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Ultra Sonic and RGB Sensor


#1

Hi I need to make a device that can detect colors and Distance and Obstacle finder. How can I do that , Still I couldn’t find proper modules for this purpose Please Help me :slight_smile:


#2

If you know electronics, you can use the extender module to add the sensors you need. Otherwise, you need to wait till someone offers these modules. GHI is working on many for near future.


#3

Hello Gus,

is it possible for you to drop a hint on what’s next in gadgeteer-line from GHI? I’d love to know what you’re working on right this very instant. Is there a list I perchance missed…?

/Morten


#4

It is unusual for companies to tell you what they are working on :slight_smile:

But I can share this, there is over 50 more modules to come this year.


#5

So we can expect five per month…


#6

Sure, 5 a month :slight_smile:


#7

It sounds like you may be playing with the sort if ideas I am.

Here are a few bits I have noticed which may help, and a few observations.

If you are after obstacle avoidance, then you are probably mounting this on a robot platform.
Each motor driver runs two motors and takes up one of the two P slots.

If you want to connect a servo to move the camera, or activate a grabber, then that is your other P slot gone. The P slots are as far as I can tell the only slots that support PWM devices.

Colours and distance are more my sort of thing.
Without knowing the constraints of the system you want to build, can only offer generic advice.

A lot depends on the environment you are working in. If indoors I would preferably go with an IR beam, if outdoors then I would go with a sonar device.

IR does not work well in sunlight. Sonar can get very confused in a noisy environment.

As for colour, it depends on how much the colour of the item you are after is different from the background, and how the lighting is. If you also have images of the background without the item, that is also handy.

Line following is easy, as just point down and forward, and big coloured object that contrasts with floor.

Our brain does a lot of interpreting of what we see. Take a picture with the camera you aim to use with the items you are interested in at the max distance you think you will be working at, and in the lighting conditions you will want the project to work.

Place the images into a paint program, then move your mouse over pixels and boundaries and look at the RGB values. If you are not in a good light, you may be surprised how subtle and varied colours are. Put a piece of white paper in the image somewhere then look at your colours again, you will see that they have changed quite a bit. Most cameras have an auto white balance built in, this is a pain for computer vision. You can get round it, just easier if it was not there.

If you can make the items you are interested in vastly different from the background, then life is much simpler.

Also once you have found the items in the image, you can lock on to them, as you know where you expect to find them in each image, and can then adjust your course to correct any drifting.

From just a simple flat image to calculate distance, you would normally do one of the below:

-Use a device like the kinect which gives you distances and colour.There is too much data from this to use with a gadgeteer (or any electronics projects that I know of short of linking it to a laptop).

-Sending an IR beam slowly and smoothly across the field of view. Calibration is a pain here, but you can get a nice map for a single slice of the image.

-Knowing the exact size of your object. By knowing its size and how large it is in the image you can roughly calculate the distance.

-Being able to exactly line up your sonar/IR with the object. i.e. if the object is exactly in the center of the image, and the sonar device is pointing at it, then volla.

-Or having reference points in your image,

Have not had much time recently, but my aim was to be able to say ‘Find Zoiberg and the device would go off, not connected to the computer, find the Zoiberg toy, and either grab it, or run it over.

I picked up:
A compass module to work out which way I am facing. Very impressed by this.

Two sonar devices (not sure if they will confuse each other) but have linked them both to an extender.

A Bluetooth module, as could not get peer to peer to work to my mobile phone. May have been able to write this given time, but wanted a quicker solution.

Two motor controllers. To make it move.

Had problems with the camera module for a long time, and became frustrated. The camera module works great now with the latest release, but decided to use the voice recognition, gyro, and camera on my phone then communicate via Bluetooth back to the device.

No idea of the name for them, but after four bumper/feelers. Worried about the device getting caught on a corner and the motors burning out. A couply of those infront of the wheels or tracks, then will know to reverse if it hits anything. I have seen platforms with white and black disks on the inside of the wheels, where you get sent back a signal on how fast the wheels are spinning, could probably use that to see when have hit an object.

Like the idea of being able to hold the camera in my hand and the device goes off after the target, or being able to put it on the device, and it turning to first person mode.

Hope some of this has helped. Sorry if you already knew this.

Regards,
Jonathan.


#8

We always benefit from any additional feedback. Thank you.

GHI tries its best to make the modules generic so they are used in many application. We let you make the decision on how you like to use a module, or a mainboard for that matter.

About servos and not having enough P sockets, you will love the module we are planing for, which is not P type :slight_smile: After all, we are also users of these modules so we do see them from the end user point of view.


#9

50 Modules!!! Gus can I just give you my credit card now and have you ship them to me as they released?

Oh by the way can we have a mainboard with way more sockets?


#10

Yes sir…almost done!


#11

@ Gus that sounds great - I look much forward to the a@ Gus that sounds great - I look much forward to the announcements! Good stuff!

@ Jonathan that was right helpful to me as well - great info, thanks a lot!


#12

Gus,

Any chance we’re looking at a Cerberus+ type board with the Cerberus-type CPU paired with external flash and RAM?

Possibly in a module a la EMX or ChipworkX?

Be careful what you say, they may tie you to a chair and not let you out until it’s ready :wink:


#13

From your point if view, why not just use emx or hydra?