Concept design for a bike-light that projects a grid on the ground, highlighting bumps/holes

A team from the University of Sichuan won the Red Dot Design award for a concept design called "Lumigrid" -- a bike-light that projects a grid on the ground ahead of the rider, making terrain irregularities easy to spot:

Lumigrids can project a grid onto the ground. On a flat road surface, the grid will consist of standard squares. On a rough road surface, the grids will deform accordingly. By observing the motion and deformation of the grids, the rider can intuitively understand the landforms ahead. In addition, the luminous grids can make it easier for nearby pedestrians and vehicles to notice the bicycle, reducing the likelihood of collision.

Lumigrids can be fixed onto the bicycle’s handlebars. Its power is supplied by either an internal battery or by the rotation of the bicycle’s wheels. It has only one button so that the rider can easily use it while riding. The first press will turn on the power, the second press will change the mode of projection, and holding the button down for two seconds will turn the power off. Lumigrids has three modes with different grid sizes that can be used to adapt to different situations: normal mode (140x180mm), high-speed mode (140x260mm), and team mode (300x200mm)."

Lumigrids (via OhGizmo)



    1. “concept that could use some help with its technical challenges” describes a lot of the stuff on yankodesign :-)

      1. Or see

        It’s of limited use, as article points out, but they do at least have a working prototype on a bike.

  1. Also: the bike is just a simple cylinder until you grip it in both hands, at which point it forms around your body. Unfortunately the bike also creates an impermeable two-dimensional barrier in your wake that could be a collision hazard for other cyclists.

  2. Given that the angle of projection will be very similar to the angle it’s being viewed from, won’t any distortion of the grid be misleadingly minimal?

    1. I think that was the general consensus when I saw this posted on Reddit this morning. 

    2. Red Dot website seems to be down so I can’t check, but it looks to me like the grid is far too small and close to a) let me spot a hazard as it crosses the grid or b) take action having seen it.

      1. That would be my concern too.  I think if you mounted it far enough down on the handle bars, there would be enough distortion to notice, but it seems much too close to the bike to be useful at any of the slowest of speeds.

      2. Worse yet it could possibly create an artificially flat-looking surface that in fact has holes and shit.

    3. Perhaps mounted on a fork near the hub…

      Definitely easier to find dropped objects in poorly lit areas when you put a flashlight on the floor rather than hold it in your hand.

      1. A regular headlight mounted on the fork would identify bumps and holes in the road just fine. No need for a grid. I’ve found that driving a car on a bumpy dirt road is a lot easier at night, since the rocks stand out in the headlights.

      2. Once upon a time, a light mounting tab halfway down forks was fairly standard. At hub level is probably too low, though you can get replacements for QR nuts which act as light mounts. But just having the light mounted on the fork crown gives a marked advantage over a handlebar mounted light.

    4. When riding at night, a headlamp is useless for depth perception, since the shadows are too small. A light on the handlebars is very effective. 

  3. I like the idea, even if it has problems. Often riding in the evening or at night means that there’s plenty of light to see where you’re going with, but the pavement in front of you is completely impossible to see. 

    However, in those conditions you probably want a headlight and a tail light anyway, for visibility to cars. I think a set up similar to fog lights on a car (mounted low, aimed almost straight ahead along the pavement, super bright) would be helpful. But that wouldn’t be particularly sleek or cool :)

    1. “I like the idea, even if it has problems.”

      I like the idea of perfection, independent of whether it is achievable … a stunningly irrelevant comment, like yours.

  4. Neat idea, but projecting the grid 2 meters in front of the handlebars won’t give you much time to react!

    1. Two meters?  That’s not so hard.  I’ve bulls-eyed womp rats in my T-16 back home and they’re not much bigger than two meters.

  5. Another too-clever solution that cyclists don’t need. How about these guys just make a brighter bike light with some lateral projection for off-angle visibility, instead of this? I can see the bump in the road well enough and it isn’t going to affect me all that much, but I will be affected by that car pulling out of the side street right in front of me because he can’t see my little spot of light aimed at the road.

    1. It does clarify that we are pushing the Mercedes anti-collision cameras and drivers to react in 200ms or so in order to share a notion of what sort of gash opened in the earth, how wide the actual cyclist is (panniers et al,) and which shall opt to go airborne to vaporize the Skynet drone.

      I like that it deviated from monochromatic red, but it’s clear the next step where you point out the 8cm or 400m sinkhole and need to press triangle fast to start the minigame has been left out for insurance purposes. Nobody pedals near c; just use IR and ranged visible markers until you need to flash for 6ms at range where the pattern failed. Then the psychommu unit has to start regenerative braking until the Fiat blows across your path.

