Storage Batteries Ebooks Catalog
Both SBS-3 and ANIK-C3 were cylindrical drums, measuring 2.7 m tall and 2.1 m wide when stowed on board Columbia, but increasing to more than twice that height in their final configuration. Both were coated with black 'skins' of 14,000 solar cells, which generated 1,100 watts of DC power to operate them over decade-long lifespans and also carried their own supplies of hydrazine fuel for station-keeping. Each had an onboard power system, including rechargeable batteries, to run its communications equipment. SBS-3 covered the entire contiguous United States and ANIK-C3 virtually all of Canada, including its remote northern regions.
To be able to operate your equipment reliably during the night you will have to have an independent power supply. For many people, this can be your car battery. Many cars now come with a second 12-volt DC power plug in the trunk for operating things like computers, camping equipment and telescopes. I wanted to be able Figure 2.10. 12-volt, 480-amp battery, 400-watt inverter, and battery charger. Image by author. Figure 2.10. 12-volt, 480-amp battery, 400-watt inverter, and battery charger. Image by author. to operate without my car, so I purchased a simple discount automobile battery. The battery supplies 480 cold-cranking amps of DC power, which is plenty to run my scope, CCD camera and laptop all night long on one charge. The telescope draws AC power from an inverter that is supplied with DC input from the battery. The CCD has no power source of its own and the computer battery is only good for a very short period of time. That time will be even shorter if the CCD needs to draw...
Of the alignment target to find the point at the top of that house. I will then switch to a high-power eyepiece and center it again in the main scope. When that is done, I will then carefully use the three setting screws in the finder scope bracket to carefully center the target on the finder crosshairs. Proper finder alignment on my scope is super-critical because not only do I need it to find objects in the sky but to accomplish the precision polar alignment since on the Celestron the finder also serves as the polar alignment telescope as well. Once aligned, I will install the batteries in the reticule illuminator LED and place the LED and battery pack in its receptacle on the finder scope. Normally I keep the batteries out of the illuminator since they tend to die quickly if the LED is inadvertently left on, something that a weak design and a weaker memory makes very easy to do. The next job is to set up the power supply battery. This is a simple 12-volt DC automobile battery....
The control of the temperature of the equipment and structure of a spacecraft is important for two main reasons. Outside a relatively narrow temperature range, equipment will usually not operate efficiently or reliably. Secondly, thermal expansion and contraction of materials can cause distortion in the structure. As most equipment onboard a spacecraft was originally designed for use on the Earth and because it is usually easier and cheaper to get equipment developed and tested at room temperature, most spacecraft equipment also needs to be operated at about room temperature. For rechargeable batteries, the temperature can vary between about 0 C and 20 C most electronic equipment operates between about -15 C and 50 C and mechanisms such as gyroscopes and solar array drives operate between about 0 C and 50 C.
Several crucial design elements had already been chosen by 1964. Metal wheels were preferred to track-laying concepts because they consumed less power, were less complex, and were not as sensitive to temperature extremes, among other advantages. Electric motors were chosen as the means of propulsion, but significantly, each wheel would be driven by an individual motor. Initially, it was thought that hydrogen-oxygen fuel cells would be the means of providing electrical power to the motors, but these would ultimately give way to relatively conventional batteries. Vehicle steering would be achieved using two levers instead of a traditional steering wheel. This, too, would eventually be refined considerably. However, in November 1964, NASA Associate Administrator, Dr. Robert Seamans, announced general post-Apollo plans that effectively shelved the ALSS (including MOLAB) until after 1975, in favor of a less ambitious approach. astronauts, or one astronaut with added cargo capability. The...
In LEO, on the other hand, the spacecraft may be in eclipse and thus require battery power for 40 of each orbit. Although the precise duration will depend on orbit inclination, it is fairly regular, and the eclipse cycle results in typically 3000 to 6000 change discharge cycles of the battery per year. This results in the array-power sizing needing to be nearly twice the nominal load requirement (see Section 10.6). In summary LEO operations require a large number of low-depth discharges, whereas in GEO a few deep discharges suffice. This inevitably influences battery type, resulting in the present trend of using nickel-cadmium (Ni-Cd) or silver-zinc (Ag-Zn) cells for LEO operation and nickel-hydrogen (Ni-Hb) cells for GEO operations. Cell cycle life, specific weight (kWh kg) and volume (kWh m3) all influence the acceptability of a particular battery technology. However, work on more exotic materials, for example, LJ-SO2, is continuing 13 and alternative technologies continue to be...
