Monday, November 30, 2015

Evolution of Video Game Controller Design

Video games, like most other forms of entertainment and technology, have immensely improved throughout their relatively recent history, generally taking what has worked well in the past and enhancing it for the next generation. One of the major improvements is that of graphics, which thirty years ago were very basic at 8-bits, while today can be presented in 1080p or 4K. Advances in hardware, which for the most part can be observed by looking at only the gaming controllers of different consoles, supported the gradual software improvements that have occurred during this time.

For console gaming, the controller is the primary interface between the player and the virtual world. While there is also a screen, either that of a television or on the console in the case of portables, along with the emission of sound, the controller is the one thing that gives the player control to interact with the game. Something else that is important to note is that there really isn’t a standard controller with which all games and consoles can interact, and there is no set of guidelines that are focused specifically on the construction of a controller. Despite this, the controller has remained very similar with many different companies behind its design throughout the history of gaming, and current companies have made use of all of the past successes to design products that allow for ergonomic use better than ever before.

Different supercomputers and arcade games are considered the First Generation of video games, along with the first home system, the Magnavox Odyssey, which was released in 1972. The Second Generation made even more use of home video game entertainment with several different consoles, but the most popular during this time was the Atari 2600, which was released in 1977. The 2600 controllers really bear little resemblance to most other video game controllers, since they were either a large joystick with a red button or a twistable circular paddle, also with a red button. The design for both of these was adopted from the different arcade games that were ported to play on the 2600.

Atari 2600 Joystick

Atari 2600 Paddle Controller

The Third and Fourth Generations of video games spanned the mid-Eighties to the mid-Nineties and were dominated by Nintendo, who faced competition from Sega. The controllers that were made for the Super Nintendo and Sega Genesis, the leading consoles during the Fourth Generation, are completely different from that of the Atari 2600. Their primary construction included a gamepad, which on the top surface placed several of the primary buttons on the right side, a directional pad meant for movement, or d-pad, on the left side, and start and select buttons in the center, as well as R and L shoulder buttons on the back surface of the Super Nintendo controller. While controllers during this time were smaller, lighter, and less refined than they are today, these models ultimately served as the template for what has become the modern video game controller, since all of these features have been retained in newer models.

Super Nintendo Controller

Sega Genesis Controller

The Fifth Generation, occurring in the mid- to late-Nineties, reintroduced the joystick to the controller in the form of an analog stick, which was designed to be controlled by the player’s thumbs. This inclusion is likely related to the fact that graphics and software capabilities had improved enough around this time to make the games 3-dimensional. Interacting with a 2-dimensional game, which traditionally were side-scrolling, really didn’t require more than buttons that indicated the direction in which the player wanted the playable character to go. However, in the virtual third dimension, there is an entirely new axis of gameplay introduced, which requires the use of a gesture interface that covers 360 degrees of movement. The Nintendo 64, the follow-up to the Super Nintendo, placed the analog stick right in the middle of the top surface of the controller. While this system is often exalted as one of the best ever, there are some significant issues with the layout of the controller. A huge part of this is that it was designed with three appendages meant for the hand to hold, which can be problematic because it creates somewhat of an awkward grip when a player grips it with both hands. However, this layout really isn’t evident as a vestige in modern Nintendo controllers, mainly because the company has taken a more unique approach, greatly relying on certain inputs such as motion control.

Nintendo 64 Controller

During the Fifth Generation in 1995, Sony released the PlayStation, which introduced a controller that has a layout virtually identical to the majority of controllers used today. This kept the primary buttons on the right side and the d-pad on the left, but was instrumental in introducing a second analog stick, having one placed just to the left and one to the right of the center of the controller. Having two analog sticks is incredibly important for many games, since it allows the player to use one for moving the playable character and the other for controlling the character’s field of vision.

Sony PlayStation Controller

Throughout the years, there have been several other types of controllers that were adapted to be used for specific games. These enhance the player’s interaction with the game, but they are limited to a particular game or genre in which it is still applicable. An example of this is a light gun, which generally works with a sensor bar to make it appear that the player is actually shooting the enemies in a shooter game. Another great example is that of a racing wheel and pedal, which gives players control in racing games in a manner comparable to driving an actual car.

