Single Camera Suspended Rigs

Most single-camera mounting systems for kite or blimp aerial photography include the basic functions for camera position (pan and tilt) and shutter trigger, which are usually controlled by radio from the ground. In this relatively simple approach, no video downlink or other onboard equipment is involved in the mounting system. The camera position (pan and tilt) is estimated by visual observation of the camera from the ground, usually with binoculars, and by radio-control settings. Many pictures are taken to insure that the ground target is fully covered from appropriate viewing angles.

A typical, double U-shaped camera mount includes a cradle to hold the camera, a frame in which the cradle can be moved, and small servos to accomplish the movements (Fig. 7-2). Such a mount for a relatively small compact camera normally weighs around 0.5-1.0 kg, including the camera, batteries, and other components, with weight depending mainly on the specific camera model. Aluminum is the usual building material for the frame and camera cradle, although titanium, plastic, wood, fiberglass, or other materials may be used for lighter or stronger components (Fig. 7-3).

Another configuration for this lightweight approach involves a single vertical post as the main architectural element for the camera mount (Fig. 7-4). This rig has radio control of camera pan, tilt, and shutter trigger. The tilt servo and battery pack act as a counterbalance for the camera tilt mechanism.

The lighter-is-better theme reaches its ultimate development with a small electronic chip that is pre-programmed to change the camera position and trigger the shutter automatically. This may be done in a systematic manner or could be random in position and timing. In either case, this method completely removes any in-flight ground control of camera

FIGURE 7-2 Typical mounting system for a small digital camera. Aluminum frame and cradle held by a Picavet suspension. R, radio receiver and antenna mast (yellow); P, pan servo and gears; B, nickelmetal-hydride battery pack; T, tilt servo; and S, shutter-trigger microservo. Total weight of this rig with camera is just 0.6 kg. Originally built by B. Leffler (California, United States) with extensive modifications by JSA.

FIGURE 7-2 Typical mounting system for a small digital camera. Aluminum frame and cradle held by a Picavet suspension. R, radio receiver and antenna mast (yellow); P, pan servo and gears; B, nickelmetal-hydride battery pack; T, tilt servo; and S, shutter-trigger microservo. Total weight of this rig with camera is just 0.6 kg. Originally built by B. Leffler (California, United States) with extensive modifications by JSA.

Camera Suspended Frame

FIGURE 7-3 Mounting system for a mid-sized digital camera. Aluminum cradle for the camera is held in a titanium frame. The pan (P) and tilt (T) servos are relatively robust devices, and the shutter is triggered by a micro-servo (S). Total weight of this rig with camera is ~ 0.8 kg. Originally built by B. Leffler (California, United States) with extensive modifications by JSA.

FIGURE 7-3 Mounting system for a mid-sized digital camera. Aluminum cradle for the camera is held in a titanium frame. The pan (P) and tilt (T) servos are relatively robust devices, and the shutter is triggered by a micro-servo (S). Total weight of this rig with camera is ~ 0.8 kg. Originally built by B. Leffler (California, United States) with extensive modifications by JSA.

operation, which means that a radio receiver and antenna are not necessary on the camera rig.

Single-lens reflex (SLR) film or digital cameras are normally larger in size and heavier than point-and-shoot cameras and, thus, require larger mounting systems with stronger servos, bigger batteries, and other components. Total weight is typically >1.2 kg. Lens interchangeability means that longer lenses and filters may be employed. In fact, a large lens could be the heaviest single component of the camera rig, which might substantially affect the balance of the mounting system. In order to save moving parts that need precise adjustment, the shutter servo and lever may be replaced with an electronic shutter cable connected to a radio-controlled microswitch (Fig. 7-5). Alkaline camera

Picavet Rig Servo
FIGURE 7-4 Single-post mounting system for a small camera. P, pan servo and gears; A, antenna mast and radio receiver; S, shutter microservo; T, tilt servo and battery pack. Total weight of this rig with camera is less than 0.6 kg. Rig built by B. Leffler (California, United States).
Camera Suspended Frame

FIGURE 7-5 Mounting system for a digital SLR camera. Aluminum frame and cradle with pan and tilt controls similar to previous examples. The primary difference here is an electronic interface to control the camera shutter (S), which eliminates one servo. In this configuration total weight of the rig and camera is 1.3 kg; with a larger lens, weight may exceed 1.5 kg. Rig built by B. Leffler (California, United States).

FIGURE 7-5 Mounting system for a digital SLR camera. Aluminum frame and cradle with pan and tilt controls similar to previous examples. The primary difference here is an electronic interface to control the camera shutter (S), which eliminates one servo. In this configuration total weight of the rig and camera is 1.3 kg; with a larger lens, weight may exceed 1.5 kg. Rig built by B. Leffler (California, United States).

batteries could be replaced with lithium-ion batteries, depending on camera models; lithium batteries weigh about 40% less than alkaline and provide longer-lasting power.

Primary design criteria for the camera mounts presented thus far are lightweight, rugged components, and reliable camera operation. One consequence of this approach is that all components are exposed with little or no protection to the elements. The mount, electronic parts, and camera are potentially vulnerable to dust, debris, and water as well as possible damage during impacts with the ground or obstacles (Fig. 7-6). In actual practice, the authors have experienced only a few mechanical failures or damage for these types of camera mounts.

In some situations, however, more robust mounting systems may be favored in order to protect the camera

FIGURE 7-6 Results of a hard crash of the rig pictured in Figure 7-3. Tilt servo gear broken, titanium frame bent, and antenna wire (yellow staff) pulled out of the radio receiver. The camera and kite were undamaged, and the broken rig could be repaired in the field. Photo by JSA, May 2009.
Camera Suspended Frame

FIGURE 7-7 Two mounting systems with pan and tilt functions for digital SLR cameras designed for robustness, increased protection of all parts, and minimal requirements for disassembly. Frame and cradle from aluminum, camera triggered by electronic remote-control release. Rigs built by the technical workshop staff of Frankfurt University's Faculty of Geoscience and Geography.

FIGURE 7-7 Two mounting systems with pan and tilt functions for digital SLR cameras designed for robustness, increased protection of all parts, and minimal requirements for disassembly. Frame and cradle from aluminum, camera triggered by electronic remote-control release. Rigs built by the technical workshop staff of Frankfurt University's Faculty of Geoscience and Geography.

apparatus better from blowing dust, salt, or sand as well as other harsh environmental elements or difficult flying conditions. Figure 7-7 shows two sturdy, warp-resistant SLR rigs with pan and tilt functions, electronic shutter release, and heavy-duty batteries; both weigh > 2 kg with camera. Battery packs, radio receiver, microswitches, and in rig B also the pan servo, are enclosed in boxes for protection against dust, sand, and dampness. The servo and radio-receiver batteries can be switched off when unused and charged without removing via the socket outlets, minimizing the need for disassembly and handling wear for delicate parts. These rigs have been used successfully for many years by IM and JBR in semi-arid and arid conditions, mastering several near-crash situations without damage.

Champion Flash Photography

Champion Flash Photography

Here Is How You Can Use Flash Wisely! A Hands-on Guide On Flash Photography For Camera Friendly People!. Learn Flash Photography Essentials By Following Simple Tips.

Get My Free Ebook


Post a comment