If the starship uses a magnetic ramscoop, a deceleration magsail, or a magnetic cosmic ray deflector, there is another power option. As discussed by Smith (1969), a superconducting solenoid or coil can serve as magnetic-energy storage battery as well as an ion deflection device. Yet another possibility to supply the power needs of a starship's crew is a solar storage battery that could be charged whenever the craft is close to a star. One possibility for such a device is the 'light sail windmill' proposed by Birch (1983). Such a device would consist of hyperthin and superstrong blades, with the blade aspect designed such that solar radiation pressure causes windmill spin-up during a close perihelion pass. (For further discussion of the light-sail windmill, see Matloffs (1985) paper on interstellar arks, Matloff and Ubell (1985), Matloffs (1986) worldship paper, and Birch's (1985) correspondence in Journal of the British Interplanetary Society.)
A prototype LUNOX processing plant was designed and built at the University of Arizona in the mid-1990s. It is a good example of the design considerations that would be appropriate to a robotic proof-of-concept mission. The design includes a rotating table, a solar furnace consisting of two mirrors and a small reactor, and two robotic arms. The electrical energy requirement is limited to powering the onboard computer and robotic motors, and a solar furnace is used for heating. The power needed can be generated by an array of solar cells and stored in a small bank of rechargeable batteries. Figure E.14 shows a side view of the prototype, and Figure E.15 shows a top view. The accurate and fully-operational prototype is a half-scale model, which includes computer-controlled robotics and tracking.
Spacecraft temperatures must be controlled to within close lower and upper limits. These are imposed by the different characteristics of the various components on the spacecraft. Particularly sensitive to temperature extremes are storage batteries, spacecraft propellants, many electronic components, and certain scientific payloads. The allowable limits for electronic components are not necessarily the same for operating and nonoperating conditions (when operating, the additional electric stress often imposes a lower upper temperature limit).
Launch Battery power is used at high discharge rate, and the system operates through the launch environment of shocks and vibration. Transfer orbit Solar array generates limited power. The battery powers the pyro bus loads only. Redundancy management is enabled. Non-operational on-orbit Full power generation, but less then full load. Supports eclipse and battery charging.
The vast majority of spacecraft, this implies the use of battery technology. However, there are other possibilities, although they are rarely used. For example, a fly wheel can be installed as an alternative electrical storage device. While the spacecraft is in sunlight, solar panel power can be supplied to a torque motor to spin a large wheel. When the spacecraft is in darkness, and the primary power source no longer works, the rotational energy in the wheel can be extracted and converted back into electricity.
Broadly considered, the power conditioning subsystem must fulfill three functions on a spacecraft utilizing solar arrays. First, it must control the solar array output in response to changes in load requirements and to changes in array temperature and sun angle, which as we have seen significantly alter the source properties. Second, it must control the battery charge-discharge cycle, supplying the proper charging voltage and current and regulating the average discharge voltage. Finally, the power system must regulate the voltage supplied to the remainder of the spacecraft system to the specified level (within some tolerance), thus protecting the other subsystems from the fluctuations already cited. This last requirement is obviously present even on spacecraft using RTGs, fuel cells, or any other power source. The second requirement may be relevant as well, if the peak loads exceed the steady-state source capability. In most DET systems, a shunt regulator will be connected across the...
The power subsystem must satisfy all of the electric power needs of the robot spacecraft. Engineers commonly use a solar-photovoltaic (solar-cell) system, in combination with rechargeable batteries, to provide a continuous supply of electricity. The spacecraft must also have a well-designed, built-in electric utility grid, which conditions and distributes power to all onboard consumers.
