Joined: 30 Sep 2006
Posts: 673
Location: Perth, Western Australia
The spektrums trainer input/output is just an align pulse, then the 6 servo signals of varying pulse widths _________________ They say that he crossed the fine line, from insanity to genius.
So apparently it spits out data on the trainer port and the format has been documented. However I am yet to see it being used in the actual trainer mode, I only made it 15 pages through the RC groups thread of 200+.
The easiest option might just be to generate a ppm signal and feed that straight in to the transmitter module and loose the whole radio section. _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
Got OpenCV working and had a bit of a play lastnight. Abandoned trying to get it to work on mac and moved to Ubuntu its in the package mannager so that makes install very easy.
At the moment I am trying to segment out a green and blue square on a brown background. So far I have failed. There is many tutorials around on the internet so bit more learning to do yet. Also the brown tiled floor is pretty shiny. I get the feeling it would be a lot easier on a black background. My mate has some blackboard painted MDF hanging around from techfest comp so may go pick some of that up when I get a chance and see how that goes. _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
I got PPM wire hanging out of my Hobbying 6CH radio. I intend to drive it straight off a micro with voltage divider. Input from logic on radio board is using a 20K divider I am using a 1K divider so hopefully that should basically override any signals from the onboard electronics. I don't have a oscilloscope so debugging what the hell I am doing is proving a little hard. Will give it a bit more of a try in a week or two when uni is open again.
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
USB 'Scopes are cheap these days if you're playing with Micro's a bit.
I got the USBee Sx model www.usebee.com - about $150 I think - its a logic/protocol analyzer as well, but there are heaps of others out there these days. I think you can program custom protocol decoders into the software, so you could automatically decode the PPM signal into values. _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Sun Apr 04, 2010 10:25 pm
seanet1310
Joined: 08 Nov 2006
Posts: 1265
Location: Adelaide
nice i can see plenty of uses for the protocols like i2c, spi and ps/2. Too bad the lack of analog in the cheaper models like SX _________________ Remember to trust me, I am an Engineer.
This is what I am thinking, bit more flexible than logic analyser. Modules look good though _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
So anyway, hooked up scope to TXs PPM signal to a scope today. Basically it looks like a normally high signal with 7 low start stop signals about 0.6ms long and 6 high pulses in between them of 0.5ms - 1.5ms long which is the servo signals.
I have managed to replicate it on my little chip, just basically hard coding in the servo speeds. Atm working on a way where you just send serial data to the port to tell the chip what speed to make which servo output.
Anyway back to uni work now. Might have another go at it tonight. _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
Ok so I got a bit of work done on the TX interface. It works though is still not really done properly. It is a terribly hacky code which fails 50% of the time but the basic principle is there. To change the speed you send #1&150 where number following # is the channel and number following & is ppm value.
Had a bit more of a look at it. Seems as though it should almost be plug n play. Though support for a non-firewire camera could be an fairly big issue.
If you forwarded the right port then you could even broadcast the results over the internet. You might even be able to SSH straight to the serial stream. And write to the microcontroller for the robot control. If ping is ok you could have remote combat even if it is just RC controlled. _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
Hmmm. Vision stuff only works atm with a high end firewire camera atm, bout few thousand from what I have found prolly cheaper but that really rules out anyone from doing stuff themselves. They are working on v4l (video for linux) plugin but that is a while off by the looks.
Wiimote is another option. Put IR beacon on the robots and use it to track it them. Few problems is height above robot you need to track them and which robot is which.
One option is that we could make a little driver using a servo board and then poll the position of each robot. If we get to bigger scale could always just put the sensor on the robot.
Wiimotes are around $75 which is much cheaper than a high end firewire camera. _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
Mon Jun 07, 2010 7:00 pm
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
why does the camera need to be "high end"
firewire is pretty common on most cameras, its fading a bit now with usb becoming more prevalent, but most any digital tape based camera will likley have a firewire port on it. _________________ Mechanical engineers build weapons, civil engineers build targets
Yeh was my first though as well the software is designed to work with scientific cameras. I don't have access to any firewire video cameras but from what I found looking around the internet the protocol for the DV cameras is different again to the scientific ones.
Not 100% on this but what would more people have access to a wiimote and bluetooth or a computer with a firewire connection and a DV camera? _________________ Steven Martin
Twisted Constructions
http://www.botbitz.com
Tue Jun 08, 2010 10:39 am
Valen Experienced Roboteer
Joined: 07 Jul 2004
Posts: 4436
Location: Sydney
bt + wii would be cheaper to aquire.
that vision mob say they will support V4L in the future, so any webcam should suffice at that point.
why not just feed the output of a decent webcam via broadcast to all teams? _________________ Mechanical engineers build weapons, civil engineers build targets
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum