Payload Development Criterion
To ensure the safety of aircraft when carrying payload devices to perform flight tasks, please follow DJI's payload criterion when using PSDK to develop payload devices.
Hardware Interface Standard
Notes
- DO NOT short the pins of the aircraft or the hardware platform.
- DO NOT Connect the aircraft to a power output system or input current to the aircraft.
- The load capacitance needs to be ≤500uF. If it exceeds this threshold, the aircraft will trigger short-circuit protection at the moment of power-on, and the SDK power supply will turn off the output.
- The protective current is 4A. If the current exceeds, the aircraft will cut off the power to ensure the flight safety.
- E-Port Lite only supports Matrice 3D/3TD and Flycart 30 models.
- Mavic 3E/3T and M30/M30T models only provides an E-port to expand development and connect PSDK payload.
- M300 RTK provides PSDK interfaces and OSDK Interface to expand development and connect PSDK payload. Accessories that can be used with the PSDK interface are SkyPort V2 and X-Port. Accessories that can be used with the OSDK interface are SDK round ribbon cable and OSDK expansion module.
- M300 RTK PSDK Interfaces includes one top-mounted gimbal port and two bottom-mounted gimbal ports. For details, please refer to Device Connection.
| Interface Pins | Development Accessories | Indicator Requirements |
|---|---|---|
| E-Port | Power Output | 24V / 4A (M350 RTK) |
| 16.8V-25.5V / 3A (Matrice 4D/4TD) | ||
| 12.8V-17V / 3.38A (Matrice 4E/4T) | ||
| 12V-17V / 3.26A (Matrice 3D/3TD, Mavic 3E/3T) | ||
| 19.2-26.1V / 4A (Matrice 30/30T) | ||
| PPS Pin Voltage | ≤ 3.3V | |
| UART | Follow the 3.3V TTL protocol | |
| USB | Follow USB 2.0 protocol | |
| E-Port Lite | Power Output | 5V / 2A |
| USB | Matrice 4E/4T/4D/4TD support USB 2.0 protocol, other models Follow USB 2.0 protocol | |
| Payload Port | Power Output | 13.6V / 2A (X-Port) |
| 13.6V / 4A (SkyPort V2) | ||
| High Power Output | 17V / 2.5A (X-Port) | |
| 17V / 4A (SkyPort V2) | ||
| High Power Application | 0-3.3V | |
| PPS Pin Voltage | ≤ 3.3V | |
| UART | Follow the 3.3V TTL protocol | |
| LAN | Follow the LAN IEEE802.3 protocol | |
| FlyCart 30 Payload Port (Power Supply Port) | Power Output | 42-60V / 9A |
| OSDK Port | Power Output | 24V / 4A (M300 RTK) |
Interference Compatibility Requirements
| Item | Compatibility Requirements |
|---|---|
| Light Source Flashing | If the payload is built-in a light source, the light source flashing frequency of the payload cannot be between 0.2 and 50 Hz. |
| Light Wave Emission | The payload cannot emit light with wavelengths between 600 and 700 nm. |
| Magnetic Field | The payload should minimize magnetic interference, including but not limited to interference created by ferromagnetic substances producing high-intensity alternating magnetic fields. |
| Electromagnetic Noise | • The payload should not transmit electromagnetic waves in the 1 - 1.7 GHz, 2.3 - 2.6 GHz, and 5.7 - 5.9 GHz bands. • The equivalent isotropic radiated power (EIRP) of the payload should be less than 1W. |
| Acoustic Noise | The payload should not transmit or generate 2.5-4 KHZ or 35-45 KHz band sound waves. Notice: When developing audio output payloads, such as speakers, avoid sound frequencies between 2.5-4 KHZ to prevent resonance with aircraft components that could lead to safety risks. For design recommendations, please contact us for details via email at dev@dji.com. |
Structural Design Standards
Notes:
- To prevent the payload device mounted on the aircraft from being affected by the flight inertia of the aircraft, hitting the battery compartment and blades, and damaging the aircraft or the payload device, please design the size of the payload device reasonably.
- To prevent the payload device from affecting the moment of inertia of the aircraft, please minimize the size of the payload device.