It's much better to use portable lead-acid batteries, either gel cells or deep-cycle boat batteries. Check the battery voltage periodically during use and don't let it get below 12.0. Recharge the battery before storing it. The capacity of a rechargeable battery is rated in ampere-hours (amp-hours, AH), thus Battery capacity in ampere-hours Hours of battery life - --- --- If possible, you should measure the current drawn by your equipment using an ammeter. If you have to guess, a telescope draws about 1 ampere, a dew heater system draws 2 or 3, and an autoguider or laptop computer may draw 2 to 5 amperes. That's enough to run down a commonly available 17-AH battery pack very quickly. In such a situation, a 60-AH deep-cycle battery is worth paying for, even though it isn't cheap. Better yet, put the telescope on one battery, the laptop on another, and the dew heater on a third. This will prevent ground loop problems (see p. 118) and will ensure that a mishap with one piece of equipment...
Mills realized he couldn't build a 1-G trainer in a mere ninety days, but he did feel that his team could build a rugged training vehicle that would closely resemble the LRV using readily available steel tubing, surplus or salvage parts and some clever imagination. Within the limitations of the vehicle he had to build, Mills also wanted Grover to be electrically powered. He was familiar with numerous different types of electrical motors, and he drew on his experiences during World War II to seek out a source for the vehicle's drive motors. After doing some research, Mills settled on the landing gear motor from a B-26 bomber from a military surplus dealer in California This motor had a built-in gear reduction of 45 1 and each cost a mere 12.50. To power the motors, Mills chose four standard off-the-shelf six-volt lead-acid batteries,
Spacecraft storage batteries require particularly close thermal control. The requirements can vary greatly, depending on whether the battery is used at a low charge or discharge rate or at high ones. Often, both heating and cooling are needed to meet the varying conditions. Cooling can be obtained by mounting the battery such that one of its surfaces can radiate into space. As indicated in the example shown in Fig. 7.15, this surface is designed as a radiator with low solar absorptivity and high ambient temperature emissiv-ity. In the case of satellites in equatorial or near-equatorial orbits, preferred mounting positions are the north and south panels of the spacecraft, where the solar radiation incidence and its variation are minimal. External heating is provided in this example by patch heaters. Figure 7.15 Thermal protection of a storage battery on a three-axis stabilized spacecraft.
Twelve-volt hair drier and battery pack. Figure 7.4. Twelve-volt hair drier and battery pack. The practical alternative to dew prevention is dew removal. Several astronomical suppliers provide dew guns. These are merely 12-volt portable hair driers that plug into the cigarette lighter socket of a car or battery pack (Figure 7.4). These are usually significantly less expensive if they are obtained from a camping store as traveling hair dryers.
Among the first reports related to rovers since the announcement of the VSE was Expanding Frontiers with Standard Radioisotope Power Systems, published in January 2005. Written primarily by scientists and engineers at the Jet Propulsion Laboratory, with contribution from NASA Headquarters, this document looked at the power requirements of lunar and Martian rovers for the future. The original Lunar Roving Vehicle employed rather conventional batteries, which were adequate for the length of the Apollo 15, 16 and 17 missions. The power requirements of future lunar and Martian rovers would be much more demanding. Radioisotope Power Systems (RPS) had been used by the United States for space exploration since 1961. RPS generate electrical power by converting the heat released from the nuclear decay of radioactive isotopes into electricity through any one of a number of conversion processes. These RPS were known for their long life, ruggedness, compact size and reliability. The standard RPS...
On the second traverse, the attitude indicator pitch scale fell off, but the needle was still used to estimate pitch attitudes. Incorrect matching of switches caused a loss of rear-wheel power. Correct switch configuration returned the vehicle operation to normal. The crew noted that the forward wheels tended to dig in when attempting to climb slopes without rear-wheel power. The right rear fender extension was knocked off and, thereafter, dust was thrown up from the right rear wheel and covered the crew, the console, and the communications equipment. Mid-way through the second extravehicular traverse, the ampere-hour integrator for battery 1 began indicating about four times the normal battery usage. Because of high-than-desired temperatures on battery 1, a series of procedures were initiated to lower the load. These procedures probably caused the inadvertent removal of drive power from a pair of wheels, thereby losing two odometer inputs and the associated static range, bearing, and...
