On FRC3005, we used black 1/8" polycarb for our antennae. There is also different colored tape on the front and back of each one so the driver can tell the orientation of the robot.
You can vary the width of the antenna to change how “floppy” they are while driving around and still making sure they are compliant enough to bend down under the low bar. Be sure to pack a few extras, we lose 1-2 per competition.
Team 423 also used “antennas”, but we accidentally made them too heavy by adding signage at the top. This caused them to constantly sag and get in the way of everything. Also, they generally cannot go up to max height because when they fold down they cannot stick out more than 15" past the bumpers. We ended up taking them off and making static PVC poles at the height limit for matches where we think there may be a vision issue. It means we lose low goal capability, but we gain vision behind tall defenses, which is much more important in our opinion.
We used painted 3/16" fiberglass rod epoxied into a stiff spring with a machined aluminum coupler. The bottom of the spring was attached to the robot frame I can try to find a photo of the mount if there’s interest;
We’re using something like these fiberglass reflector rods cut down a bit. They go into some aluminum clamps at the bottom that are all pivoted on the same screw. The outside poles have surgical tubing to keep everything centered.
I think it’s important to go with something pivoted front/back or that can’t bend sideways like those lexan strips, other wise you risk them bending sideways out of the 15". Also having 2 colors front/back or side to side so the driver will know the orientation of the robot.
I saw a team that used old halves of pool noodles - they bent when going under the low bar, and then popped straight back up. they were bright green too, easy to see
We used Orange Fiberglas arrows ($3.00 each at Dick’s Sporting Goods) with two different color fletchings. We cut the points off and epoxied to door stop springs ($1.50 for two at Lowe’s). They work great!!
I think it’s important to go with something pivoted front/back or that can’t bend sideways like those lexan strips, other wise you risk them bending sideways out of the 15". Also having 2 colors front/back or side to side so the driver will know the orientation of the robot.
Because the Lexan strips we (3005) use have 0.125" thickness in the front/back orientation and ~2" in the side to side, they have a fairly large resistance to bending in the side-to-side direction, while folding over easily in the forward/back.
If you were to grab one and forcibly twist it while pulling sideways, you might be able to get it outside of 15", but they don’t interact with the defenses that way, nor do they have enough weight to do so on their own.
Here’s some photos we snapped of 1598’s flag implementation at VADOS. Looks great to us!
2363’s flag solution really suffered when it got battered by the low bar. At our most recent event (VAPOR), about 14% of all our recorded pit activity went towards flag maintenance/repair, mostly in <5 person*minute chunks. Our drivers really liked having them though.