Gaming is currently in its Eighth Generation and is dominated entirely by three companies: Microsoft, creator of the Xbox One, Sony, creator of the PlayStation 4, and Nintendo, who are currently selling the Wii U. All of these use wireless controllers, an important innovation that has been utilized in the past several generations. While the Wii U controller is completely unique, that of the Xbox One and PlayStation 4 are very similar to one another, appearing much like the original PlayStation controller, with small upgrades in shape that make them very comfortable for the player to hold.

Microsoft Xbox One Controller
The controller's shape and button design make it ergonomically sound.

While video game hardware generally adheres to a certain set of principles in construction and presentation, there really aren’t specific guidelines that controls it. Conformity to different aspects of video games and their technology have successfully been managed over time by the competition that has existed between the few companies that have been able to maintain market share in the video game industry. This has encouraged similar technology between different companies, since they each want to have the best product, which leads to the repurposing of other’s ideas.

The idea of generations of video games is also supported by this idea that immense competition between large companies drives the industry. The Atari 2600, while being introduced in 1977, was discontinued in 1991, meaning that it was mass-produced until the fourth generation was introduced, which exceeded it greatly in both hardware and software. This console longevity is something that today would likely not be possible, since the step to the next generation allows for an immense improvement to all qualities of a gaming console. This is simply related to the advancement of computer technology throughout time, and allows each company to make enhancements of memory, storage, and graphics, among others. This encourages companies to release new consoles after several years, once they have sold a large amount of consoles and games for the previous generation. The different active first-party video game companies, or those that make consoles, generally release their new consoles at the same time, and the three recently released home consoles of the eighth generation became available in close proximity to each other in 2012-2013. While controllers really aren’t the primary aspects of consoles that are significantly improved in each generation, it is still advantageous for each console-developing company to produce a controller that encourages and enhances gameplay.

With companies updating their primary selling console every few years and the different choices that are available for consumers, it is ideal to maintain some level of interoperability between different consoles with controllers. This raises the question of whether or not there should be a standard controller that works for all consoles, which would likely be answered simply with no. Since video game companies have made use of the different design components that have been common throughout the technology’s history, they rarely introduce something that seems foreign to a player. Additionally, Microsoft and Sony have been designing their controllers in a manner that encourages the player to grip the controller with both hands, while making use of only the thumbs and pointer fingers for gameplay interaction. Nintendo, while having a much different controller for the Wii U, also designs its controllers so that the player can interact with games in this way. Even though they can only be used with a specific console, controllers are still simple for anyone to use, regardless of which consoles they are used to playing.

Search the ANSI Webstore for standards that relate to video game programming and hardware.

Monday, November 23, 2015

Advantages of Fluid Power

Fluid power is harnessed through either hydraulics or pneumatics technologies, which use a liquid or gas, respectively, to transmit power from one location to another. These have their basis in Pascal’s Law, which states that when there is an increase in pressure at any point in a confined fluid, there is an equal increase at every other point in the container. Hydraulics and pneumatics make use of this concept to multiply forces and move power throughout the system. Even though it is not as popular as electromechanical energy, fluid power has many distinct advantages that make it ideal for different services. Additionally, there are many unique qualities to fluid power based machines, so it is essential to maintain the proper guidelines while creating them.

Electricity, despite being one of the main ways that we transmit energy throughout the world, can be incredibly hazardous. According to OSHA, 8.4 percent of all construction fatalities in the United States in 2014 were the result of electrocution, and it is considered one of construction’s “Fatal Four”. Certain environments, such as working during a light rainstorm, can contribute even more to these hazards, and sometimes just a spark is needed to set off a disastrous event. While there are many techniques to mitigate electric shock and related hazards such as burn, machines that use fluid as the source of power avoid this life-threatening issue almost entirely.

Another major advantage of fluid power is that pressure can remain constant without having to apply significant amounts of additional energy to the system. Hydraulic or pneumatic pumps are easier and more cost effective for tasks that require both pressure and position control. Compare this to an electric motor, which requires constant torque to drive and can lead to overheating if it is not limited by the control system. The high levels of power that can be achieved through relatively simple means in hydraulics makes the technology ideal for certain types of heavy equipment, such as cranes, lifts, bulldozers, and diggers.

Hydraulic and pneumatic systems contain many unique components that together coordinate the movement of the fluid throughout the circuit to transfer power. ISO 5598:2008: Fluid power systems and components - Vocabulary establishes the terminology associated with all aspects of fluid power, spanning from construction of machines to their use, which is very helpful for those not well versed in the subject.