At the initial power-up, the lunar roving vehicle battery temperatures were higher than predicted 95 degrees F for battery 1 and 110 degrees F for battery 2 compared to the predicted temperatures of 80 degrees F for each. This was partially due to the trans-lunar attitude profile flown, and partially to a bias in the battery temperature meter. Following adequate battery cool-down after the first extravehicular activity, temperatures for the remainder of the lunar surface operations were about as predicted.
At launch, the spacecraft payload had a total mass of 1,400 pounds (636 kg), composed of the 1,087-pound (494-kg) dry spacecraft and 312 pounds (142 kg) of onboard propellant. The scientific instruments included the solar-wind collector arrays, ion concentrator, and solar-wind (ion and electron) monitors. A combined solar-cell array with a nickel-hydrogen storage battery provided up to 254 watts of electric power just after launch.
NASA has been conducting field tests of vehicles and the next generation EVA suits that will be employed when astronauts first return to the Moon. The Science, Crew, Operations and Utility Testbed (SCOUT) was developed by Johnson Space Center to explore advanced technologies that would be employed by future lunar and Martian vehicles in support of missions. This program began as a fuel cell development program, an alternative to using relatively conventional batteries on a robotic rover testbed, but it soon became an effort to develop a fully-fledged rover testbed as a mobile platform. Frank Delgado is the project lead for SCOUT.
The CAT is on the tripod with just a little cussing from me, but it's far from ready to observe anything. Not without power. I return to the car for two 12-volt battery packs, one for the telescope and one for the dew heater that keeps the 11-inch SCT's big corrector lens dry. Luckily, for once, I've remembered to bring power cords for both batteries. Ready yet Not yet.
Finally make absolutely certain that you won't run out of power in the field. Make sure that if your computer manufacturer offers dual batteries or a heavy-duty battery that you buy it. If not, make certain that you can operate near an AC power source or buy an optional DC (cigarette lighter) power adapter. Most standard laptop batteries will not last more than an hour especially if you are running a CD drive with any of your software or if you have a CCD (Meade DSI or LPI) that draws power from your computer.
Depending on how much equipment you are carrying into the field, you may have several different power sources. Many small rechargeable batteries are of the nickel-cadmium type. Remember that to get the best endurance and voltage out of a ni-cad, you need to be a little nasty to it. Make certain that you run all your rechargeable nickel-cadmium batteries down to exhaustion. Remember that dirty or rusty contacts do not transmit electricity so keep them clean periodically. Cold temperatures can also cause voltage loss. To preserve the charge of the batteries, keep them in a warm place as much as possible. Sub-freezing temperatures can cause you as much as a full volt out of the battery's charge. Lead acid batteries in particular need to be kept out of the cold.
When the primary power source is not available, for example, if the solar arrays are in the Earth's shadow, a secondary power source is required. These are usually batteries, although some systems use a combination of solar arrays and fuel cells. Sputnik 1 relied on non-rechargeable batteries for its only power supply, but with improvements in technology, rechargeable batteries are usually used as the secondary power source. The charge and discharge characteristics of the batteries are important on missions with quick discharge and recharge times. For example, a satellite in a low Earth orbit may experience an eclipse nearly 16 times a day. The total eclipsed time is about equivalent to the time spent recharging. The battery therefore needs to be able to be discharge and recharge relatively quickly. The amount the battery discharges between recharges is called the depth of discharge or DOD. Large DODs cause the lifetime of the battery to be short. The battery lifetime is the number of...
Fuel cells Fuel cells have been used in NASA's spacecraft designs since the Gemini missions. On the space shuttles, three fuel cells, each weighing 260 pounds (118 kg) and rated at 10 kW, run everything except for a few battery-powered experiments. The fuel cell intercepts the stream of electrons that flow spontaneously from the reducer (the fuel) to the oxidant, and it diverts the stream for use in an external circuit. The main distinction between a fuel cell and a conventional battery is that the fuel and oxidant are not integral parts of a fuel cell, but instead they are supplied as needed to provide power to an external load, while the waste products are continuously removed. In the case shown in Figure A.11, hydrogen is supplied to the anode, oxygen to the cathode, and water is produced.
Plans are moving forward to refurbish Hubble later in the decade. The telescope will be outfitted with a powerful new camera and ultraviolet spectrometer that will further boost its discovery potential. Once refurbished with new batteries, gyroscopes and other equipment, HST could potentially continue observing up until the 2013 launch of its successor, the James Webb Space Telescope. The HST servicing mission is contingent upon the Space Shuttle's successful return to flight in 2006. Hubble is booked on the manifest of future Shuttle launches after the return to flight demonstration is deemed successful.
Table 10-8 outlines the three steps for estimating spacecraft power requirements. Fust, we prepare an operating power budget by estimating the power required by the payload and the spacecraft subsystems. If the spacecraft has several operating modes that differ in power requirements, we must budget separately for each mode, paying particular attention to peak power needs for each subsystem. The second step is battery sizing, or selecting the battery capacity appropriate to the spacecraft power requirements and battery cycle life. With size established, we can compute the battery's recharge power. The third step is accounting for power-subsystem degradation over the mission life by computing radiation damage to the solar array. Sections 10.4.6 and 11.3 discuss battery recharge power. At the minimnm, the recharge energy must exceed the energy drawn from the battery during discharge by an amount that accounts for the efficiency of the charge-discharge process (typically 80 ). Most...
The counterpart to the LTA is the Hard Upper Torso (HUT), which is made of fiberglass and connects the arm module, glove module, and helmet module. The Primary Life Support System (PLSS) attaches to the back of the HUT. It resembles a backpack and provides the astronaut with oxygen and battery packs. The PLSS also controls the air pressure in the suit as well as the temperature of the oxygen and water that run through the garment to keep the astronaut cool. The HUT removes humidity, odors, and carbon dioxide from the air inside the suit and also carries the communication equipment and a multitude of sensors. A secondary oxygen pack attaches to the bottom of the PLSS for emergency oxygen and other life support functions. On the front of the HUT, astronauts carry a Display and Control Module, which keeps them informed about the status of the PLSS.
This approach provides a highly reliable quick-reaction power source that is nevertheless protected from degradation and requires no maintenance during extended storage. Another quick-reaction, diy storage battery is the thermal battery. In this case, the electrolyte is solid at normal temperature. Ignition of a chemical heater, which melts the electrolyte and results in a fully charged battery, activates the battery. The battery stays active as long as the electrolyte is molten or until it is fully discharged. A more recent development in battery technology is the nickel-hydrogen (Ni-H2) design. This battery differs from other types in that a large amount of free hydrogen is generated as part of a charge discharge cycle. As a result, quite high Most battery chemistries so far developed cannot accept so many chargedischarge cycles thus, for such applications, Ni-Cd batteries have been the system of choice, despite their low energy density. However, even with...
With webcam and laptop ready to go, it's time to take the whole set up into the field. When imaging at home (there's no need to go to a dark site for planetary picture taking), use an extension cord from the house or a garden outlet to provide AC for the computer. Yes, laptops have built-in batteries, but most will poop out in an hour or less. Nothing is more annoying than having the computer battery die just as the good images are starting to roll in.
Despite this failure, unmanned craft clearly offered a cost-effective way for Soviet scientists to continue exploring the Moon. Luna 16 worked perfectly, landing on the Sea of Fertility in September 1970 and drilling 100g (3V20Z) of rock that was returned to Earth over Soviet territory. Another new type of mission was pioneered by Luna 17 in November 1971. After landing in the Sea of Rains region, the probe released an automatic rover, Lunokhod 1. The size of a small car, it was designed to operate under solar power, with rechargeable batteries to see it through the long lunar night. Lunokhod 1 trundled around the surface for 321 days, photographing its landing area and analyzing the soil chemistry.
Resulting modifications of the model will improve the choice. Thermally sensitive subsystems will require a more extensive breakdown into nodes than is needed for those less sensitive. Typically selected as nodes are the main structural elements of the spacecraft, electronic boxes, solar array panels, antennas, rocket motor components, temperature-sensitive components such as storage batteries, propellant tanks, cryogenic subsystems, and scientific instruments. Still others are thermal control devices such as louvers and those using phase-changing materials.
To create the L-1 for the circumlunar flight, the Russians needed to reduce the weight of the Soyuz. They removed the living section, the reserve parachute system, a backup maneuvering system, and some solar battery panels. They added extra jets for reentry control and beefed up the thermal shield. The first unmanned test of the L-1 on a UR-500K was Kosmos 146 on March 10, 1967. It orbited for eight days, and the L-1's engine performed well. The second test on April 8 failed. Two weeks later, disaster struck.
The first version of the flight plan had envisaged the tunnel remaining sealed until in lunar orbit. Aldrin, however, had successfully argued for an inspection of the LM during the translunar coast, since if the rigours of launch had so damaged that vehicle as to render it unusable it would be best to discover this sooner rather than later. However, as a result of the mass limit imposed on the design of the LM, it could accommodate only six chemical storage batteries, which in turn limited the total electrical power supply, with the result that at this point in the flight it would not be feasible to power it up to transmit telemetry to enable Houston to check its systems. Nevertheless, an early entry would enable Aldrin to make a start on chores such as removing and stowing protective covers.
My telescope itself consists of the optical tube, a fork mount that the telescope swings through for storage and the drive base. In 1986, internal batteries were not common. I bought mine from a dealer who specialized in innovations such as these. Roger W. Tuthill of Mountainside, NJ was one of the first to specialize in retrofitting new telescopes with internal batteries. Tuthill devised a means of placing two lead acid batteries inside the drive housing of a Celestron telescope allowing it to be taken away from any source of power for up to eight hours at a time. A DC voltage regulator and an AC inverter turn the battery power into household current for the standard telescope drive motor. Today, all the major manufacturers offer this feature standard, but this was a revolution in telescope portability in 1986. Batteries need to be cared for just as telescopes do. Nickel-cadmium batteries in particular need to be looked after in a careful way. Believe it or not, for a ni-cad to work...
Space probes landing on Mars or other planets often need to survive long, cold nights during which there is no light for the solar arrays to use to make electricity. To keep sufficiently warm without draining the rechargeable batteries, these probes can be equipped with Radio-isotope Heater Units (RHUs).
Shunt mode regulates the bus voltage by using a shunt dissipator. In this mode, the batteries are fully charged and the solar array power generation exceeds the spacecraft's needs, so the excess current from the solar array is shunted. This mode is established when the shunt drive voltage signal is greater than 2.5 V d.c. and the battery charge currents are not responsive to the shunt drive voltage. Battery charge control mode regulates the bus voltage using the battery chargers as linear shunting circuits. In this mode, the batteries are charged and the spacecraft loads are met by the solar array. If the solar array power capability is only slightly above the system load, the battery charge current must be limited. This mode is established when the shunt drive voltage is 1.0 to 2.5 V d.c. and the battery charge current is linearly responsive to the shunt drive voltage and is between 0 and 3.6 A. Discharge mode regulates the bus by the battery discharge converter. In this mode, solar...
Despite their small screen size, PDAs offer much to the visual observer. They're eminently portable, comfortable to hold in the hand for long periods of time, and have a pretty long battery life. We've seen how astronomical software can be used in the field to plan observations and produce observing blanks and how graphics software is capable of translating stylus strokes on their touchscreens into sound astronomical observational sketches. Button mapping is a useful tool in which individual applications can be assigned to any of the PDA's physical buttons, allowing programs to be accessed quickly and viewed at the user's convenience. For example, buttons on the PDA may be assigned to begin screen capture, planetarium, and drawing programs.
This is often caused by a loose connection somewhere in the power system inadequate battery voltage or electrical noise on the power line, such as poor filtering of an AC-operated power supply. If using internal batteries, check the battery contacts and try using an external power supply. Rechargeable lead-acid batteries are the gold standard for power supplies they produce very clean, well regulated DC. Sometimes, however, runaway is caused by a loose connection. On the LX200, check the declination cable. Check also for electrical problems, such as inadequate battery voltage, loose connections, or even a metal cover plate accidentally touching connections inside.
DIY Battery Repair
You can now recondition your old batteries at home and bring them back to 100 percent of their working condition. This guide will enable you to revive All NiCd batteries regardless of brand and battery volt. It will give you the required information on how to re-energize and revive your NiCd batteries through the RVD process, charging method and charging guidelines.