My $26 WiFi tank arrived today. Erco was right, these are fun.
One thing I don't understand about this robot and many other commercial robots I've purchased is the lack of proportional control.
Several years ago I purchased a Roboni-I robot and found it only had forward/reverse/off control for both motors. This simplified the controller a bit but it sure limited the ability to control the robot. I made my own remote and converted the robot to proportional control and the bot behaved much better once I had made these changes.
At least the Roboni-I had an excuse not to include proportional control (the price of analog inputs vs. buttons (not a good reason to skip proportional control IMO)). These WiFi bots don't have any reason I can discern not to have proportional control. I'm be very surprised if the onboard microcontroller couldn't produce PWM output to control the motors and adding proportional input to the app is almost trivial. I really don't understand why they wouldn't make the firmware capable of proportional control.
Proportional control would have made these little robots even more fun.
I noticed the camera on this robot had four wires. This makes me wonder if it outputs an analog signal. I don't suppose any of you have looked at the signal with a oscilloscope?
If no one here has checked to see what sort of camera this is, I'll probably try to figure it out myself. I don't see many cameras this small with only four wires. Two of these wires are going to power supply lines so that just leaves two wires for the video signal. I'm wondering if one wire has a NTSC (or PAL) signal and the remaining wire is a separate ground for the analog signal. Do any of you have a guess about this?
I didn't look real close, but that ribbon cable going up to the camera also powers 2 white LEDs up top.
Right. I forgot about the LEDs. I'm going to bet the camera sends an analog signal.
If this is the case, then it's likely the a different camera could be substituted for the one it came with and it also means the little camera included with the tank could be used with other transmitters which take analog inputs. I'll need to investigate a bit more.
And thanks for my fabulous Toddler! The least I can do is apply some gentle arm twisting to my forum buddies when I know what they should buy better than they do.
I noticed the camera on this robot had four wires.
I miscounted the wires. There are five wires between the top camera section and the main PCB. Two of the wires control the two LEDs. One wire is ground, one is 3.3V and one is the video signal. I haven't tested the video signal yet but I'd be very surprised if it's not a NTSC signal.
I think having a NTSC camera interface makes the bot even more hackable. The camera can be used with other devices and other cameras could be used with the bot.
I wish my Android programming skills were better. I'd try to make a custom app but the WiFi and camera stuff is still beyond my present skill level.
Here are a few pictures of the camera module.
The five wire cable passes through the center hole and connects with the board on the other side.
The pads "P00" and "M00" are another place where ground and video are available.
The black camera module is 8mm x 8mm.
I this camera could be useful in other applications. I'm not sure what these applications are but I'll be on the lookout for them.
Today PayPal (obviously under erco mind control ) sends me an email good for $15 off a $50 ebay purchase....that means if I buy two of these robots and use my coupon, it's possibly too sweet a deal to pass up...
@Rick: Take two, they're small! You won't regret it. I'm sure Duane's ordering a second one as we speak.
@Duane: Nice teardown report! WRT changing cams, why? I think the image is great. Resolution of the cam prolly matches transmitter hardware, right? I can only think of ONE reason to change cams.
@Duane: Nice teardown report! WRT changing cams, why? I think the image is great. Resolution of the cam prolly matches transmitter hardware, right? I can only think of ONE reason to change cams.
I agree the picture is great. I was mainly curious if the camera produced an analog output. If the camera does output NTSC then one could overlay text using Phil's cool text overlay technique (hardware builtin to the Propeller Backpack).
I have video transmitters which use NTSC cameras but these all need a separate receiver. None of my WiFi transmitters allow one to swap out the camera so I thought it would be cool to have a WiFi video transmitter to use with other NTSC cameras.
I have a confession to make. My reason for wanting to order a second one wasn't just because I thought these were so cool and I wanted another one.
I let out the magic smoke of my first tank bot.
