GB2490889A - Light projecting safety device for a bicycle - Google Patents

Abstract

A device b that attaches to a bicycle a (or other two-wheeled vehicle) and uses light to project an image c down onto the road surface, 5-12 metres ahead of the bicycle. The projected image is designed to alert other road users to the cyclist's presence, especially when projected from a bicycle in a hidden position, for example from within a large vehicle's "blind spot".

Description

United Kingdom Patent Application Light Projection Safety Device for a Two Wheeled Vehicle Inventor: Emily Brooke

Description

Background

79% of cycling accidents in the UK occur when the bicycle is going straight ahead and a vehicle manoeuvres into them [Ref. 1]. By far the most common Contributory Factor' recorded by the police at an accident involving a cyclist is, "Failed to Look Properly", on the part of the driver. It is one of a possible 77 Contributory Factors and it is cited in 58% of cases. All the evidence shows that the bicycle is just not seen on urban streets, or if it is, it is too late. Ultimately, even when lit up correctly with lights and reflective clothing, a cyclist in a bus' blind-spot, is still invisible. This is the most common cause of accidents; a bicycle travelling up the inside of a vehicle unseen, with the vehicle turning left across its path, crushing the bicycle (see Figure 1).

This is more often the case in cities (with 75% of cyclist accidents occurring on city streets) and with large vehicles such as buses and HGVs with large blind-spots. Another extremely common accident is a vehicle pulling out of a side turning into the path of an unseen cyclist. The majority, 64%, of cycling accidents occur within 20m of a junction. These are the problems the invention is trying to solve. The innovation is aimed to increase the visibility, communication and ultimately the awareness of the bicycle on urban streets. Make it seen, and seen in time. Tackling the famous cycling accident nicknamed SMIDSY'-Sorry Mate I Didn't See You!' [Statistics above from Reported Road Casualties Great Britain: 2009', Published in September 2010 by Department for Transport].

Statement of Invention

The invention and subject of this patent is a small, mobile device that attaches to the handlebars of a bicycle or any two-wheeled vehicle, that uses high intensity light to project an image down onto the road surface, in front of the vehicle, alerting other road users of its presence.

Advantages The most common, similar device to the innovation on the market, is your typical bicycle light. It is the law in the UK for a bicycle to have rear and forward-facing light, red and white lights respectively after dark. They can be flashing, but no faster than 4 Hz, to protect photosensitive epileptic suffers. Bike lights do significantly improve the visibility of a cyclist, but only if you can see the lights themselves. Standard lights provide very little illumination to the environment around them, and unless the actual source is in your eye-line, they are hard to detect. This is not the case for the innovation and subject of this patent, as it increases the cyclists' footprint with a projection, and allows it to be detected before you even see the bicycle itself.

The other problem with bicycle lights is that in dark, or near-dark conditions, it is extremely hard to distinguish the speed at which the cyclist is travelling, or even their distance away and exact positioning, from just a point light source. However, the motion of the projected graphic along the ground of the innovation will communicate the speed of the cyclist and direction they are travelling. I will also potentially include arrows into the projected graphic depicting its direction of travel (see Figure 7). A possible future consideration for this product, is to integrate a front-facing regular bicycle light into its design.

Related products to the standard rear and forward-facing lights, are additional, moveable lights, that can be attached to other parts of the bicycle, the rider's clothing or helmet. There are also other innovative illumination devices for cyclists, such as bicycle spokes that are illuminated with strips of LEDs, integrated illumination in clothing, such as jackets with electroluminescent wires and reflective materials etc. But ultimately, all of these products do not solve the problem the innovation sets out to try and solve; -you can be lit with all of these products, but the same rule applies that if the cyclist is in a blind-spot, it is still invisible! You cannot see the bike until you can see the illumination source themselves.

The only other product that I have found that also creates a projection for the cyclist, and increases their footprint on the road, is a product that is still in the concept phase in America, and called Light Lane'. It uses a green DPSS Laser to project two parallel, straight lines, down onto the road behind the bicycle. This creates the effect of a virtual bike lane travelling along behind the cyclist It informs traffic approaching the cyclist from the rear of a safe distance in which to pass the bicycle. Although it proves the technology works in this application, it does not tackle the problem the innovation solves; it does not in general increase the visibility and communication of the bicycle to all other road users. It does not warn traffic ahead of it of its presence, it does not increase the cyclist's awareness at the most common causes of accidents (left turns and vehicles pulling out into the bike's path) and it does not project out from a bus' blind spot alerting, the driver of it presence.

Drawings An example of the invention will now be described by referring to the accompanying drawings: Figure 1. Shows the most common cause of cyclist accidents. The bicycle is travelling straight ahead (a) and is in the bus' (d) blind-spot. The bus is turning left, shown by the indicator (e), and collides with the cyclist.

