hello everyone,
since i'm new here i will introduce myself first: i'm Merijn Otterman, secondary school student from the Netherlands. i'm interested in almost everything what has anything to do with movement or electronics.
for i project i'm working on i need an ultrasonic distance sensor wich will survive being outdoors for several days, the sensor will be mounted on a rc boat and needs to detect obstacles from at least 10 meters. are there any cheap options to achieve this? i thought about buying a cheap sensor like this. i thougt about just powering it with 12 volts so the transducer's output is bigger, so the overall working range will be bigger. but i think when supplying 12 volts to vcc you fry the amp from the receiver. so is it possible to search for the point where the input voltage is split between the transducer and reciever, cut the paths and apply 12 volts to the transducer and 5 volts to the receiver? if not, does anyone have some diy options to do something like this?
Your approach will not work. The module already applies more than 12V to the transducer.
I don't think it is possible to achieve 10 m range with consumer grade ultrasonic sensors, but a laser rangefinder like this one will work.
the problem with laserproducts, ignoring their price, is that the boat will be uses 24h, so also in bright sunlight. And laser is one point, since it also has to be able to detect bushes wich aren't solid surfaces. but this might work? with 40khz weatherproof transducer/receiver and higher voltage over the transducer then the 5v in this project?
but this might work?
Who knows? Try it, but be advised that the ultrasonic transmitter H-bridge circuit is a very bad design, and the receiver circuitry is not really different than that on the HCSR04.
The laser rangefinders I linked work in bright sunlight.
Edit: Maxbotix makes weatherproof sonar sensors with stated range of 10 m, but they are as expensive as the laser rangefinder. See the bottom of this page: Products – MaxBotix
jremington:
...advised that the ultrasonic transmitter H-bridge circuit is a very bad design...
What do you think is bad - no control of dead time?
Yes, it has severe shoot-through, and that calls in to question everything else.
jremington:
Edit: Maxbotix makes weatherproof sonar sensors with stated range of 10 m, but they are as expensive as the laser rangefinder. See the bottom of this page: Products – MaxBotix
yes i found that one, but wich one is better. because i think the laser is more precise. but isn't the small beam from the laser a problem with bushes as i described earlier?
Do you know that ultrasonic rangers will work with bushes? I would try both.
You may also want to consider an underwater transducer (forward looking depth sounder essentially) - for boats, there are always thing lurking just under the surface you need to watch for. Perhaps aimed down at 30 degrees or so for depth and collision avoidance. My new truck has some sort of sensor (not sure just what it is - more snooping required) that "sees" other vehicles ahead at least 100m or so. I know it has ultrasonic sensors for "parking assist" but those only seem to work 2-3 meters or so. Not sure what the vehicle detect is, but it does pick up any vehicle ahead quite a ways.