Properly marking the different components in fluid power circuits is essential for the functioning of these machines in an efficient and safe manner. ISO 1219-1:2012: Fluid power systems and components - Graphical symbols and circuit diagrams - Part 1: Graphical symbols for conventional use and data-processing applications provides specifications for graphic markings meant to label the fluid power system components at their de-energized, or at rest, position.

While fluid power lacks some of the hazards that are common with electrical machinery, it still maintains many of the same machinery-related opportunities for workers to come under harm and has some unique associated hazards. For example, it is necessary to maintain proper pressure in fluid power machinery to prevent it from behaving erratically and bringing harm to the machine’s operator. The Hydraulic and Pneumatic Fluid Power Safety Package accommodates many of these issues by including different standards that together provide guidelines for hydraulics, pneumatics, and machines in general, dealing with their design, construction, and modification.   

The National Fluid Power Association (NFPA) is an ANSI-accredited standards developing organization that publishes standards relating to both hydraulics and pneumatics technologies.

Friday, November 20, 2015

Managing Traditional Chinese Medicine in the Western World

To some, Traditional Chinese Medicine (TCM) is merely pseudoscience, while others embrace the benefits it gives them that Western medicine cannot provide. Even though the effectiveness of the different practices of TCM have been greatly debated, millions of Westerners still use them every year, and the amount of patients for different TCM have been rapidly increasing since the late 1990s, with the number of visits to acupuncturists in the United States tripling between 1997 and 2007. With many people making use of these services and clearly benefitting from them in some way, it is essential that they be maintained so that they do not bring unwanted harm or interfere with the effectiveness of Western medicine. An example of this is through ISO 18664:2015: Traditional Chinese Medicine - Determination of heavy metals in herbal medicines used in Traditional Chinese Medicine, which can help to ensure that the herbal medicines that people take for different ailments do not bring them harm.

Traditional Chinese Medicine is really an umbrella term referring to several different practices that uphold a similar set of principles for healing the human body. All of TCM revolves around the idea of Qi (pronounced chee), a life energy that flows through invisible channels of the body known as meridians. Many meridians follow the major veins and arteries in the human body, and regulating the flow of Qi throughout these areas is a major tenet for understanding health in the body. Another essential component of these practices is yin and yang, the conditions in the body that are both opposite and interdependent. Practitioners believe that a harmonizing balance of yin and yang is essential for health, and each organ has a different balance of these qualities. These different concepts are supported by the belief that the human body is a miniature version of the larger, surrounding universe, in which the elements fire, earth, wood, metal, and water explain biological functions. Practitioners of Chinese herbal medicine, acupuncture, and tai chi follow all of these convictions.

Traditional Chinese Medicine has a very long history and is a very long-lasting form of medicine, only being predated by practices of Ancient Egypt and Ancient Babylon. Originating in the late BC, a great deal of TCM fruited spiritually or religiously. Due to the widespread adoption of Confucian techniques, children took care of their parents because it was considered a personal responsibility to care for one’s family members. A Taoist concept that played an important part in early Chinese medicine was that of longevity, since many emperors strove to ingest herbs that would make them live forever. An example of this is Emperor Lingdi, ruler in 168-189 AD during the Han Dynasty, who invited Buddhist monks of another Taoist sect from India in the hope that they could make him immortal. These regal immortality elixirs became the basis for Chinese prescriptions, and several prominent physicians rose throughout the Han Dynasty. Since this time, TCM has developed greatly, making use of medical texts and education that established it as the standard form of medicine in the nation. During the majority of its history, TCM remained isolated in China until the country was opened in 1972, which has led to its introduction in the Western world.

The long lasting nature of TCM is a testament to the services that it can provide, since its subgroups are unique when compared to those that we get from advanced medicine. Medicine is something that has evolved so greatly since the dawn of civilization, even having advancements today that have displaced those from just several years ago. Ancient forms of medicine made use of materials and substances that were in the immediate reach of the people in the society in which they originated. Once stronger trade routes and advancements in science were established, remedies more effective that had a greater basis in science replaced the majority of these materials. For example, the Ancient Egyptians used honey for dressing wounds, which is now known to actually have antibacterial purposes due to substantial amounts of hydrogen peroxide. Today, this is solved by many different treatments that are more effective than honey while accommodating the same need. However, many forms of TCM provide people with something that they do not believe they can get somewhere else. For example, acupuncture provides people with a cure for different ailments in a much different manner than ingesting pills.