Common Structural Standards
Note: The data in the table below comes from the user manuals of aircraft. For more data, please go to the DJI official website, and search the target model and click "download". The User Manual is under the "Manuals" title. Foe example, Mavic 3 Enterprise Series User Manual.
| Structural parameters | Matrice 4D/4TD | Matrice 4E/4T | Matrice 3D/3TD | FlyCart 30 | Mavic 3E/3T | Matrice 30/30T | M300 RTK | M350 RTK |
|---|---|---|---|---|---|---|---|---|
| 3D Model | Please contact the technical support team to obtain | Please contact the technical support team to obtain | M3D/M3TD model | Contact SDK technical support team to get the 3D model | M3E model | M30T model | M300 RTK model Zenmuse H20 model Zenmuse H20T model Zenmuse H30 model Zenmuse H30T model | M350 RTK model Zenmuse H20 model Zenmuse H20T model Zenmuse H30 model Zenmuse H30T model |
| Structural Interference | Prohibit the payload equipment from colliding with various components on the drone when the drone is performing a flight mission. | |||||||
| Vibration | After the drone is powered on, in a stationary state, the payload device cannot generate vibrations that affect the IMU (you can view the IMU status on the DJI Pilot or Mobile App). | |||||||
| Case Temperature | Perceived temperature ≤50° C | |||||||
| Weight | The maximum load weight of the aircraft cannot exceed 220 g. | The maximum load weight of the aircraft cannot exceed 190 g. | PSDK payload 130 g Parachute 70 g | If the device is loaded two batteries, the maximum load weight is 30 kg. | The maximum load weight of the aircraft cannot exceed 130 g. If 4G Dongle is considered, the maximum load weight of the aircraft cannot exceed 100 g. | Do not exceed the maximum load weight of the aircraft: 230 g. | The maximum load weight of the aircraft cannot exceed 2.7 Kg. When using the gimbal bracket, the weight of the payload device that can be mounted on a single gimbal must not exceed 930 g. | If the aircraft is loaded two batteries, the maximum load weight is 2.73 kg. When using the gimbal bracket, the weight of the payload device that can be mounted on a single gimbal must not exceed 960 g. |
| Height | - | The height of the PSDK payload must not exceed 70 mm. | - | If used with DJI Dock, it should be less than 10 cm. | - | - | ||
| Movement Track | The motion trajectory of the load equipment should not cover sensors and ventilation holes. 1. The field of view of the front vision sensors is vertical -95° to 95°,horizontal -90° to 90°. 2. The field of view of the rear vision sensor is vertical -95° to 95°,horizontal -70° to 70°. 3. The field of view of the lateral vision sensor is vertical -53° to 53°, horizontal -45° to 45°. | The motion trajectory of the load equipment should not cover sensors and ventilation holes. 1. The field of view of the front and rear vision sensors is 90° × 90°. 2. The field of view of the up-looking vision sensor is 90° × 90°. 3. The field of view of the downward-looking vision sensor is 95° × 110°. 4. The field of view of the left and right vision sensors is 104° × 90°. 5. The air inlet of the Matrice 4E/4T is behind the gimbal, and the air outlet is above the aircraft battery. | The motion trajectory of the load equipment should not cover sensors and ventilation holes. 1. The field of view of the front and rear vision sensors is 90° × 90°. 2. The field of view of the up-looking vision sensor is 90° × 90°. 3. The field of view of the downward-looking vision sensor is 95° × 110°. 4. The field of view of the left and right vision sensors is 104° × 90°. 5. The air inlet of the Matrice 3D/3TD is behind the gimbal, and the air outlet is above the aircraft battery. | The motion trajectory of the load equipment should not cover sensors. 1. The detection range of binocular sensing system is 90° x 180° (horizontal x vertical). The perceptible distance is 0.5 - 29 m. 2. The detection range of front millimeter-wave rotating radar is 360° x ± 45° x ± 45°（horizontal x vertical x upward）. The perceptible distance is 1.5 - 50 m. 3. The detection range of back millimeter-wave rotating radar is 360° x ± 45° (vertical x horizontal). The perceptible distance is 1.5 - 200 m. | The motion trajectory of the load equipment should not cover sensors and ventilation holes. 1. The field of view of the front and rear vision sensors is 90° × 103°. 2. The field of view of the up-looking vision sensor is 100° × 90°. 3. The field of view of the downward-looking vision sensor is 130° × 160°. 4. The field of view of the left and right vision sensors is 90° × 85°. 5. The air inlet of the Mavic 3E/3T is behind the gimbal, and the air outlet is between the two up-looking version sensors. | The motion trajectory of the load equipment should not cover sensors and ventilation holes. 1. The front and rear vision sensors are tilted upwards by 8 degrees, and their field of view is 70° × 55°. 2. The left and right visual sensors are tilted upward by 11 degrees, and their field of view is 70° × 55°. 3. The top visual sensor has no inclination, and its field of view is 55° × 70°. 4. The downward visual sensor has no inclination, and its field of view is 70° × 55°. 5. The field of view of the six-direction infrared sensor is 30°. 6. The air inlet of the M30 series is behind the gimbal, and the air outlet is behind the fuselage/above the battery. | The motion trajectory of the load equipment should not cover sensors and ventilation holes. 1. The field of view of the front and rear vision sensors is 70° × 56°. 2. The field of view of the up-looking vision sensor is 64° × 79° .. 3. The field of view of the downward-looking vision sensor is 56° × 70° . 4. The field of view of the left and right vision sensors is 79° × 64° . 5. The field of view of the six-direction infrared sensor is 30°. 6. The range of 5cm from the bottom and top of the drone body is the air inlet and air outlet. | |
