Doable?!

Is it one of these: MB1010 LV-MaxSonar-EZ1 Ultrasonic Rangefinder

if so, there appears to be an RS232 connection. That might be the easiest.

No its MB7389 Outdoor Ultrasonic Sensors from MaxBotix Inc. same thing?!

Application Specific. Different applications require different ultrasonic sensors. We design our processes to manufacture ultrasonic sensors by the thousands. It’s that simple. Engineers and OEMs value our factory calibrations because once a product is selected they can move forward with their large-scale deployment without manually configuring each individual sensor.

Key Characteristics

• Simple Mounting
• Low Power Requirements
• Select from Multiple Outputs
• High Reading Stability
• Calibrated Beam Patterns
• Additional features on each product page

Featured Applications

• People Detection
• Remote Bin Measurement
• Automated Store Displays
• Water Level Measurement
• Parking Sensor
• More Applications

Although it could work, it depends on which one you choose. See LV-MaxSonar-EZ Quick Start Guide for some understanding. By far the best discussion is here If you have the one your friend gave/lent above, it is very doubtful.

Hope this helps,

Clem

It appears your range finder has a 4-20mA output, in which case you will require an ADC input to measure the distance and then eventually resolve that into volumetric measurement.  The rPi does not have ADC by default, and so you would require an expansion module, or you could use a BeagleBoneBlack as an alternative as it has a few 12-bit ADC.  Also, if your application only does is a simple measurement then conversion, you may just be ok using an Arduino or a TI Launchpad.  The CC3200 would be a great platform for this particular monitoring application.

Christever

Thank you for the info. I'll have to do a little more research. Appreciate your help

RaspberryPi may be a bit of overkill for this application - perhaps an arduino would be simpler...

Using a MaxSonar With an Arduino

Arduino Playground - MaxSonar

Yeah I didn't get the Rpi specifically for this application but when my buddy offered a sensor and challenged me to make it work... I managed to get it wired up by following the tutorial at Maxbotix. I was rather surprised I got it working. That being said, will it damage my Rpi due to the 4-20mA output? Would I be better off getting the TI Launchpad (CC3200) offered by Christever or one of arduino boards?  

The 4-20 mA signal can be converted to a voltage using a resistor between the signal and ground.

The MB7389 operates from power supplies between 2.7 and 5.5 volts.

If you are running from 3.3V to be compatible with the RPi, the 4-20 mA output cannot exceed the power supply voltage, so it wouldn't hurt the RPi inputs. If you are running from a supply larger than the internal RPi supply you may need to choose a resistor that limits the voltage. It is the same resistor in either case since you always want 3.3 v max. V=IR .... 3.3 = .02 * 165

So any resistor smaller than 165 ohms should work if my math is right. 150 ohms is the nearest common value. This value will generate 3v at full scale from the sensor.

Douglas,

Thank you for the info, new to all this so I get a bit nervous around voltage, resistors, etc. I was able to get the sonar operational, now to find/write code to convert mm to ounces from the sonar. Appreciate all the info/help.

Maybe the WiPy could be a good solution for you. The WiPy is a new CC3200 IoT development board which is python programmable and as they say super low power.