Today, TCM has drawn upon Western medicine for improvements to its methods. ISO 18664:2015 serves to incorporate scientific understanding into the application of Chinese herbal remedies for those who choose to use them by specifying determination methods of lead, arsenic, cadmium, and mercury content in the herbs. It is not intended to set maximum limits on these materials, but simply to provide standardized testing methods for risk assessment on their consumption. It identifies several different methods for determining these metals in the herbal remedies, along with their specific strengths and weaknesses when compared with one another. This also serves as a guide to compare any amounts uncovered with those allowed by a specific nation.

In addition to ensuring that herbal remedies are safe, people who wish to make use of TCM for its healing properties should always make sure to seek a professional for something like acupuncture so that they can be properly cured. 

Wednesday, November 18, 2015

Range Anxiety in Electric Vehicles

According to a Consumer Reports Car Brand Perception Survey, 77 percent of U.S. adults do not believe that an electric car could meet their current driving needs. This fear originates from both the lack of significant travel distance on a single charge of an electric car and the lack of charging stations in less densely populated areas. This creates a disparity between public perception and reality in some way, since a study conducted by two Columbia doctoral students concluded that 95 percent of all driving needs of U.S. citizens could be met by electric vehicles. However, this study, while taking in a large amount of data, does not seek to comprehend how this public perception has formed and how to remedy it successfully. If current electric cars were to be used by most people for their driving needs, it would be a necessity to install new charging stations. Additionally, other methods could be used to charge the cars, such as roads that send electricity into the cars’ batteries as they travel.

In the study, “driving needs”, refers to the daily travels of an individual, specifically during a work commute. The evidence indicates that 95 percent of single trips that drivers make involve traveling less than 50 miles each way. This raw data demonstrates that the majority of trips that drivers take in automobiles are often very short, but to claim that this proves that electric cars could satisfy the needs of all drivers at this time is somewhat of a stretch. If this were true, people would only be able to drive short distances (which they often do), but they would not even have the possibility of traveling somewhere far away. In our prior post on electric cars, we discussed how internal combustion engine automobiles gave consumers the opportunity to travel long distances, which made them much more desirable than electric cars. Technologically it would be a bit of a step backwards if cars could only travel distances comparable to those in the early Twentieth Century.

Simply stating that drivers do not actually travel long distances, does not end the problem of range anxiety. According to a survey by Chapman University, the five greatest American fears in order are walking alone at night, being the victim of identity theft, safety on the internet, being the victim of a random shooting, and public speaking. While there is some variation in the outcomes of these different fears coming to reality, they ultimately are based off the fear of the unknown. People are truly terrified of what they do not know, and the result is to make preparative efforts to manage any kind of risk that we might be exposed to. In the case of automobiles, this involves many different safety guidelines to reduce injuries in case an accident occurs. Additionally, drivers tend to keep enough gasoline in their car to ensure that they do not run out before they reach a gas station, something that is supported by the capacity of a car’s gas tank. Ideally, to follow this same trend with electric cars, there should be either sufficient battery to allow people to travel long distances on a single charge enough places for drivers to charge their cars.

Having charging stations at both the homes and the destinations of the electric automobile drivers does not address the issue of long distance travel. As a solution to this, in late 2015 the U.K. will be testing out roads that charge electric cars as they go. This will be done through closed trials, in which each vehicle will be fitted with a wireless device, and special equipment will be installed beneath the roads to replicate motorway conditions. Buried electric cables will generate electric fields that will be picked up by a coil inside the device and converted into electricity, continuously charging the automobile as is it travels along the road. While this is simply an eighteen-month test, it also poses questions about how exactly these charging roads could be introduced. For example, what would their costs be, and what would this mean for old roads that will not be able to upgrade?

Another issue that could be raised with these charging roads is concerns with safety. The Car Brand Perception Survey also uncovered that 42 percent of drivers are worried that electric cars might lead to home fire damage while they charge overnight. If home charging is an issue for people, it might be hard to imagine them being perfectly fine with streets constantly charging their cars as they drive them. However, the possibility for fire to occur will likely be observed during the testing process. At the same time, the fear of an electrical fire from an unmonitored charging electric automobile could derive from the fear of not knowing much about the technology. Charging roads could either contribute to or put an end to this concern, since drivers could fear the constant charging of their car battery or feel at ease knowing that they can keep an eye on the charging process. Ultimately, any understanding of charging roads that we possess right now is riddled with speculation, so we will have to wait eighteen months to gain some knowledge on this technology and how it could potentially be used throughout the world.

