Cool, you should post this
Cool, you should post this as a robot on LMR!
RE:
I try to avoid posting stuff involved with other robotics groups. (There’s a big red led sign in the background flashing their web address in the kid/nascar video) But I’ll post more robots, and the maze video’s, as they aren’t as obvious with the other groups name, as the above mentioned video is.
I have built a wall racer/radio control conbination
Thanks you Fritsl for this great idea! In hopes of getting more control over the steering and the wheel speed I built your racer on a hobby level car. It toggles between RC control and autonomous control.
Everything you said about the difficulties of heavier and faster models came true. Here is a video of the first attempt at the race track of our local RC car hobby shop.
http://www.youtube.com/user/kenjones1935#p/a/u/0/seDKRDUdehE
Ken
Cool!It is really hard to
Cool!
It is really hard to hear what you are saying on the video 
However, it looks to me that you are not having the problems with the heavier & faster car, but the programming. I remember my very first attempts driving the same way, in bows from the wall.
That is why I programmed as I did, I think you should have a look at the code, it is short, and there is a reason for every bit of it
Your code. I used it!
I used fritsl code on a toy level car a la your design, but my PIC would not drive the relay coils. While waiting for the SN7407N current driving DIPs to arrive by POST, I moved the code to a hobby level car that has an Electronic Speed Control. That is what is in the video. The problem with response time (I am guessing now) is my inability to program the 16F887 to make a Pulse Modulated Wave signal at 50 pulses per second frequency. The PIC can do PWM, but it tends toward repetition closer to 500 pulses per second. At that ‘out of radio control spec’ pulse rate I have not been able to moderate the wheel speed. The ESC can sort out pulse size for wheel travel Forward, Stop, and Reverse, but it seems only to go Bang/Bang - no gradation. I do not know the electronics of the ESC.
Thanks for a great idea. My goal is to hook middle school students into an interest in science and math.
Ken
It can be extremely hard to
It can be extremely hard to program up to an ESC; They usually have some form of "intelligence", that can be very hard to code.
I recommend that you start by making sub routines that do the stuff you want; Turn, stop, drive, reverse… And maks sure that each can be called right after the other, and do what it is supposed to. Usually this takes variables to changegradually within the routine.
I warn you though; this may be very hard. They react strange, and do not like fast changes. However, this way you will be sure that you can concentrate on the fun afterwards. Or make sure where your problem is
The RC car under PIC control works better than before
Below is a video which captures my RC car running both under PIC control and RC control. There is still much to be done to make this thing robust and reliable. This is a start.
http://video.yahoo.com/watch/7169550/18673820
Thanks for your interest.
Ken
How nice, congrats!You
How nice, congrats!
You should really post this as a robot now, so all the progress and info can be found there, and not on my post
BTW; Either it is because of inteference, or your code has some problems; It looks as if the SRF05’s are only making a very few readings pr second? (I count the blinking that I can see)
I started a new thread
Per the fritsl’s suggestion I am moving my comments to a new thread.
It is in the Specific System Related/ microchip MPLB forum.
The name is “Wall Following RC car using 16F887”.
Thank you fritsl for the idea and for your help.
Ken
I am studying this racing
I am studying this racing car project and also the code but with the Picaxe editor and the “wall_racer.bas” I’m having a syntax error on line 128 where it says: rev: Can you give me a hint,because I’m new to Basic and I’ve tried a few alt on that line already and it didn’t work…
Got my 4 DPDT micro relays.
Also is there a possibility to reduce the speed of these R/C motors? Thanks.
I’ve deleted that line 128
I’ve deleted that line 128 and it works…thanks.
Cool. As for your other
Cool. As for your other question, if you post your work in progress it will be much easier to help you; More info means better answers
Looking forward to see your project!! Are you making one or two?
Thanks frits
I’ve made my first robot and you can see it on my avantar icon. I wanted to see if I could make it work and it does but it’s very basic for my first one.I will post it. The racer would be just an idea because I have a 4x4 R/C without the transmitter. Also something on tracks would be great as a futur project too…so I’m on LMR everyday reading and watching other’s projects and I’m learning with you people. Thanks again this is a great discover for me.
Korel
Actually I can not see on
Actually I can not see on your avatar icon that you have made any robots. Have you marked it as “Draft”, perhaps?
hupssssssss it’s now
hupssssssss it’s now
omg omg its sooo cooooooool
omg omg its sooo cooooooool i wan to make 1 too!!!
Switch SRF04 for SRF05?
Would the SRF04 work for this project because it is much cheaper than the SRF05( 3x less on ebay). Would the connection and code be different? I am back after 3 years of absent so I want to give the wall racer a second attempt. Thanks
The SRF05 tech manual says:
"The SRF05 is an evolutionary step from the SRF04, and has been designed to increase flexibility, increase range, and to reduce costs still further. As such, the SRF05 is fully compatible with the SRF04. Range is increased from 3 meters to 4 meters."
I have had very good luck with the SRF05’s but they are the most expensive part of this project. Give the SRF04’s a shot if you like and report to the forum how they work.
Ken
Thanks Ken. I’ll give it a
oh my mistake. the one on ebay is not the SRF04 but it was the
Arduino Ultrasonic module HC-SR04 distance sensor. Would this still work?
I have no knowledge of the HCSR04, but…
I know of a person who made a wall racer using Arduino. The sonar distance sensor he used (it might not have been this HCSR04 at all) gave him inconsistent information. I do not know why. There could have been a number of reasons for his problem.
Ken