I was trying to figure out what voltage level was used by the microcontroller and my DMM probe shorted two of the pins. There was a small puff of smoke and the microcontroller chip got very hot.
The WiFi module wasn't connected when the microcontroller was killed so it should still be fine. I think most of the main PCB is also still usable but I'll likely remove the microcontroller and solder wires to various pads and use a Propeller to control the h-bridges.
I'm hoping the WiFi video stream is independent from the microcontroller. I'm concerned the WiFi module my require some initial configuration before it starts transmitting and I burned out the microcontroller before I captured any of the data exchange between the microcontroller and the WiFi module.
If the video doesn't stream independently then I'll likely need to purchase another bot in order to figure out how to configure the WiFi module.
Here's a picture of the PCB with the microcontroller.
The microcontroller has a large voltage range but I think this one was running off of 4.5V. I'm not sure if the h-bridges will work properly if I use 3.3V logic. If they don't, I'll add some level shifters between the Propeller and the h-bridge inputs.
Apparently letting out smoke and having the microcontroller too hot to touch didn't kill the thing. I'm very surprised and very pleased to have learn the robot still works.
I would speculate that the camera is digital out, As I think that camera can record onto a micro sd card.
Jim
I don't know. The SD card recording happens inside the phone. The robot itself doesn't record video. The WiFi module has to transmit digitized video so it's obviously digitized at some point on the robot. It seems like digital video is carried at such high bandwidths it requires special shielded wires.
No pity for fence-sitting non-buyers after a price increase. When erco says "buy", you say "how many?"
@Duane, my favorite hacker: Gald to hear your board survived. Here's another way to potentially misassemble and release more magic smoke: There are more pins on the WiFi board than on the mainboard socket, so when reassembling, align the OUTER pins along the PCB edge. The unused pins hang out in the breeze between the camera connector & raise/lower motor connector.
The house we just moved to has a crawl space, no basement.
Would be nice to have one of these with some LED's to look around down there, or be on standby duty.
Price is now $31.49. Am going to pull the trigger, probably get one of those cheap boroscopes as well.
Should be pretty easy to slap a cellphone batt on it somewhere to give it some more life right?
One mod I'd like to make is external charging port so it can back up to a charging pod at the crawlspace entry.
Now that I think about it, maybe move the guts to a small metal 'tank', add some extra batteries, stronger motors, a laser pointer and a CO2 BB semi-auto...*%&# chipmonks.
Yep. A bigger battery would def help. The wifi transmitter gets warm and consumes several hundred mA constantly, more than the motors. You could switch that off during charging, but on startup it takes about 20 seconds for the wifi signal to start.
Not sure how long this toy would last if on 24/7. Might need fan cooling.
As before, there are 6+ sellers in Hacienda Heights CA with exactly the same price. Was $26, now all $33.16-33.18. Tomorrowtop, ttstoreusa, tomtopmall, tomtop.usa. Either price fixing or the same seller.
Still a smoking deal at $33 IMHO. A lot of useful tech in a small package.
Actually the CX10W is the streaming video version, it works very well, other than the typical flying squirreliness of a tiny drone.
The little H2O hexacopters mentioned by E351 are much more stable than the little quadcopters.
The little quads are fun but not nearly as much fun as the little hexes.
Really, if any of you don't have these little hexes get a couple. They're lots of fun.
I counted how many of these little hexes we have the other day and counting the hexacopters still in their box I came up with 12. My wife thinks they make great Christmas presents so she had me get a bunch.
I'm waiting for my WiFi hex to arrive. I'm hoping the video is fast enough to do some indoor FPV flying.
Comments
One thing I don't understand about this robot and many other commercial robots I've purchased is the lack of proportional control.
Several years ago I purchased a Roboni-I robot and found it only had forward/reverse/off control for both motors. This simplified the controller a bit but it sure limited the ability to control the robot. I made my own remote and converted the robot to proportional control and the bot behaved much better once I had made these changes.