Standards for electric vehicles are available on the ANSI Webstore.

Storing Electricity Produced by Solar Energy

There are many standards for solar energy on the ANSI Webstore, ranging from topics in equipment and testing to terminology of solar concepts. The solar industry is currently undergoing significant growth, with a solar photovoltaic system being installed every four minutes in the United States. There are many challenges that exist with trying to implement solar as a major source of electricity generation for utility companies, such as raising the efficiency of solar arrays, but one major technological goal that needs to be achieved for its widespread use is that of storage.

As implied by its name, solar energy can only be absorbed by photovoltaic cells during the daytime when there is appropriate sunlight. As of now, this is not too much of a problem because solar is only a fraction of the total electricity that is generated in the world, either being completely used on-site or sold back to the utility if it completely powers the location where the solar array is placed. However, if solar were to become more widespread, possibly being owned by a utility, there would be a great deal of excess electricity generated throughout the day that could not be used at night unless it were properly stored. This is not a problem with electricity generation with methane or coal, since either one of those substances can be burned at any time to meet the needs of the users. Storing excess solar-generated energy likely requires the use of batteries, which would alter the economics of electricity.

The main batteries that are used to store electricity are either generally composed of lithium ion or nickel metal hydride. These have different advantages and disadvantages when compared to each other, with nickel batteries being much heavier and lithium ion batteries having the potential to catch fire, but they generally hold a similar capacity. The major issue with these batteries and storing large amounts of electricity is that the technology is just not quite there yet to hold the quantities that would be of use for the vast majority of houses at competitive pricing. However, there is a great deal of research and development going into enhancing this with new advances constantly being reported, such as the US Department of Energy doubling lithium ion capacity with the addition of spongy silicon.

Smaller lithium ion batteries are currently used to power devices such as laptops and cell phones

Storage of grid electricity must consider the cost of the batteries. In 2014, the price of a lithium ion battery was between $310 and $400 per kilowatt-hour (kWh), costing about $0.33 to store one kWh. If this amount does not seem like a lot, compare it to the cost of electricity, which on average in the United States is $0.12/kWh. With batteries at these high costs, it is difficult to accept that using them to store energy would be a better method than just letting the comparably inexpensive electricity go to waste. However, these costs have reduced significantly in the past ten years and are due to decrease even more in the future, so this one issue will likely be solved soon.

An alternative for storing the electricity that is generated through solar panels is with the use of compressed air. This method uses electricity to compress air. Using a motor generator and a compressor expander, which can later be used to either cool or heat buildings. Additionally, the air and heat can be used to create electricity for later use. This method currently costs similar amounts as the current battery technologies.

Whichever method is used to store electricity, it is not likely that the traditional electrical grid could support it efficiently. Instead, a smart grid, which allows for sensing along transmission lines and two-way communication between a utility and its customers, would be ideal for managing all of the electricity brought in from a solar array, whether it is instantly spread throughout the grid for usage or stored for later use. This could be properly managed throughout the grid, providing users with the proper amounts of electricity while not letting any of it go to waste. Smart grid technology, just like that of the batteries, is likely to continue to improve in the upcoming years until it can become a reality. Both smart grid and solar power have set many challenging but attainable goals.

Tuesday, November 17, 2015

Assistive Device Standards for Wheelchairs

Do you know RESNA, Rehabilitation Engineering & Assistive Technology Society of North America? RESNA members promote the exchange of ideas and information for the advancement of assistive technology.

RESNA develops standards for assistive devices in the following areas: wheelchairs (including scooters), wheelchairs and transportation, wheelchair seating, support surfaces, vision and hearing impairments, adaptive sports equipment. A long list of standards covering these technologies is on the RESNA website. Here we have the standards with accompanying descriptions and links to download them.

ISO 7176-1:2014 Wheelchairs - Part 1: Determination of static stability
ISO 7176-1:2014 specifies test methods for determining the static stability of wheelchairs. It is applicable to manual and electrically powered wheelchairs, including scooters, with a maximum speed not greater than 15 km/h, intended to provide indoor and/or outdoor mobility for one disabled person whose mass is within the range represented by ISO 7176-11.
For active stability-controlled wheelchairs, ISO 7176-1:2014 applies to the device in a stable, parked state.
ISO 7176-1:2014 provides a method for the measurement of the tipping angles (either wheelchair tipping angle or anti-tip device tipping angle), but this method is not applicable to wheelchairs with lateral anti-tip devices and does not consider sliding on the ground.
ISO 7176-1:2014 also includes requirements for test reports and information disclosure.