| Center of Gravity | Use the PSDK interface to mount the payload device, and the center of gravity of the payload device must be within the 20mm of the center of the PSDK interface. | Use the PSDK interface to mount the payload device, and the center of gravity of the payload device must be within the 30mm of the center of the PSDK interface. | Use the built-in screw holes to mount the payload device. Ensure the payload's center of gravity is located between the front and rear mounting holes, with the overall center of gravity maintained within 1 cm of the midpoint of the rear mounting holes. | Using a support structure below the parachute to secure the payload device, the center of gravity of the payload device needs to be located at the center of the parachute module. | Use the PSDK interface to mount the payload device, and the center of gravity of the payload device must be within the 30mm of the center of the PSDK interface. | Use the PSDK quick release bracket to mount the payload device, and the center of gravity of the payload device must be on the vertical line of the center of the quick release bracket. | Use the gimbal bracket to mount the payload device, and the center of gravity of the payload device must be within the orthographic projection area of the gimbal bracket. | |
Construction Standard for X-Port
X-Port's Structural
Figure below display the dimension of X-Port.
Figure. The dimension of X-Port（unit：mm）
Payload's Structural
Before designing the structure of the payload, please choose a tripod, if the size of the payload is limited by the tripod.
| Gimbal Type | Pitch axis rotation limit (Idle speed) | Landing Gear Type | X-Port payload structure limitation |
|---|---|---|---|
| Single gimble platform | Restricted | Original | The distance between the lower surface of the payload and the pitch axis is not more than 54mm. |
| Long | The distance between the lower surface of the payload and the pitch axis is not more than 72mm. | ||
| None | Original | The payload must in the mass center, which the diameter of the ball is 118mm. | |
| Long | The payload must in the mass center, which the diameter of the ball is 154mm. | ||
| Double Gimbal | Restricted | Original | The distance between the lower surface of the payload and the pitch axis is not more than 45mm. |
| Long | The distance between the lower surface of the payload and the pitch axis is not more than 63mm. | ||
| None | Original | The payload must in the mass center, which the diameter of the ball is 100mm. | |
| Long | The payload must in the mass center, which the diameter of the ball is 136mm. |
The requirements of the payload which is mounted on the X-Port are as follows:
- The width of the pitch on the X-Port is 80mm. The width of the payload couldn't exceed the wheelbase.
- The weight of the payload must be lighter than 450g otherwise the payload may damage the gimbal or the pressure-reducing ball.
- The centroid of the normal payload must be on the axis line of X-Port， and the payload couldn't strike the X-Port when the payload raised to 45°. The centroid of the payload must on the axis line when the payload’s zoom is in the maximum factor.
- If the payload touches the ground， please use the Long Landing Gear.
- Be sure that the port of the payload is completely flat, ensure that the waterproof could be sealed completely.
- The shell of the payload could be aluminum alloy. A plastic or carbon case is not recommended.
Custom Data Transmission Standard
| Type | Direction | Limitation |
|---|---|---|
| Command Channel | Mobile App ➟ Payload | ≤4096B/s |
| Payload ➟ Mobile App | ||
| User Payload Device ➟ Payload | ||
| Payload ➟ User Payload Device | ||
| Cloud (like Cloud API) ➟ Payload | ||
| Payload ➟ Cloud (like Cloud API) | ||
| High-speed data transmission channel (Only applicable for M300 RTK) | Payload ➟ Mobile App | Single Gimbal：≤ 8192Kbps Double Gimbals：other ≤ 4096Kbps |
Video Stream Transmission Standard
Use PSDK to develop the Payload must select one of the two H.264 standard.
Custom-H264 standard
Characteristic
- Standard H264 standard stream is more common and easier to obtain.
- When using this video stream format to send the code stream, it will be transparently transmitted to the App terminal through the aircraft for decoding, and the real-time code rate must not exceed the feedback value.
- Use this format to transmit the video stream, and the SEI content can be transmitted to the App.