Figure 2. Shows the second most common accident, a vehicle pulling out of a side junction into a cyclist's path, depicted by arrow (n), as well as the previously mentioned most common accident, a vehicle turning left, shown by arrow (1). Both of these situations are exaggerated when there is a cycle lane along the left side of the road (g), where the cyclist feels confident to ride with their right of way, although vehicles still manoeuvre into their path.

Figure 3. Shows the overall concept: A bicycle or two-wheeled vehicle (a) having a device (b) that projects light down onto the road surface ahead of it, creating a projected image (c).

Figure 4. Shows one variety; a laser module (h), shining a beam of light through a diffractive optical element, which produces a projected image (c).

Figure 5. Shows a variety of internal circuitry of the device, with a battery (j), switch, (k), light source (h), and a circuit board to create the optional flashing of the light source.

Figure 6. Shows the concept working from the view of the rider. (a) Depicting the bicycle, (b) the projecting device and (c) the image down on the road surface ahead of the cyclist.

Figure 7. Shows a possible projected graphic with a simple, recognisable bicycle symbol and arrows communicating the direction the cyclist is travelling.

Figure 8. Shows a possible projected graphic with a simple, recognisable bicycle symbol held within a triangle, which indicates the direction the cyclist is travelling and also a warning with the triangular frame.

Detailed Description

The most likely arrangement of this innovation comprises a light source of a laser module, of relatively high power. One variety is 100mW, but this could be decreased to approximately 50mW. This high intensity beam is modified through a diffractive optical element (shown (i) in Figure 4), to create the desired image. This also disperses the intensity of the coherent beam, reducing the safety risks to an appropriate level. The diffractive optical element shapes the coherent beam of light, using constructive and deconstructive interference created through diffraction to create an image. This variety comprises the laser source being a DPPS solid state, green, laser of wavelength 532 nm. This is because the human eye is most sensitive to wavelengths of light close to this wavelength.

The power for this variety is simply two changeable, 3V (AA) batteries, although other varieties include the option for the device to be rechargeable by USB port or to use rechargeable batteries.

There will be a removable section to the casing for the batteries to be changed easily.

Access to the laser module is restricted such that by taking the device apart, it renders it unusable, so that the laser cannot be used independently of the complete device and therefore when not shone through the diffractive optical element.

In one variety there is also the option for the device to be removable from its fixture to the bicycle. In one variety the laser is automatically disabled when not sitting in its fixture, so the laser cannot be shone independently of the bicycle.

A further variety also includes the feature of the laser being equipped with a position sensor, such that if the bike is not vertical, the laser is disabled; preventing it working in the case of the cyclist falling off the bicycle and the device shining up towards people's eye-line.

One variety allows the laser to rotate around the axis of the handlebars and allows the distance of projection to be adjusted. It is most likely to be between Sm and 12m, but it could also be altered to be closer or further.

The graphic projected is most likely to be a recognisable symbol of a bicycle, with arrows depicting the direction the bicycle is travelling (Figure 7) or another version has a recognisable bicycle symbol held within a triangle, which indicates the direction the cyclist is travelling and also a warning with the triangular frame (Figure 8).

One variety includes a small circuit board (I of figure 5) that provides the option of a flashing image, most likely 3 to 4 Hz, as this maximises attention and perception and saves battery power but is low enough to prevent a risk to photosensitive epileptic sufferers.

One variety comprises the casing to be made of silicon rubber, making it tactile and flexible, and protected if dropped. This variety is also waterproof.

It is most likely there will be a button on the back of the device, closest to the rider for easy access. The button will be held down for on, and stay on, hold down for off, and stay off. One variety also includes an additional control of a second press once on, activates the flashing option and again to deactivate.

A further variety allows the device to be attached to the rear seat post and project an image behind the bicycle in a similar way.

Claims (6)

1. Claims 1. A device for a two wheeled vehicle that uses light to project an image down onto the road surface, alerting other road users of its presence, as seen in Figure 3.amendments to the claims have been filed as follows 1. A device for a two-wheeled vehicle, the4evice comprising a fixture for attachment to the two-wheeled vehicle, the device being arranged to use light to project an image down onto the road surface, a distance of between S and 12 m in front of the vehicle, alerting other road users to its presence.
2. 2. The device according to claim 1. further comprising the projected image to be at an adjustable distance ahead of the bicycle.
3. 3. The device according to claim 1, further comprising the projected image to be a recognisable symbol of a cyclist
4. 4. The device according to claim 1, further comprising the device to be attachable to the handlebars of a two-wheeled vehicle.
5. 5. The device according to claim 1, further comprising the device to be removable from its fixture to the vehicle.
6. 6. The device according to claim 1, further comprising the integration of a front-facing, regular, bicycle light into its design. 0** . .. * *0*S! *0 * * * . * a.. 0*sI n * A * * *. a*It)4SS * A