Advertisements

Tour Easy Daytime Running Light: Now with Chirality!

In the unlikely event our bikes need two running lights or, perhaps, a running light and a headlight, the solid model now builds mounts for the right side of the fairing, as before:

Fairing Flashlight Mount - Right side - solid model

Fairing Flashlight Mount – Right side – solid model

And for the left side:

Fairing Flashlight Mount - Left side - solid model

Fairing Flashlight Mount – Left side – solid model

Ahhh, chirality: love that word.

Those pix come from a cleaned-up version of the OpenSCAD code that finally gets the 3-axis rotations right, after a rip-and-replace rewrite to deliver the ball model with its origin in the center of the ball where it belonged and rotate the ring about its geometric center. Then the rotations become trivially easy and a slight hack job spits out a completely assembled model:

if (Component == "Complete") {
  translate([-BracketHoleOC,0,0])
    PlateBlank();
  mirror(TiltMirror) {
    translate([0,0,ClampOD/2]) {
      rotate([-Roll,ToeIn,Tilt])
        SlotBall();
      rotate([-Roll,ToeIn,Tilt])
        BallClamp();
    }
  }
}

However, putting the center of rotation directly over the center of the base plate means the ToeIn rotation shifts the bottom of the clamp ring along the X axis, where it can obstruct the mounting holes. Shifting the ring by a little bit:

ClampOD*sin(ToeIn/2)

… keeps the ring more-or-less centered on the top of the plate. That’s not quite the correct geometry, but it’s close enough for the small angles needed here.

Aiming the beam slightly higher makes a 400 lumen flashlight about as bright as any single LED in new car running lights:

Fairing Flashlight Mount - Mary approaching

Fairing Flashlight Mount – Mary approaching

You can just barely make out the snazzy new blue plate on the left side of the fairing.

A bike’s natural back-and-forth handlebar motion sweeps the beam across the lane, so I think there’s no real benefit from blinking.

The OpenSCAD source code as a GitHub Gist:

Advertisements

, ,

  1. #1 by Daniel B. Martin on 2017-08-24 - 07:44

    Chirality. Thank you for improving my vocabulary.

    • #2 by Ed on 2017-08-24 - 09:04

      It’s not a word used in polite conversation … [grin]

Spam comments vanish. Comment moderation may cause a delay.

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s