ISO 7176-2:2001 Wheelchairs -- Part 2: Determination of dynamic stability of electric wheelchairs
This part of ISO 7176 specifies test methods for determining the dynamic stability of electrically powered wheelchairs.
This part of ISO 7176 is applicable to electrically powered wheelchairs including scooters with a maximum nominal speed not exceeding 15 km/h, intended to carry one person.

ISO 7176-3:2012 Wheelchairs - Part 3: Determination of effectiveness of brakes
ISO 7176-3:2012 specifies test methods for the measurement of the effectiveness of brakes of manual wheelchairs and electrically powered wheelchairs, including scooters, intended to carry one person, with a maximum speed not exceeding 15 km/h. It also specifies disclosure requirements for the manufacturer.

ISO 7176-4:2008 Wheelchairs - Part 4: Energy consumption of electric wheelchairs and scooters for determination of theoretical distance range
ISO 7176-4:2008 specifies methods for determining theoretical distance range of electrically powered wheelchairs, including scooters, using measurements of energy consumed while driving and the nominal energy capacity of the wheelchair's battery set. It is applicable to electrically powered wheelchairs with a maximum nominal speed no greater than 15 km/h, intended to provide indoor and/or outdoor mobility for one disabled person whose mass is within the range represented by ISO 7176-11. ISO 7176-4:2008 also includes requirements for test reports and information disclosure.

ISO 7176-5:2008 Wheelchairs - Part 5: Determination of dimensions, mass and manoeuvring space
ISO 7176-5:2007 specifies methods for the determination of wheelchair dimensions and mass.
This includes specific methods for the determination of outside dimensions when the wheelchair is occupied by a reference occupant and the required manoeuvring space needed for wheelchair manoeuvres commonly carried out in daily life.
ISO 7176-5:2007 specifies requirements for the disclosure of the dimensions and masses and contains five informative annexes.
Annex A specifies methods for the determination of technical dimensions that can be important to the performance of the wheelchair.
Annex B provides detailed information about pivot width and reversing width.
Annex C provides detailed information about the turning diameter.
Annex D provides details on determining the wheelchair longitudinal axis and wheelchair centre-point.
Annex E provides technical guidelines and interpretation for many of the measurements specified to facilitate improved understanding, design and construction of wheelchairs.
ISO 7176-5:2007 is applicable to manual wheelchairs and electrically powered wheelchairs (including scooters).

ISO 7176-6:2001 Wheelchairs - Part 6: Determination of maximum speed, acceleration and deceleration of electric wheelchairs
This part of ISO 7176 specifies test methods for determining the maximum speed, acceleration and deceleration of electrically powered wheelchairs, including scooters, intended to carry one person, with a maximum nominal speed not exceeding 15 km/h (4,167 m/s).

ISO 7176-7:1998 Wheelchairs -- Part 7: Measurement of seating and wheel dimensions
This part of ISO 7176 specifies a method for measuring the seating and wheel dimensions of wheelchairs.
It is applicable to wheelchairs and vehicles intended to provide indoor and outdoor mobility at speed up to 15 km/h for people with disabilities whose mass does not exceed 120 kg, including the following classifications from ISO 9999:1992:
  • Electric motor-driven wheelchairs with manual steering 12 21 24
  • Electric motor-driven wheelchairs with power steering 12 21 27
  • Powered attendant-controlled wheelchairs 12 21 21
  • Manual attendant-controlled wheelchairs 12 21 03
  • Bimanual rear-wheel-driven wheelchairs 12 21 06
  • Bimanual front-wheel-driven wheelchairs 12 21 09
  • Bimanual lever-driven wheelchairs 12 21 12
  • Single-side-driven nonpowered wheelchairs driven by one arm or one leg 12 21 15
  • Foot-propelled wheelchairs 12 21 18

It does not apply to wheelchairs with a seat width of less than 212 mm.
This part of ISO 7176 does not specify nominal seating and wheel dimensions for wheelchairs.

