i still cant get my damn ultrasonic sensor to work as stated here (updated) on my robot akira
i was wondering if anyone knew of a hardware interference problem between sensors and servo's similar to this one but where the servo works fine but the sensor is unable to see a thing.
ill be doing a hardware module test to try and find any obvious problems (using the debug command to read the sensor) but frankly i did this beforehand and everything was just fine
but i was wondering
do i need more pauses in the program to allow for the sensor to work?
once the motors have been switched on do they create problems?
does anyone have a magic spell to make everything right?
thanks peeps (and a thankyou to all the shoutbox people who have been helping out too)
I’ve never used ultrasonic sensors, but I’m guessing Noise might have a large part to play with your problem. After having a quick look over your photo’s I noticed you haven’t soldered any capacitors across the motor terminals, generally with small motors a 01.uf cap soldered onto the motor terminals helps reduce the amount of electrical nosie they create. I’d also think that the sensor itself would probably need some filtering capacitors across it’s power wires.
i can understand that interference could create a slightly irregular signal - but would it create complete blindness?
the capacitor idea is something i may try later but for now a large part of me thinks ive made a stupid programming error so thats going to be my primary focus - nice spot on the link tho - some very usefull info on there
ultrasonics and servo correction AND forward motor = picaxe resets itself and goes back to the beginning of the program without even initiating the debug system
this is a bigger problem that just interference from the wires folks
just for the record - i used the simplest loop program i could build but with access to all gosubs and initial info
that does make more sense that the interference answer but surely 6 AA rechargeables running thru a 5v voltage regulator would sort this problem out - i mean ive seen many more bots easily handling servo + motors + sensor powered by 4.5v direct from the batteries (3 normal AA’s) - it just seems odd
the next direction i’ll be taking is to create a millisecond break in the forward motion motors either during servo movement (hopefully not - its hardly milli) or ultrasonic signal (more likely)
the thing is - this should not be happening - i have 7.2v (6 rechargeable AA’s) leading to a 5v voltage regulator - this should easily cover any current needed by such tiny motors and servo
the picaxe (28x1) is on the standard project board, i tested the reset pin and thats just fine - im lost…
has ANYONE seen this before with constant running motors (rather than just movement till the next sensor input)?
oh - and if you have any hints on programming this it would be appreciated (dont want my program to turn into an unreadable mess - its still linked and kept up to date here if you need a peek)
too much experimentation had run my batteries low - hence the cutout - it was probably above the picaxe requirements but below that of the voltage regulator when under pressure - this is why ive decided to build a stable power source next
anyway - back to square one - on the plus side several weeks banging my head on the wall found me a lot of programming mistakes so i might have more luck this time
