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URM V3.2 Ultrasonic sensor

URM3.2_Mannual_Rev2.pdf306.71 KB
Vendor's Description: 

URM37 V3.2 Ultrasonic Sensor uses an industrial level AVR processor as the main processing unit. It comes with a temperature correction which is very unique in its class.

Direct control through RS232, easy to control by PC.



Power: +5V
Current: <20mA
Working temperature: -10 ~ +70 C
Detecting range: 4cm-5m
Resolution: 1cm
Interface: PWM, RS232 or TTL (via Jumper)
Servo control: One servo control output
Operating Mode: Serial (PWM) passive control mode; Autonomous Mode; On/OFF Mode
Temperature sensor: 12 bits reading from serial port
Size: 22mm × 51 mm

Weight: 30g 



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Thanks for the info - following your instructions i now have managed to link my Arduino Mega (easier with 4 serial ports) to the URM37.

And Yes it works very well indeed - distance works - temparature reading works.

Servo Control also works.........wow weeeee . now thats cool for my scanning servo distance-ing mechanism.

It threw me for a bit -  but you have to include a checksum (sum) at the end of the serial stream....(now its so simple).

Very happy to see it works...... .And nice work as well!

The latest version has jumpers to switch between TTL and RS232 level output. More detail can be found at:



This Does not really help me or answer my other questions........ as mine has no jumpers.

"Mode 1: Serial passive control mode
Under this mode, the sensor is always waiting for command from serial port. Every time it receives a
command, it will return the distance and wait for the next command. The degree in the command will be
used to control a servo motor to rotate corresponding degree."

Okay, that sounds cool. Write "hey, sensor, gimme a reading at 3 o clock" and it'll move its own servo and answer back. One less servo to drive from the main brain.

Looks like 5-6 degree resolution, but says "270 degree scanning area". None of my servos turn 270 degrees. What am I overlooking here?

I have servos that turn 270 degrees but they work within the same range of values that my other servos do, just less resolution. You just have to experiment with what range your servos will handle. You might find that your servos will still accept the same values but give better resolution.
I asume this is a typo and it is 4-5m range?

Looks like 4cm to 5m, not 4 to 5 cm.

That's a helluva spread. Wonder how accurate it is at those extremes, and just where a "sweet spot" might be.

Sorry, still on my first cup of coffee :/

I can recommend both this module and the supplier YeRobot. Very Fast delivery (EU)and v.good communications.

I am using this sensor on my latest Bot  Mr.Flex  for obstacle detection.

He also has some other interesting goodies on his site.