Everything related to this one is hosted on Github links below.
LINKS to gihub:
Update - 20.05.2014: SD Card Image
Note: This image is configured with the bare minimum and for specific hardware
I'm using an UVC compatible webcam (logitech C110) and an Edimax wifi dongle based on RTL8188CUS chipset supported by the rtl8192cu kernel driver. Unless meeting the specs NOTHING else will work as is!
So here it is the software!
To get it working in your own wifi network you need to:
- download image from above drive
- get empty SD card - 2Gb minimum image is 2Gb in size
- flash image to it - now this depends on your OS on linux I do:
dd if=alpha.img of=/dev/xxx
where /dev/xxx is the SD card
- I will not post or support windows ... sorry
- once image is flashed you need to mount the SD card partition 2 and edit /etc/wpa_supplicant.conf to match your network by changing the defined network entry in the file ... SSID and PSK pass. SSID == ypur network name. PASS ... well simplest is to run wpa_password on you favorite Linux distro or use this to get the encripted string http://www.wireshark.org/tools/wpa-psk.html
- once done save unmount the SD ... insert to Pi and boot
- check router for IP assigned
Now if everything goes well you should be able to SSH into it with user root no pass ... if not you need to use the serial console.. sorry :)
You should be able to use Chrome to open http://your_lan_ip:8888 and get to the web interface.
Regarding hardware connections I'm using GPIO's 7,8 for the track servos and 24 for the webcam servo.
Warning! Do Not Attempt To Power Servos From the 5V pin of the PI you will KILL it!
Disclaimer: I do not care if your house burns down, your dog hates you, you cause an earthquake or anything else! This is offered as is. No support is offered ... unless you pay :)
Update - 15.05.2014 - We're Rolling Baby!
- created the top side + camera mount
- added a third servo to tilt camera
- changed the web interface to accomodate the web cam tilt
Working! Tested by Frits, Gareth, Bdk, Enigmerald, Badji, Jinx and others (sorry forgot who else :D )
Need to fix some issues with tilt code ... will push latest to github when done.
- fix tilt code
- redo track tensioners (never really happy with them)
- various tweaks to track design
- various tweaks to casing
Update - 16.04.2014 - engines tunning
Finally got new servos namely the TowerPro MG90s ones. Full metall gearing yey!
Modded one last night for continuous rotation keeping the electronics so it can be cotrolled just like regular servos.
To mod this type of servo you would do the following steps (yes I'll do a howto wiht pics) :
1. unscrew the 4 screws
2. remove the output gear (the last one) from the pot shaft
3. use a 1.5 mm drill to drill out the shaft lock hole so the output gear can easyly turn around the shaft
4. cut the plastic tab located underneath the output gear
5. find the center of the pot as precise as possible and glue the shaft in place so it stays centered
6. put the thing back together and enjoy :)
I'll have to update the tensioner design again ... I found I was pushing the track way too much, I'll make it shorter.
Also will work on the cover so it looks nice :)
Update - 4.03.2014 - ain't called alpha for no reason
Found a bug in the track design, you will need 28 links using hard pla :/
Also the tensioner needs to be longer. ... so a bit of redesign is in order.
Later edit: files fixed in git ... printing now.
<--- older stuff below --->
New project in works for a while.
I have designed this one with the following in mind:
- printable by everyone not just me
- off the shelf motors and batteries - easy to source
- rpi + arduino nano + l293 (or what ever else fits) as electronics
- webcam as the main sensor - GroG mentioned rpi cam but I think it's a bit pricey and badly supported
- whatever else comes to mind
I have built a first prototype to test things out and it seems fine, so I think it's ready for some real world testing.
I'm using the RPI because of my own interests but the electronics can be changed to anything really.
The current state of this does not have an upper case part, I did not design it yet but it will be added when I get to.
Here is a (draft) BOM to get things going:
1. Printed parts:
1 x lower_frame.stl
1 x battery_pi_mount.stl
2 x track_spacer.stl
1 x track_panel_right.stl
1 x track_panel_left.stl
4 x tensioner_wheel.stl
2 x tensioner_upper.stl
2 x tensioner_lower.stl
2 x idler_wheel_interiour.stl
2 x idler_wheel_exterior.stl
2 x drive_wheel_interior.stl
2 x drive_wheel_exterior.stl
26 x single_track_link.stl per track so 52 in total
2 x continous rotation 9g microservos
3 x 18650 li-ion batteries - mine are 2000mAh ones
10 x 623zz bearings
2 x 45 mm long 3 mm diameter threaded rod
12 x 10 mm long 3 mm diameter screws (well I hope I counted well)
lots of 3 mm washers and nuts
2 x springs - ~8mm internal diameter , ~9 mm external diameter, ~ 16 mm in length - you'll probably have to experiment here
52 x 1.2 mm diameter, ~ 13 mm pins -- well anything goes here I used some steel wire
1 x raspberry py
1 x arduino nano + motor driver shield ( this is to be settled but is what I have in mind)
1 x webcam mine is an el cheapo logitech --- to be settled when we do the upper part
1 x 3A Ubec to stepdown to 5v
4. Build instructions:
Print all stuff, I used 0.2 mm.
Assemble as in renders below:
... and top view
I have setup a github repo here for the STL's not sure if it helps anyone to post the blend file:
<--- Older entries below --->
Some pictures from the build below:
And one track complete: