An interview from Heisha drone charging pad engineer
In the last few months, Heisha finished more than 100 units charging pad's production. The charging stability and safety are improved, and the adaptability of the DJI drones is strengthened.
An unattended UAV system is pretty complicated, which usually consists four parts: drones, recharging system, the base station, and the data analytics system.
Drones, if you design it by yourself, multiple parts need to take a lot of time, such as the flight control, the propulsion system, payloads and the flight safety. Even with the DJI drones, it also takes time for developing the DJI SDK.
The charging pad includes the charging system, precision landing and transfer the data to the public network and so on. It looks quite simply, but actually it takes lots of work to make it stable.
The drone box needs to be a complete cabinet so that during the unattended mission the drone can be safely charged and stored at the appropriate temperature and humidity. For example, the cabinet needs to be equipped with smart air conditioner, or solar power generation and other devices. It also requires a lot of time and development costs.
The analytics system, which is usually the most closely related to customer needs, must spend a lot of time to develop. Customization requirements are also the most demanding.
It would not be realistic for the system solution provider to do all the technology development themselves. 
So, we should open for partnership.
Heisha has provided C300 drone charging pad to a growing number of outstanding solution providers all over the world, helped them save time and cost, as well as improved the stability.

Heisha drone charging pad the 3rd generation