Having two camera systems on a motorcycle helmet, with one positioned behind your head and another beside it, can serve several purposes. While I'm not aware of any specific commercially available helmets with this exact setup, I can provide some possible reasons for such a configuration:
Increased situational awareness: A camera positioned behind your head can provide a rear-view perspective, allowing you to monitor the traffic behind you without having to turn your head. This can enhance your overall situational awareness and help you make informed decisions while riding.
Improved safety: The rear-facing camera can act as a supplemental rearview mirror, compensating for blind spots and providing a wider field of view. It can assist in detecting vehicles approaching from behind, minimizing the risk of collisions during lane changes or maneuvers.
Documentation and recording: The camera systems can serve as onboard dashcams, capturing your rides from different angles. This can be useful for documenting scenic routes, sharing experiences with others, or providing evidence in the event of accidents or disputes.
Vlogging or content creation: If you're a motorcycle vlogger or content creator, having multiple camera angles can add visual interest to your videos. You can switch between the two camera views to provide unique perspectives, capturing both the road ahead and the rider's reactions simultaneously.
Personal preference or experimentation: Some motorcyclists may choose to experiment with different camera placements to find the configuration that works best for their needs. Having two cameras, one behind and one beside, might be a personal choice based on individual preferences or intended use cases.
Ultimately, the reasons for having two camera systems on a motorcycle helmet, with specific placements, would depend on the preferences and objectives of the rider. It's important to ensure that any modifications or additions to a motorcycle helmet comply with local laws, regulations, and safety standards.