//
you're reading...
leJOS Features, Projects

EV3 LIDAR Sensor

lidarflash

I had planned that my next article would be part two of the series on line following (part one is here), however a new sensor from a company call PULSEDLIGHT (http://pulsedlight3d.com/) caught my attention. Basically this sensor (the LIDAR-Lite) provides a relatively low cost laser based range finder that provides centimetre resolution with a maximum distance of up to 40m and a sample rate of around 50Hz. The sensor uses an i2c interface and is relatively compact. It seemed to me that if I could make it talk to the EV3 and arrange some sort of  rotating mechanism then it could be used as the basis of a low cost LIDAR sensor.

sensor3

The actual sensor is shown above. I will post more details of the device in a follow up article. To get things working I’ve had to rework the leJOS low level i2c code and I built 3 versions of a rotating scanner before coming up with one I was happy with. But for now here is a video clip of some initial testing, this thing is very cool!

Advertisements

Discussion

4 thoughts on “EV3 LIDAR Sensor

  1. Nice job. That’s pretty impressive. I’m thinking of trying to get one working with ev3dev. Do you have details you can post of how you physically conected it to the ev3 sensor port?

    Posted by john lockwood | 2015/07/25, 19:46
    • The sensor is an i2c device. The tricky part is that it has built in 10K pull up resistors. This causes problems with the EV3 as the data line has a protection resistor in series with the pin. This in effect forms a potential divider with the pull up resistor when the EV3 tries to pull the data line down to zero volts and means that the sensor does not see a zero volt level. I worked around this by adding an extra pull down resistor of around 8K (I think), which enabled the logic zero to be detected but still allowed logic one to work. Ypu may need to experiment a bit to find a value that works for you. To get the device to work at high speed I reworked the leJOS i2c driver. I may write a further article about that at some point, but the weather is too good at the moment. I’m busy riding my bike rather than writing articles! If you want to discus this further please post on the leJOS forum as I think that is a better place for a discussion than here.

      Posted by gloomyandy | 2015/07/25, 21:32
  2. I would love to see more on this, the circuit and code? Are you ok to share this in the future?

    Posted by Simon Burfield | 2015/12/17, 12:37

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

About leJOS News

leJOS News keeps you up-to-date with leJOS. It features latest news, explains cool features, shows advanced techniques and highlights amazing projects. Be sure to subscribe to leJOS News and never miss an article again. Best of all, subscription is free!
Follow leJOS News on WordPress.com
%d bloggers like this: