Lidar with galvo mirrors

[danseidel]

Can I us X and Y galvo mirrors to steer the beam of a laser rangefinder to trace a specified path? Consider the LIDAR-Lite 3 for example. I imagine I could place a mirror in front of the emitter and reflect the beam over to the galvo mirrors. The galvo mirrors would steer the beam to trace a path. As long as the path is within the field of view of the receiver I think it would work. Does anyone know what the field of view is for the receiver? Are there any suggestions for a longer distance rangefinder I could use?
[h1][/h1]

[scharette]

Hi,

This may work, with the assumption the equipment used is reflective to the IR used by the sensor. We’ve contacted the manufacturer to obtain more details about this idea.

We will post here again once we have more information.

Sincerely,

[scharette]

Hi,

Here is a copy of the manufacturer’s response:

@manufacturer

]The transmit beam at ½ degree is relatively large when it exits the sensor. It is approximately the same size as the transmit lens. This means that the mirror needs to be placed close to the transmit optic and needs to be at least 13mm in diameter. As it diverges with distance it becomes even larger. The beam size beyond 1m can be calculated by using the formula Distance/100 = beam diameter at that distance in whatever units you measured the distance. So, unlike the common perception of a laser beam being a fine point of coherent light, in LLV3 it is more like a flashlight. This divergence is the result of the eye safety certification requirements for this product. It can be scanned at distances out to approximately 10 or 15 meters with adequate resolution, but it isn’t going to have the same resolution as devices that are specifically designed for scanning applications which have more coherent sources./:m]

]The receiver FOV is approximately 10 degrees. Even with that large of a FOV, the total amount of area that could be scanned is going to be limited and because of the beam divergence at distance, the resolution of the scan may not be as high as they require./:m]

]Unless the mirror is of high optical quality, there may be scattering of the light as it is reflected off the mirror that could leak into the receiver and produce false readings. The LIDAR-Lite technology transmits and receives at the same time, so in applications where there are reflective surfaces close to the optics, crosstalk is always a possibility. The other consideration is that the scattering of light as it is reflected off the mirror will also reduce the amount of energy available at the target and this will reduce the effective range of the system./:m]

With all of this being said, there are some other things worth mentioning:

@manufacturer

[highlight=#ffffff][font=arial, sans-serif]Now that we’ve stated some of the challenges, we would still encourage this user to experiment with this concept. Even with the limitations, there are some valid reasons that a scanning system like this could be useful in robotics. Also, an electronically scanned system is going to be less mechanically complex and, therefore, more reliable and less costly. It will also have the advantage of reduced size, weight and power consumption.[/font][/highlight]

We hope this helps!

Sincerely,

[marcusbehrens]

So danseidel, have you experimented with this concept? I would like to use the rearward facing part of the 360 scanning circle and use 2 mirrors to project it at another angle to the front to have a second scanning half-circle scanning at a different level for free. This way the mirror could have a fixed position and it would not have to turn.

I guess you have been attempting to use a galvo to not just create one scanning level/circle but multiple.