Help please

[wowowee]

hello,

i'm kinda new to electronics. i would just like to ask if the circuit below can measure the distance between the ultrasonic module and the obstacle? and how can i do it? this is for my project.

https://users.encs.concordia.ca/~dave/project/elec.html#Obstacle detection sensor

 

[Nigel Goodwin]

It's a simple sonar - you measure the time it takes for the reflection from the object. You can then calculate the distance based on how fast sound travels.

 

[wowowee]

It's a simple sonar - you measure the time it takes for the reflection from the object. You can then calculate the distance based on how fast sound travels.

thank you.. do you also know how to connect the circuit to pic16f877? where to connect it? should i connect it to a ccp pin?

 

[Nigel Goodwin]

Depends entirely on how you write the software? - a simple timing loop is really all that's required.

 

[wowowee]

okay. do you know anything about the "handy board digital port" in the diagram? the one on the extreme right of the receiver circuit. is it necessary to be connected to the collector of the transistor? i'm really sorry i'm really a noob when it comes to electronics.

 

[Nigel Goodwin]

okay. do you know anything about the "handy board digital port" in the diagram? the one on the extreme right of the receiver circuit. is it necessary to be connected to the collector of the transistor? i'm really sorry i'm really a noob when it comes to electronics.

It's the output from the ultrasonic receiver, it feeds to an input pin so you can detect it.

 

[wowowee]

It's the output from the ultrasonic receiver, it feeds to an input pin so you can detect it.

okay. so i can connect it to a microcontroller right? oh yeah, one more thing. do you know of a circuit that interfaces pic16f877 with an rs232? because i'm also gonna use it for the project. i'm gonna use pic16f877 with the ulrasonic module and interface it to a pc using an rs232 cable. i have researched some circuits of rs232, the one with a max232, but i don't really know if that is what i need. can you help me?

 

[Nigel Goodwin]

okay. so i can connect it to a microcontroller right? oh yeah, one more thing. do you know of a circuit that interfaces pic16f877 with an rs232? because i'm also gonna use it for the project. i'm gonna used pic16f877 with the ulrasonic module and interface it to a pc using an rs232 cable. i have research some circuits of rs232, the one with a max232, but i don't really know if that is what i need. can you help me?

Check out my PIC tutorials!.

 

[wowowee]

thanks again man. seems like i'll never run out of questions. what if there are two or more obstacles within the ultrasonic beamwidth? can it detect the all of it? or only the nearest one?

 

[Nigel Goodwin]

thanks again man. seems like i'll never run out of questions. what if there are two or more obstacles within the ultrasonic beamwidth? can it detect the all of it? or only the nearest one?

The nearest one!.

 

[wowowee]

okay. i think that's it for now. maybe in the next few days i'll have some more questions and i hope you can still help me with it. thanks again.

 

[wowowee]

hello again,

i tried to test the circuit in the link below but it didn't work. i rewired it a couple of times and still it didn't work. is there something wrong with the circuit? or is it the ultrasonic module that i'm using? i think its made from china.

 

[aoamb83]

insure that the ultrasonic module is working 1st this problem faced me before
good luck

 

[wowowee]

insure that the ultrasonic module is working 1st this problem faced me before
good luck

how would i know if the module is okay? do the pins of the module have polarities? which pin should i connect to gnd?

 

[Pommie]

That circuit is a simplified sonar. The output from it is logic high if an object is in front of it. It is only really useful for a robot that can use such limited information such as a maze solver. It cannot be used to measure distance.

Mike.

 

[wowowee]

That circuit is a simplified sonar. The output from it is logic high if an object is in front of it. It is only really useful for a robot that can use such limited information such as a maze solver. It cannot be used to measure distance.

Mike.

the output was a logic high when we used logic probes to the collector of the transistor. but how come the led didn't light up? do you know of an ultrasonic circuit that can measure distances?

 

[Pommie]

Sorry, my mistake, the circuit outputs logic low when an object is detected.

A quick google turned up **broken link removed**

Mike.

 

[wowowee]

Sorry, my mistake, the circuit outputs logic low when an object is detected.

A quick google turned up **broken link removed**

Mike.

thanks man.. can you say that there is something wrong with the ultrasonic module that i'm using? because the circuit in my link didn't work when i tested it.