Ultrasonic sensor

Robotic kit for Raspberry Pi
1

Good evening, I’m testing Pidog by running the robot-hat/examples/ultasonic script. It works, and it shows me various distances. Running Pidog/examples/3-patrol.py always gives me -1 as the distance. The touch sensor always shows R.
Thanks

1 Like
2

Regarding the ultrasonic sensor always showing -1:When running pidog/examples/3_patrol.py, the sensor may return -1 because the head movement could cause the ultrasonic module’s cable connection to become loose. Please try reconnecting the cable on both ends.

Regarding the touch sensor always showing “R”:This is a known issue in older versions of the code. Please check your current PiDog code version by running:pidog -v

If your version is not 1.3.13 or newer, please update to the latest version by running the following commands:

cd ~/pidog
git pull
sudo pip3 install . --break-system-packages

After updating, reboot your PiDog and test again. The touch sensor should then behave correctly.Let me know if the issue persists after these steps.

3

Hi, I checked the cable, but I think it’s OK, also because the ultrasonic.py script works. The code version is 1.3.13.

4

Could you tell me on which PIDs the ultrasonic sensor and the dual touch sensor should be placed and their position in the v2 version board?

5

First, please check the robot-hat version and your HAT board version:pip3 show robot-hat

Does your Robot HAT PCB say V4 or V5?

We believe we have reproduced the issue. Please check your ultrasonic sensor wiring:

White → V5: GPIO 17 / V4: D0 Yellow → V5: GPIO 4 / V4: D1 Red → 3.3V Black → GND

After correcting the wiring, test with:

cd ~/pidog/examples
sudo python3 3_patrol.py

Does your Robot HAT PCB say V4 or V5?We believe we have reproduced the issue. Please check your ultrasonic sensor wiring:White → V5: GPIO 17 / V4: D0 Yellow → V5: GPIO 4 / V4: D1 Red → 3.3V Black → GND

After correcting the wiring, test with:

cd ~/pidog/examples
sudo python3 3_patrol.py

Note: robot-hat/examples/ultrasonic.py uses D2/D3, so it will return -1 with this wiring. Please ignore that example.

For the touch sensor (always shows “R”), please re‑seat its wiring:Green → V5: GPIO 27 / V4: D2 Yellow → V5: GPIO 22 / V4: D3 Red → 3.3V Black → GND

If it still shows “R” after re‑seating, we will send you a replacement.

6

Everything’s fine. Thank you so much.

7

Congratulations on solving the problem! If you run into any other issues in the future, please feel free to ask us.