Script for ultrasonic sensor HC - SR04

[pmlapl]

Hi,
I’ve designed a hexapod and am considering using a Maestro controller. My problem is I have an HC-SR04 ultrasonic sensor for obstacle avoidance and I’ve not been able to find a Maestro script for driving it. I have an Arduino UNO that I could use and then feed the output to the Maestro but I’d like to simplify the build and use the Maestro only.

Help on writing a script or an example would be greatly appreciated. Thanks.

[JonathanKosh]

Hello.

The Maestro’s scripting language is very limited and not designed for accurately measuring pulse widths, so I do not think it would be suitable for that sensor. You might try reading the inputs with your Arduino Uno and then sending signals to the Maestro.

-Jon

[pmlapl]

Thanks. I guess that will have to do.

[herbert_koenig]

Hi,
strictly speaking you cannot use a HC-SR04 because for being able to use the full accuracy you would need a timer with 10us resolution and 50 ms max Duration which is not available on the Maestros.

But for practical purposes one resisor and one capacitor plus a script will do the trick.

Here

Using HC-SR04 range finder with Mini Maestros

Hi folks, just want to share how to use the HC-SR04 cheap ultrasonic range finder with the Mini Maestro servo controllers. Brief abstract: The HC-SR04 is used in continuous mode, one servo output is used to continuously trigger the senser with a short pulse (I use 25 ms). As the Maestro has no timer I filter the output of the sensor through a simple RC lowpass. This signal is then read via an analog input of the maestro. If you just need to measure the level in a water tank (signal changin…

I’ve documented it.
In case the links are not permanent, search “Share Your Projects” for HC-SR04 and Mini Maestros.

Cheers,

Herbert