Raspberry Pi Forums

badook

In my project I chose sqllite as database, because this way I don't have to have a DB server running. The python code which manages the DB is this one . The server running on the raspberry is this file . Beware that security measures are pretty much absent at the moment. When the app on the smartpho...

badook

I've been struggling to get decent processing speeds for my project. Running some OpenCV filters is quite slow on the 700mhz cpu, and with your work it seems like my lil' robot might finally recognize obstacles a lot faster. I'll definitely try it...Keep up the good work! Edit: Any chance of a Pytho...

badook

I think you need a capacitive touch sensor. Sparkfun sells one based on MPR121 for $9.95. A cheaper alternative would be one based on MPR121 , I think it uses the I2C protocol but I'm not 100% sure it can be used wit the Raspberry PI. EDIT: I just read that you need a wireless one. My best guess wou...

badook

The android application is developed in Java using Eclipse. To receive messages it uses Google's GCM.
If you're interested in the source code send me a pm

badook

pi@Home Hi, this is a project I've worked on for some time. It consists of a raspberry pi connected to several sensors + wifi internet, which alerts me on my Android phone of several events. The reasons I decided to start this project are: - I wanted to learn a little of electronics, the practical ...

badook

Very interesting, I'd love to make a project like this too, if only I had the time. May I recomend buying the MPU on ebay? $4,32 : (x1) : http://www.ebay.it/itm/MPU-6050-3-Axis-Accelerometer-3-Axis-Gyro-module-3-3V-5V-For-Arduino-/171046300701?pt=LH_DefaultDomain_0&hash=item27d3276c1d&_uhb=1 They ar...

badook

Thank you for your help.
I have already worked with optocouplers, so that's what popped up in my mind. Now I'll document myself about SPDT relays.

Thanks!

badook

Hi, I'm trying to interface my existing alarm system to the raspberry. In my alarm system there are several PIR sensors which are normally closed. So if there is no movement keep the circuit closed. I'd like to manually trigger one of these PIR when some event happen. I had thought to use an optocou...

badook

Actually, if there are many wifi networks in range, you could fingerprint the wifi levels in room and get better precision. This means that you'd need to create a map of wifi networks strength in the room and then check whether a user is "near" to one of the memorized points. The advantage is that i...

badook

Depending on what kind of object you are trying to recognize there are several algorithms and implemented solutions available on-line. - One example is a tennis ball: http://wiki.elphel.com/index.php?title=OpenCV_Tennis_balls_recognizing_tutorial (this code is C, but you can translate it in python b...

badook

Thanks! I'll start experimenting right away!

EDIT:
Here it is, working like a charm! Next step: accelerometer+gyro+magnetometer

Thanks again

badook

nice work btidey! For mproved performance and lower cpu usage you could use the library RPIO ( https://github.com/metachris/RPIO ), which features interrupts on input gpios with very little cpu usage and fast response. Also, I just received three ultrasonic sensors, and I was wondering how to connec...

badook

Thank you for the extensive and detailed explanation. It was really helpful. I think that now I have a better understanding of what has to be done. I have just other two questions, I promise! If instead of a single diode I were to place 4 as a bridge rectifier, can the resistors be the same? Lastly,...

badook

Ok, I've documented myself about diodes and optocouplers. Do you think that the optocoupler 4N33 would be fine? Also, did you mean 0.5 Ohm and 1 Ohm resistors? Finally apart from connecting the gpio and ground from the raspberry pi to the optocoupler, will I have to use a pulldown resistor? Thanks a...

badook

Ok

...I'm still pretty new to the electronics world, I thought it would be simpler, but I'll look into it.
Thanks!

badook

Hi, I bought a model A because of it's low power usage, and now I'd love to put it to work. My idea is to have it near the apartment door and connect it to the doorbell, so that when it rings the raspberry notifies me on my phone. I've found several similar projects but all of them either use a wire...

badook

I agree, but the problem is not the raspberry pi model A, it's a linux problem with the realtek driver for this dongle (quick search: http://google.com/search?hl=en&q=rt2x00usb_vendor_request ). The simplest solution is use another dongle. As for why this only happens with the model A or why the hub...

badook

Hi jrmedd, after some testing I found out that using a usb hub (not powered) with the model A the problem seems to solve, at least for a few hours. I left it on for about four hours and the connection held up. Instead if I connect the wifi dongle directly to the model A after usually 5-10 minutes it...

badook

Well, since usb uses 5V, and Watts = Amps x Volts, the webcam draws 0.3A. Assuming you have a rev2 board, looking on the internet, it says that for devices which use 250mA there are no problems, except that if hotplugged it may make the rPI reboot because of a voltage drop. 0.3 should be ok, but I'd...

badook

This is very useful indeed. I only wish it was fully open source, because it would be more in line with the linux and raspberry pi philosophy ;) For those who prefer open source and/or are familiar with servoblaster, there is another project called pi-blaster specifically for dc motors which also us...

badook

I flashed another sdcard with Arch, and the same issue happens....sigh...I think the board is defective.

badook

hey sdjf, do you mean CTRL-ALT-DEL over ssh or with an attached keyboard? The part of everything.log relative to the last boot is the following: http://pastebin.com/sYBbAHrQ (Yes, the last line is truncated in the log). What's curious is that the last line was written at 16:37:42 and is truncated as...

badook

I set up the os on the sd card about a month ago, but it's fully updated. I'll reinstall archlinux on another sd card and try again...but I'm afraid it's a board defect. The reported temperature never goes over 33° but it just stops working...sigh.

badook

Hi, I recently bought a model A raspberry, because of it's lower power usage. The first thing I did when it arrived was to take the sd-card from my model B rev2 (with arch loaded) and I plugged it in the model A. At first everything worked flawlessly, it booted and I logged in through ssh without pr...

badook

I'm very interested in integrating the HMC5883L magnetometer too!

Search found 43 matches

Re: pi@Home: doorbell, intercom and more, notified on my and

Re: GPU Accelerated Processing Of The Camera Feed

Re: Wireless touch sensor to send SMS text message

Re: pi@Home: doorbell, intercom and more, notified on my and

pi@Home: doorbell, intercom and more, notified on my android

Re: [WIP] Quadrotor Project

Re: Normally closed optocoupler/relay

Normally closed optocoupler/relay

Re: Indoor location sensing

Re: using python with opencv

Re: Maxbotix Ultrasonic Rangefinder - LV-EZ1

Re: Maxbotix Ultrasonic Rangefinder - LV-EZ1

Re: Raspberry pi and 12/24V doorbell

Re: Raspberry pi and 12/24V doorbell

Re: Raspberry pi and 12/24V doorbell

Raspberry pi and 12/24V doorbell

Re: Model A STILL crashing intermittently

Re: Model A STILL crashing intermittently

Re: Will Minoru 3D Webcam work?

Re: PWM for servos, motors, and LEDs plus.

Re: Model A and B interchangeable SD card

Re: Model A and B interchangeable SD card

Re: Model A and B interchangeable SD card

Model A and B interchangeable SD card

Re: Yet more MPU6050 demo code