My name is Jacek Witalinski. I’m a glider pilot and the designer of a camera gimbal system for Sebastian Kawa’s Everest gliding event. I think some details of its construction and operation might be interesting to Café readers. The gimbal design and construction took me about two months.
On November 16, 2013, our pilot,Sebastian Kawa, a multiple world champion in gliding, and his team arrived in Nepal near the Himalayas to make the world’s first glider flight over Mount Everest. The glider has its own rotary engine for stand-alone start to a ceiling of 2000 m. The rest of the height he must gain by soaring.
The Everest project began about two years ago, but they had a lack of proper camera stabilization, which the gimbal I designed alleviates. This gimbal is designed for gliders and difficult high altitude mountainous environments. Among other requirements, the gimbal had to rotate 340 degrees and 170 degrees in yaw and pitch.
After analyzing all the factors that prevail during the flight at an altitude of about 8000 m, I determined that the more important were:
1. Temperatures as low as -60C
2. Jetstream speeds of 200 to 350 km/h
3. Battery life and effectiveness at low temperatures
4. And many others . . .
I designed an aerodynamic gimbal shape for the onboard GoPro 3+. The gimbal position is adjusted from a remote panel equipped with an LCD and control sticks. 2.4Ghz provides video streaming and 800 MHz RC.
The GoPro and ancillary devices are powered by the main Lithium ion battery located in the device. There was no question of using a mechanical connection such as cables, so everything must operate autonomously.
During the first tests in the air at the beginning of October, we found that yaw power was too small. After increasing the motor power, we could operate the gimbal at 120 km/h. After more testing and appending additional gear we reached 150 km/h with full operational capability. This is 20 km/h more than average cruise speed.
I found that the Lithium-ion batteries work at temperatures from -60 to +60C and produce 4000 mAh. To simplify the process of charging, I installed protection against overcharge and discharge for each cell below targets. This is not a balancer, but enough not to damage the battery during a long flight when the batteries become depleted below a critical voltage.
All electronic controller components were chosen to operate over a +/-50C temperature range. I set higher power to treat the coil of the yaw motor as a heater. The stabilization temperature lacked the time, but I think that’s enough.
All structures are made from carbon fiber to reduce weight while retaining maximum strength.