ISO 7176-8:2014 Wheelchairs - Part 8: Requirements and test methods for static, impact and fatigue strengths

ISO 7176-9:2009 Wheelchairs - Part 9: Climatic tests for electric wheelchairs
ISO 7176-9:2009 specifies requirements and test methods to determine the effects of rain, dust, condensation and the effects of changes of temperature on the basic functioning of electrically powered wheelchairs, including scooters, intended to carry one person, with a maximum speed not exceeding 15 km/h.
ISO 7176-9:2009 does not include requirements for resistance to corrosion.

ISO 7176-10:2008 Wheelchairs - Part 10: Determination of obstacle-climbing ability of electrically powered wheelchairs
ISO 7176-10:2008 specifies test methods for determining the ability to climb and descend obstacles of electrically powered wheelchairs, including scooters, intended to carry one person, with a maximum nominal speed not exceeding 15 km/h.

ISO 7176-11:2012 Wheelchairs - Part 11: Test dummies
ISO 7176-11:2012 specifies requirements for test dummies of any mass greater than or equal to 25 kg, to be used in the evaluation of wheelchairs. ISO 7176-11:2012 provides formulae that specify the location of the overall centre of mass of test dummies, the masses of the segments that comprise the test dummies and the locations of pivots that connect the segments. It also specifies the characteristics of loading pads that support the segments.
ISO 7176-11:2012 is intended to enable the construction of test dummies that will produce comparable results for stability, performance and durability testing of manual wheelchairs and electrically powered wheelchairs, including scooters.
ISO 7176-11:2012 also includes informative tables of mass and locations of centre of mass, which are derived from the formulae, corresponding to example test dummy masses up to 300 kg in 25 kg increments.

ISO 7176-13:1989 Wheelchairs -- Part 13: Determination of coefficient of friction of test surfaces
The test method consists in drawing a given block with definite speed over the test surface of in general rough structure. The bottom side of the block is covered with a layer of standard rubber to get comparable results.

ISO 7176-14:2008 Wheelchairs - Part 14: Power and control systems for electrically powered wheelchairs and scooters - Requirements and test methods
ISO 7176-14:2008 specifies requirements and associated test methods for the power and control systems of electrically powered wheelchairs and scooters. It sets safety and performance requirements that apply during normal use and some conditions of abuse and failure. It also specifies methods of measurement of the forces necessary to operate controls and sets limits on the forces needed for some operations.
ISO 7176-14:2008 is applicable to electrically powered wheelchairs and scooters with a maximum speed no greater than 15 km/h intended to provide indoor and/or outdoor mobility for one disabled person whose mass lies in the range specified in ISO 7176-11.

ISO 7176-15:1996 Wheelchairs -- Part 15: Requirements for information disclosure, documentation and labelling
Specifies the information, documentation and labelling to be provided with a wheelchair at the supply by the manufacturer.

ISO 7176-16:2012 Wheelchairs - Part 16: Resistance to ignition of postural support devices
ISO 7176-16:2012 specifies requirements and test methods to assess the resistance to ignition by match flame equivalent of all postural support devices that are supplied to be part of a wheelchair or its seating system.
ISO 7176-16:2012 only determines the resistance to ignition of the devices tested and not the ignitability of the complete wheelchair.
ISO 7176-16:2012 allows for the separate testing of inferior/superior supports (e.g. arm supports), which are usually used in the horizontal plane, and anterior/posterior/lateral/medial supports (e.g. thoracic harnesses, calf panels), which are usually used in the vertical plane.

ISO 7176-19:2008 Wheelchairs - Part 19: Wheeled mobility devices for use as seats in motor vehicles
ISO 7176-19:2008 applies to all manual and powered wheelchairs, including scooters, which, in addition to their primary function as wheeled mobility devices, are also likely to be used as forward-facing seats in motor vehicles by children and adults with a body mass equal to or greater than 22 kg. ISO 7176-19:2008 specifies wheelchair design requirements, performance requirements and associated test methods, and requirements for wheelchair labelling, presale literature, user instructions and user warnings. It applies to complete wheelchairs, including a base frame and seating system, as well as to wheelchairs equipped with add-on adaptive components designed to facilitate compliance with one or more of the requirements.

