We have two possibillites for an extending mechanism: Tape measurer, and a powered car antennae. Preliminary tests showed that the tape measurer can extend roughly 18 inches before a collision event will deform the tape measurer (it won't snap back).zThis is in free space.

• When constrained against the floor, any length will snap back into place
• More oblique the angle, the more compliant tape will be.
• time to max extension (36 inches at ~ 6 volts-battery) ~2.7 secs.

Another component is to have a switch at the end of the tape measurer to registr a hit. This means we have to run wires out to the end. this means we have to unspool wire

For this design, the wire literally springs off the spool. However, there is often a tangle. Recommend making wire signifiantly longer than required distance. Also, wire winding should start at base, then move to tip. Think triangle shape spool of wire inthe end.

-- SamsonPhan - 20 Feb 2009

• DSC00026.JPG:
  

• DSC00027.JPG:
  

• DSC00028.JPG:
  

• DSC00029.JPG:
  

-- SamsonPhan - 22 Feb 2009b