At least the Roboni-I had an excuse not to include proportional control (the price of analog inputs vs. buttons (not a good reason to skip proportional control IMO)). These WiFi bots don't have any reason I can discern not to have proportional control. I'm be very surprised if the onboard microcontroller couldn't produce PWM output to control the motors and adding proportional input to the app is almost trivial. I really don't understand why they wouldn't make the firmware capable of proportional control.
Proportional control would have made these little robots even more fun.
If no one here has checked to see what sort of camera this is, I'll probably try to figure it out myself. I don't see many cameras this small with only four wires. Two of these wires are going to power supply lines so that just leaves two wires for the video signal. I'm wondering if one wire has a NTSC (or PAL) signal and the remaining wire is a separate ground for the analog signal. Do any of you have a guess about this?
http://www.picaxeforum.co.uk/showthread.php?28858-wifi-module-for-iOS-and-picaxe&p=297954&viewfull=1#post297954
That's interesting. Maybe there's a chance a better app could be developed?
Right. I forgot about the LEDs. I'm going to bet the camera sends an analog signal.
If this is the case, then it's likely the a different camera could be substituted for the one it came with and it also means the little camera included with the tank could be used with other transmitters which take analog inputs. I'll need to investigate a bit more.
Thanks for talking me into getting one of these.
And thanks for my fabulous Toddler! The least I can do is apply some gentle arm twisting to my forum buddies when I know what they should buy better than they do.
I miscounted the wires. There are five wires between the top camera section and the main PCB. Two of the wires control the two LEDs. One wire is ground, one is 3.3V and one is the video signal. I haven't tested the video signal yet but I'd be very surprised if it's not a NTSC signal.
I think having a NTSC camera interface makes the bot even more hackable. The camera can be used with other devices and other cameras could be used with the bot.
I wish my Android programming skills were better. I'd try to make a custom app but the WiFi and camera stuff is still beyond my present skill level.
Here are a few pictures of the camera module.
The five wire cable passes through the center hole and connects with the board on the other side.
The pads "P00" and "M00" are another place where ground and video are available.
The black camera module is 8mm x 8mm.
I this camera could be useful in other applications. I'm not sure what these applications are but I'll be on the lookout for them.
Today PayPal (obviously under erco mind control ) sends me an email good for $15 off a $50 ebay purchase....that means if I buy two of these robots and use my coupon, it's possibly too sweet a deal to pass up...
Dang!!
@Duane: Nice teardown report! WRT changing cams, why? I think the image is great. Resolution of the cam prolly matches transmitter hardware, right? I can only think of ONE reason to change cams.
Thanks for all the info so far! Looking at this as a project to hack.
I was about to order a second one but I found the price had increased. Darn.
If any of you find one of these for $27 (or less (shipped)), let me know.
I agree the picture is great. I was mainly curious if the camera produced an analog output. If the camera does output NTSC then one could overlay text using Phil's cool text overlay technique (hardware builtin to the Propeller Backpack).
I have video transmitters which use NTSC cameras but these all need a separate receiver. None of my WiFi transmitters allow one to swap out the camera so I thought it would be cool to have a WiFi video transmitter to use with other NTSC cameras.
I plan to test this today. I'll need to solder up some adapters.
I have a confession to make. My reason for wanting to order a second one wasn't just because I thought these were so cool and I wanted another one.
I let out the magic smoke of my first tank bot.
I was trying to figure out what voltage level was used by the microcontroller and my DMM probe shorted two of the pins. There was a small puff of smoke and the microcontroller chip got very hot.
The WiFi module wasn't connected when the microcontroller was killed so it should still be fine. I think most of the main PCB is also still usable but I'll likely remove the microcontroller and solder wires to various pads and use a Propeller to control the h-bridges.
