Simulate a Drop-off with Poster Board

Simulate a Drop-Off with Poster Board

A sheet of white poster board with a border made of electrical tape or black tempera paint makes for a handy way to simulate the drop-off presented by a table edge, with much less risk to your cyber:bot.

  • Put the cyber:bot board's power switch in position 1.
  • Run the script IR_interference_sniffer to make sure that nearby fluorescent lighting or other devices will not interfere with your cyber:bot’s IR object  detectors.
  • Make a small test patch of your paint or electrical tape on a piece of paper, and make sure that the infrared object detectors cannot see a reflection from it using test_both_IR_indicators, below.
  • Build a course similar to the one shown above.  For electrical tape, use at least three strips, edge to edge on the poster board with no paper visible between the strips, and make diagonals over the corners.  For paint, make a stripe at least 3 inches wide.
  • Use the script test_both_IR_indicators again to make sure that the cyber:bot detects the poster board but does not detect the electrical tape or paint.

from cyberbot import *

bot(22).tone(3000, 1000)

while True:
    irL = bot(14, 13).ir_detect(37500)
    irR = bot(1, 2).ir_detect(37500)

If the cyber:bot still "sees" the electrical tape too clearly, here are a few remedies:

  • Try adjusting the IR detectors and LEDs downward at shallower angles.
  • Try a different brand of vinyl electrical tape.
  • Try replacing the 2 kΩ resistors with 4.7 kΩ (yellow-violet-red) resistors to make the cyber:bot more nearsighted.
  • Adjust the ir_detect command with different frequency arguments.  These will make the cyber:bot more nearsighted: 39000, 40000, 41000.

If you are using older IR LEDs, the cyber:bot might actually be having problems with being too nearsighted.  Here are some remedies that will make it more far sighted:

  • Try replacing the 2 kΩ (red-black-red) resistors with 1 kΩ (red-black-brown) or even 470 Ω (yellow-violet-brown) resistors in series with the IR LEDs instead of 2 kΩ.
  • Try pointing the IR LEDs and detectors downward at a steeper angle so that the cyber:bot is looking at the surface right in front of it.