Criterion
The camera payload device developed based on PSDK, when using the Custom-H264 standard, need to pay attention to the following key configuration information:
| Item | H.264 Item | value |
|---|---|---|
| The maximum video resolution | - | ＜1920 × 1080 |
| The maximum frame rate | - | ＜30fps |
| The maximum bit rate | - | ＜8Mbps |
| The recommended video aspect ratio | - | 4: 3 |
| The GOP encoding structure must use Period I | - | - |
| Level | Level Number | ＜5.1 |
| profile_idc | 7.3.2.1.1 | Baseline=66，Main=77，High=100 |
| YUV420 Format | 7.3.2.1.1 | chroma_format_idc=1 |
| 8Bit video | 7.3.2.1.1 | bit_depth_luma_minus8=0 bit_depth_chroma_minus8=0 |
| Not allowed customization,Scaling Matrix | 7.3.2.1.1 7.3.2.2 | seq_scaling_matrix_present_flag=0 pic_scaling_matrix_present_flag=0 |
| Only supports frame format encoding, not field encoding | 7.3.2.1.1 | frames_mbs_only_flag=1 |
| Only P-frames and I-frames are allowed, and P-frames have a single reference frame | 7.3.3 7.3.2.2 7.3.3 | slice_type = 0 or 2 num_ref_idx_l0_default_active_minus1=0 num_ref_idx_active_override_flag=0 |
| Not support Muti-Slice Group | 7.3.2.2 | num_slice_groups_minus1=0 |
Note: When using the H.264 encoding standard, the GOP encoding structure must use Period I (intra-frame encoded frames, one IDR frame will be inserted every 1 second to ensure that image data can be recovered if lost).
DJI-H264 standard
Characteristic
- The more stringent DJI H264 standard stream standard.
- When using this video stream format to send the code stream, it will be transcoded by the aircraft. Within the maximum code rate limit, the code rate can be dynamically adjusted according to the real-time image transmission link to achieve the best image transmission display effect.
- When using this format to transmit the video stream, the SEI content will be discarded by the aircraft and cannot be transmitted to the App.
Criterion
When using the camera payload device developed based on PSDK, when using the DJI-H264 standard, you need to pay attention to the following key configuration information:
| Item | H.264 Item | value |
|---|---|---|
| The maximum video resolution | - | ＜1920 × 1080 |
| The maximum frame rate | - | ＜30fps |
| The maximum bit rate | - | ＜8Mbps |
| AUD information must be added at the end of each frame | - | fixed 6 bytes: 0x00 0x00 0x00 0x01 0x09 0x10 |
| The recommended video aspect ratio | - | 4: 3 or 16:9 |
| The maximum byte size of a stream | - | ＜256KBytes |
| Level | Level Number | ＜5.1 |
| profile_idc | 7.3.2.1.1 | Baseline=66，Main=77，High=100 |
| YUV420 Format | 7.3.2.1.1 | chroma_format_idc=1 |
| 8Bit video | 7.3.2.1.1 | bit_depth_luma_minus8=0 bit_depth_chroma_minus8=0 |
| Not allowed customization,Scaling Matrix | 7.3.2.1.1 7.3.2.2 | seq_scaling_matrix_present_flag=0 pic_scaling_matrix_present_flag=0 |
| Only supports frame format encoding, not field encoding | 7.3.2.1.1 | frames_mbs_only_flag=1 |
| Only P-frames and I-frames are allowed, and P-frames have a single reference frame | 7.3.3 7.3.2.2 7.3.3 | slice_type = 0 or 2 num_ref_idx_l0_default_active_minus1=0 num_ref_idx_active_override_flag=0 |
| Not support Muti-Slice Group | 7.3.2.2 | num_slice_groups_minus1=0 |
| Long-term reference frames are not supported | 7.3.3.3 | long_term_reference_flag=0 |
| The decoding order is required to be consistent with the playback order | E.1.1 | max_num_reorder_frames=0 |
| Limit the number of decoded reference frames to 5 | E.1.1 | max_dec_frame_buffering=5 |
| The maximum number of reference certificates supported is 1 frame, and the maximum reference interval is 1 | 7.3.2.1.1 | max_num_ref_frames=1 |
Note:
- When using H.264 encoding standard, Gop structure is optional, which is Period I or GDR.
- If it is Period I, each I frame is required to be an IDR frame. If it does not meet the requirements, there is no guarantee that the image transmission can be recovered from the packet loss error; Send After finishing SPS/PPS, immediately transmit the stream of frame I, and then transmit AUD. There is no AUD information between SPS/PPS and slice. In the Period Ⅰ structure, it is recommended to have an IDR per second.
- If it is GDR, sps/pps need to be transmitted in each GDR refresh frame.
Compatibility Note: If the video stream format is set to DJI H264 format, data transmission function will not be available, it is recommended to switch to SDK interconnection function use.
Reference: H.264 Protocol
Video stream check tool: Stream check tool