-shaft-encoder-kit.shtml
In 2006 381 used a VEX ultrasonic sensor and it worked perfect. Those sensors are definitely a nice resource for FRC bots.
We used limit switches for a reset to 0 for our encoders on our lift.