  6. I had an accident in a situation in which this device would have been perfect.  Crossed a highway from the right side to left in the dark, anticipating a left turn into my subdivision of that time.  Perhaps stupid, but traffic could be heavy and you had to take what you could get.  As I went along the gravel shoulder for a small distance before hitting the turn,  oncoming traffic blinded me. I could see everything but what was directly in front of me.   Unfortunately I drove into a deep meter long pothole and did a header onto my back. 

  7. Used in concert with other lights it looks interesting.  A headlamp puts light where you are looking, but makes depth vanish because there are no shadows visible to the viewer.  Mounted lower on the bike, the lighted grid would give depth to the surface.  I would like to try one before discounting it.

  8. All the grids shown are projected from directly above the ground.  The concept has the projector situated below the rider’s eyes (on the handlebars), which would, at best, produce an inverted effect absolutely unlike the images shown.  It would work if you attached a 20-foot long fishing pole to your helmet, and hung the projector off the end of the pole 20 or so feet in front of you.

    1. It’s clear that these folks have not thought this idea through, much less made a prototype of any sort.

      I can’t see why they received an award for such an incomplete project, unless the other entries were even more flawed.

      1. Guess you didn’t think this through to Keystone Correction.

        I can’t see why you posted this comment unless the one preceding it was worse.

      1. It’s not the shape of the grid that Graham Fyffe is talking about, we’re all aware of Keystone Correction. It’s the way the grid is distorted by the topological features of the area it’s projected onto. The effect is directly related to the position of the projector relative to the viewer’s eyes. The image above is of a grid projected onto the road from above, not from the handbars of the bike. A grid projected from below eye level would give an inverted distortion which could be dangerous. It certainly wouldn’t give the nice clean view that all the images show. These comp’d up images are very misleading.

        1. The purpose of keystone correction is to compensate for 3 dimensional angular displacement with the correction based on a theoretical flat plane; accordingly any disturbances of that plane will be seen as distortions, in this case distortions of the grid indicating obstacles.

          It is a very simple and common problem inherent in projection from a fixed point. 

          In any case of observing a projected light from a point with angular displacement from the observer’s vantage point there will be some distortion but humans learn to compensate for it just as we learn to invert images we actually see up-side down to right side up.

          Without actually having the engineering calculations or testing the system, your conclusion is speculative as to the value of these lights.

          But then, this is the internet so you must be right because, um, opinion.

          1. Have you considered the fact the angles of the light projection and the rider’s vantage point are different resulting in triangulation? Because, mathematics.

          2. Honestly, you’re not right about this.

            The point isn’t whether or not you can correct the grid to show you rectilinear lines on flat surfaces.

            The point is that if you project a grid from approximately the same angle as you are looking at it, you won’t see any distortion from bumps, because from your perspective you’re seeing the same grid that the light is projecting.

            Think of it this way: imagine the grid was projected straight down, and you were looking straight down. Would you see any distortions? No, you’d see a perfectly rectilinear grid, regardless of the shape of the ground.

            From an angle, the same principle actually applies.

            In the image below, the top image is what it would look like if you projected two circles into a room and were looking from the exact same angle as the circles. As you see, they look exactly circular, and tell you nothing about the shape of the room. If you looked at the projection from a very different angle, however, you would see the distortion, as the bottom image shows:


          3. Thanks for your sincere response. 

            If the light projector was mounted on the rider’s forehead projecting at approximately the same angle as the rider’s line of sight this might be a problem but I think the projector would be mounted lower on the bicycle’s headstock or handle bars resulting in triangulation, hence the ability to see distortion of the grid.Whether it is enough to make the concept useful we could determine by testing or, with sufficient data, modeling.

  9. The laser can dice squirrels, raccoons and other wildlife. Also, every time you ride through a puddle, the reflection causes passenger airliners to crash.

  10. Related, but for runners (and with an active kickstarter if much less groovy tech:

  11. Neat idea, although I think there is a simpler way to achieve the grid rather than depending on the optics suggested. 

    Why not just use a simple laser pointer and a HOE (Holographical Optical Element) It is a thin plastic film, when a laser beam passes through it can can produce a given pattern but does not need to be focused. These can be mass produced  extremely cheaply. need to wait for this to be designed and built, just order your HOE and a laserpointer and put it on your handlebars.

Comments are closed.