Agricultural detection device and a detection method for sensing agricultural objects

1. An agricultural detection device comprising:

a sensor unit comprising a first sensor with a first directivity, the first sensor being configured to emit a first transmission signal and to receive a first reflection signal;

an evaluation unit; and

a control unit,

wherein the first sensor has a second directivity and emits a second sensor signal with the second directivity and receives a second reflection signal, or the sensor unit comprises a second sensor arranged adjacent to the first sensor with a second directivity for emitting the second transmission signal and for receiving the second reflection signal,

wherein the first directivity is smaller in width than the second directivity,

wherein the control unit switches between the first directivity and the second directivity,

wherein the evaluation unit ascertains at least a structure of plants, a height value and a density of the plants from the first reflection signal and the second reflection signal,

wherein the evaluation unit determines a horizontal distance between neighboring plants from the first reflection signal and the second reflection signal, and

wherein the sensor unit is provided on a spray boom of a field sprayer of a vehicle, the sensor unit being arranged adjacent to at least one spray nozzle of the spray boom.

2. The agricultural detection device according to claim 1 , wherein the first sensor is an ultrasonic sensor.

3. The agricultural detection device according to claim 1 , wherein the first directivity is a sound beam and wherein the sound beam has a width between 30 cm and 70 cm at a distance of 1 m to the first sensor.

4. The agricultural detection device according to claim 1 , wherein the second directivity is a sound beam and wherein the sound beam has a width between 80 cm and 120 cm at a distance of 1 m to the first sensor.

5. The agricultural detection device according to claim 1 , wherein the first sensor is an ultrasonic sensor, wherein the second sensor is a radar sensor with a detection field as the second directivity, and wherein the detection field has a width between 80 cm and 2 m at a distance of 1 m to the radar sensor.

6. The agricultural detection device according to claim 1 , wherein the first sensor is an ultrasonic transducer with a variable directivity.

7. A detection method for the detection of agricultural objects, the method comprising:

providing a sensor unit having a first sensor, an evaluation unit, and a control unit, the first sensor being operatively connected with the evaluation unit and the control unit;

emitting, via the first sensor with a first directivity, a first transmission signal at timed intervals and receiving subsequently, a first reflection signal; and

transmitting, via the first sensor with a second directivity or a second sensor disposed adjacent to the first sensor with a second directivity, a second transmission signal at timed intervals and receiving a second reflection signal,

wherein the first directivity is smaller in width than the second directivity,

wherein a height value, a structure of plants and a density of the plants are ascertained by the evaluation unit via the first reflection signal and the second reflection signal,

wherein the evaluation determines a horizontal distance between neighboring plants from the first reflection signal and the second reflection signal, and

wherein the sensor unit is provided on a spray boom of a field sprayer of a vehicle, the sensor unit being arranged adjacent to at least one spray nozzle of the spray boom.

8. The detection method according to claim 7 , wherein the second transmission signal is emitted via the second sensor, and wherein the first transmission signal and the second transmission signal are emitted simultaneously.

9. The detection method according to claim 7 , wherein the first transmission signals and the second transmission signals are emitted in alternation.

10. The detection method according to claim 7 , wherein the first transmission signals are generated by a first ultrasonic transducer.

11. The detection method according to claim 7 , wherein the second transmission signals are generated by a second ultrasonic transducer or by a radar sensor.

12. The detection method according to claim 7 , wherein, in the first and second reflection signals, a rising slope is ascertained via a slope threshold.

13. The detection method according to claim 12 , wherein, in the first and second reflection signals, a height value is ascertained via a height threshold.

14. The detection method according to claim 13 , wherein the height value is ascertained after exceeding the slope threshold and the height threshold.