Can’t wait to get my hands on this
Can servo driver inside point laser in direction of flight?
there is cheap and there is expensive…what is the secret of Dynamixel actuators?
http://learn.trossenrobotics.com/projects/156-lidar-light-mapping-with-dynamixel-servos.html
@Emin_Bu - Yes, the servo can be controlled to point the laser in the direction of flight but you have to tell the LW20 which way to aim using data from the flight controller. This is similar to steerable headlights that you get on many cars these days.
There are cheap servos and expensive servos, with Dynamixel falling squarely into the second category. While the specifications of the Dynamixel servos look very good, the real question is, how well will the servo will perform as a component in a LiDAR? Both the cheap and expensive servos have limitations and I will be presenting a lot more information about this in the future.
The LW20 with an inexpensive servo will make a high performance, light weight sensor for obstacle detection and collision avoidance. How far we can push the technology in the future remains to be seen ;).
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Have you got any details on the ports and power. For example what supply voltage and i2C pullup voltage. What UART signal voltage. What supply current?
@skyscraper - at this moment:
Serial port - 3.3V and 5V tolerant
I2C - 3.3V
Power supply - 5V @ 100mA nominal (excluding servo)
Seems a good idea to link this here
http://discuss.ardupilot.org/t/mini-laser-module-interface-question/11697/40?u=skyscraper
This is something that I’ve agonized over for ages. In the end we selected the PCA9509 buffer for the I2C to improve the performance. We didn’t want to use hardware with a different physical protocol, such a differential signaling, otherwise there would be compatibility issues with the host systems.
I was thinking to putting this inside a cable, so it is converted to traditional I2C at each end of the cable, so you can use existing board connectors and existing hardware. The only thing to be aware of is to try to cater for up to 1 MHz I2C clock rates, if possible
To isolate the output I am currently planning to use a simple dual 74HC66 SPST analog switch. I cant see much advantage to the dedicated I2C buffers and they all seem to come with warnings about a raised Vout low voltage due to the mechanism used to detect data direction, which may cause issues with the above differential I2c IC.
EDIT Strike that it looks like you arunning at a lower voltage ! (In your case though maybe no buffer is necessary?)
I like the cable idea using the differential I2C standard - it could be really useful.
The PCA9509 buffer in the LW20 is serving several purposes. It has better drive capability for higher capacitance so it should work better on a longer cable. It also provides static discharge protection and improved noise immunity. Additionally, the LW20 can disconnect itself from the I2C bus which could be used to provide isolation in the event of a fault condition. And of course it allows the LW20 to use different internal voltages :).
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LW20 is Supermen of Lidars it seems…
Maybe Ant-Man 
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Hello Laser_Developer,
I´m quite excited about your new LW 20.
Can you confirm, that the device is usable plug´n´play with the latest Arducopter AC 3.4?
Did you get feedback from the developers?
Thank you in advance!
Ulrich
@Lubive - thanks for the question Ulrich. We have included a “legacy” command set in the LW20 so that it will be immediately compatible with existing AC and AP versions. However, these don’t have the scanning capability, only the laser altimeter. I hope we’ll be able to offer the full Ardupilot functionality soon but there is still lots of work to do before we reach that point. The good news is that the LW20 does have all the features built in and I’ll post more information as we move forwards.
@Laser_Developer To clarify, plugging the lW20 into the Pixhawk today will only give which altimeter reading? The longest or shortest (surface or ground)?
Hopefully the shortest.
@cndnflyr - The default is to provide the shortest result as Rob says 
. This is for safety reasons although in most circumstances when the target surface starts to get closer, the shortest and longest readings are usually the same.
From your web store, it looks like you can choose either IC2 or Serial. Since it’s a sealed enclosure, I’m assuming you can’t switch after the fact?
Are these cables pre-terminated with some connector? How long is the cable?
Thanks! Looks like a great product!
@jprouty: It is possible to change the comms format after purchase the LW20 by opening the unit and moving the wires to a different position on the internal connector. Similarly, damaged wires can be replaced or longer wires can be added if needed. The plug and wire part numbers will be in the manual along with instructions on how to make changes. All waterproofing seals are neoprene rubber so the unit can be open and closed numerous times.
The standard wire length is 35 cm and it is unterminated so that you can add whichever connector you prefer. The wire is shielded and the shield is internally connected to the Aluminum housing to reduce the effects of EMI.
Here’s a picture showing the cable gland at the back of the LW20. In this case the unit is driving a servo directly and it’s mounted on a small test stand. The cable is a special flexible type like the ones used in printers so that it can withstand millions of flexing cycles.
