Slashdot Mirror
Homemade Heads Up Display For Bicycling?
An anonymous reader asks: "I am a geek that bicycles in an urban center. After seeing this commercial product, I was interested in the possibility of building a homebrew HUD for a bicycle helmet. I searched the usual places and couldn't find much so I thought I'd ask the readers of Slashdot. A HUD that displays speed, distance, and cadence seems very feasible as many bike computers collect that data. A great longshot would be a range-finder that told you the distance to the object you were turned toward, but I'm not crossing my fingers for that. So what components would be needed to make such a cool device?"
A cheap, easy way to do it would be to go the 'ambient device' route and use a small number of coloured surface-mount LEDs (perhaps placed along the inside edges of your glasses) and train yourself to recognise what they mean when lit up in certain combinations.
It would be a bit safer than a textual display which requires you to change your eye's focal distance to read. Just make sure you don't blind yourself with it at night.
Uh, I don't know what you read into the question, but no sort of laser device is required. The best solution would be a tiny helmet-mounted LCD that could be glanced up at, or a prismatic system to overlay the display onto their view of the world. A laser or ultrasound rangefinder is useless without an optical sight, but one could easily be built into the display, in a manner similar to red-dot sights on firearms.
The idea that a hud compromises situational awareness is somewhat naive. Yes, a poorly-designed system could compromise SA, but a properly thought out HUD system will have no effect on the user's ability to control a vehicle. Frequently, HUD systems vastly improve a user's abilities - modern fighter jets are unflyable without their HUDs. People are working on wearable computers as a way of improving the user's perception, like eyetap.
Virtually all civillian head-mounted-displays weight less than 50g, and therefore crush like a butterfly under heavy impact. I greatly doubt that a tiny LCD would compromise a helmet, and if it does, then why bother with a helmet? If it can't stand up to a tiny piece of plastic shrapnel, what chance does it stand of keeping your brains safe from hurtling steel?
This is my, umm, naughty dream high tech bike helmet. It doesn't exist yet. Basically this would be a fancy new-school helmet like a Giro Pneumo, with microelectronics that create a short range phased-array radar. Inside the helmet is a grid of small air bladders. As you move through the city, the radar generates a crude map which is translated as pressure around your skull. You feel a constant roll on the right side, parked cars. Behind and to the left, the moving press of a car passing. Alternately, the radar hardware could be mounted on the bike. Hand/Eye free computing (tactile) holds a lot of potential for custom uses.
On topic, I'd recommend at most getting a decent Cats Eye cyclocomputer, maybe a GPS to go with. As someone who rides almost every day, please take this advice: when riding, just ride. Like the urban rider above, that fraction of a second is all-important. Displays, gadgets, heck even waterbottles are distractions. Work on improving your hearing instead, developing your brain and senses.
Stay safe on the road,
Josh
gigantino.tv - Heavy but weighs nothing.