I'm hoping the WiFi video stream is independent from the microcontroller. I'm concerned the WiFi module my require some initial configuration before it starts transmitting and I burned out the microcontroller before I captured any of the data exchange between the microcontroller and the WiFi module.
If the video doesn't stream independently then I'll likely need to purchase another bot in order to figure out how to configure the WiFi module.
Here's a picture of the PCB with the microcontroller.
Here's a closeup of the microcontroller.
Here's a link to the microcontroller at Mouser.
The microcontroller has a large voltage range but I think this one was running off of 4.5V. I'm not sure if the h-bridges will work properly if I use 3.3V logic. If they don't, I'll add some level shifters between the Propeller and the h-bridge inputs.
Jim
Apparently letting out smoke and having the microcontroller too hot to touch didn't kill the thing. I'm very surprised and very pleased to have learn the robot still works.
I don't know. The SD card recording happens inside the phone. The robot itself doesn't record video. The WiFi module has to transmit digitized video so it's obviously digitized at some point on the robot. It seems like digital video is carried at such high bandwidths it requires special shielded wires.
I'll try to find out for sure.
http://www.ebay.com/itm/Wifi-i-spy-RC-Tank-Car-RC-Camera-Car-777-270-w-Camera-for-Phone-Controller-T7L7-/401105579862
Funny, there have been several SoCal sellers at $26, but it does appear that they all bumped up to around $33. Here's one for $31: http://www.ebay.com/itm/Wifi-i-spy-RC-Tank-Cars-777-270-w-30W-Pixels-Camera-f-iPhone-iPad-iPod-Superior-/111725617880
No pity for fence-sitting non-buyers after a price increase. When erco says "buy", you say "how many?"
@Duane, my favorite hacker: Gald to hear your board survived. Here's another way to potentially misassemble and release more magic smoke: There are more pins on the WiFi board than on the mainboard socket, so when reassembling, align the OUTER pins along the PCB edge. The unused pins hang out in the breeze between the camera connector & raise/lower motor connector.
If this is the explanation, we should see better prices eventually, as supply catches up.
I'll just take my business elsewhere!!!
Another option is Banggood. They charge $36. You get to choose your color from Banggood.
The house we just moved to has a crawl space, no basement.
Would be nice to have one of these with some LED's to look around down there, or be on standby duty.
Price is now $31.49. Am going to pull the trigger, probably get one of those cheap boroscopes as well.
Should be pretty easy to slap a cellphone batt on it somewhere to give it some more life right?
One mod I'd like to make is external charging port so it can back up to a charging pod at the crawlspace entry.
Now that I think about it, maybe move the guts to a small metal 'tank', add some extra batteries, stronger motors, a laser pointer and a CO2 BB semi-auto...*%&# chipmonks.
Not sure how long this toy would last if on 24/7. Might need fan cooling.
Still a smoking deal at $33 IMHO. A lot of useful tech in a small package.
I haven't looked at the signal with an oscilloscope but no image appears on a TV set connected to the video.
http://www.ebay.com/itm/Hot-HappyCow-777-325-Wifi-Remote-Control-i-TECH-Tank-with-0-3MP-Camera-Z7O4-/301966023757
micro quad-copter with camera
USD $22.30
http://www.ebay.com/itm/Hot-RC-Quadcopter-Mini-Drone-Presell-Cheerson-CX-10W-2-4GHz-4CH-6-axis-Wi-Fi-FPV-/231952021411
At $22.67 after discount, that's another rockin' deal!
The little H2O hexacopters mentioned by E351 are much more stable than the little quadcopters.
The little quads are fun but not nearly as much fun as the little hexes.
Really, if any of you don't have these little hexes get a couple. They're lots of fun.
I counted how many of these little hexes we have the other day and counting the hexacopters still in their box I came up with 12. My wife thinks they make great Christmas presents so she had me get a bunch.
I'm waiting for my WiFi hex to arrive. I'm hoping the video is fast enough to do some indoor FPV flying.