ISO 7176-21:2009 Wheelchairs - Part 21: Requirements and test methods for electromagnetic compatibility of electrically powered wheelchairs and scooters, and battery chargers
ISO 7176-21:2009 specifies requirements and test methods for electromagnetic emissions and for electromagnetic immunity of electrically powered wheelchairs and scooters with a maximum speed of not more than 15 km/h intended for indoor and/or outdoor use by people with disabilities. It is also applicable to manual wheelchairs with an add-on power kit. It is not applicable to vehicles designed to carry more than one person.
ISO 7176-21:2009 also specifies requirements and test methods for the electromagnetic compatibility of battery chargers intended for use with electrically powered wheelchairs and scooters.

ISO 7176-22:2014 Wheelchairs - Part 22: Set-up procedures
ISO 7176-22:2014 specifies a set-up procedure to be used as a part of the preparation of adjustable wheelchairs for testing. This procedure takes the manufacturer's instructions into account.
ISO 7176-22:2014 is applicable to manual wheelchairs and electric wheelchairs (including scooters) intended to provide indoor and/or outdoor mobility.

ISO 7176-25:2013 Wheelchairs - Part 25: Batteries and chargers for powered wheelchairs
ISO 7176-25:2013 specifies requirements and test methods for batteries and battery chargers intended for use with electrically powered wheelchairs. It is applicable to lead acid batteries and chargers intended for use with them. Requirements for chargers are applicable to those with a rated input voltage not greater than 250 V a.c. and a nominal output voltage not greater than 36 V.

ISO 7176-26:2007 Wheelchairs - Part 26: Vocabulary
ISO 7176-26:2007 specifies a vocabulary consisting of terms and definitions used in the field of manual and electrically powered wheelchairs (including scooters) and associated seating systems.
ISO 7176-26:2007 includes, but is not limited to, the preferred terms used in two or more ISO standards of the ISO 7176, ISO 10542 and ISO 16840 series, but does not include terms considered to be adequately defined in everyday English.

ISO 7176-28:2012 Wheelchairs - Part 28: Requirements and test methods for stair-climbing devices
ISO 7176-28:2012 is applicable to stair-climbing chairs and stair-climbing wheelchair carriers where the stair-climbing device climbs backwards up the stairs, with the occupant facing downstairs, and climbs forwards down the stairs with the occupant also facing downstairs.
ISO 7176-28:2012 is applicable to stair-climbing devices which are intended for the transport of adults and those intended for the transport of children. It is not applicable to stair-climbing devices which are intended to be operated by children as operating occupants or assistants.
ISO 7176-28:2012 specifies requirements and test methods for electrically powered stair-climbing devices. It is not applicable to manually powered stair-climbing devices.
ISO 7176-28:2012 specifies tests to demonstrate the stair-climbing device's ability to perform safely on stairs with a pitch of 35°, or higher if declared by the manufacturer. It also includes ergonomic, labelling and disclosure requirements.

ISO 16840-1:2006 Wheelchair seating - Part 1: Vocabulary, reference axis convention and measures for body segments, posture and postural support surfaces
ISO 16840-1:2006 applies to seating intended to provide postural support within a wheelchair. It specifies:
  • a global coordinate system that permits the determination and recording of a person's posture while seated in a wheelchair;
  • the standard terms and definitions for use in describing both the posture and the anthropometrics of a person seated in a wheelchair;
  • the terms and definitions for describing the dimensions, location and orientation of seating support surfaces, which together comprise the body support system.

ISO 16840-1:2006 does not specify any methods for use in measuring a person's seated posture, nor does it define terms for dynamic physiological movements (such as flexion or extension).
ISO 16840-1:2006 might be applicable to seating other than that intended to be used within a wheelchair.

ISO 16840-2:2007 Wheelchair seating - Part 2: Determination of physical and mechanical characteristics of devices intended to manage tissue integrity - Seat cushions
ISO 16840-2:2007 specifies apparatus, test methods and disclosure requirements for wheelchair seat cushions intended to maintain tissue integrity and prevent tissue trauma. It does not include test methods or requirements for determining the fire resistance of cushions and addresses neither the interface pressure distributing characteristics of seat cushions nor the heat and water vapour dissipation characteristics of seat cushions.
ISO 16840-2:2007 can also be applicable to tissue integrity management devices used as other support systems, as well as to cushions used in situations other than a wheelchair.

ISO 16840-3:2014 Wheelchair seating - Part 3: Determination of static, impact and repetitive load strengths for postural support devices
ISO 16840-3:2014 specifies test methods for the determination of static, impact, and repetitive load strengths as well as disclosure requirements for postural support devices (PSD) with associated attachment hardware intended for use with an undefined wheelchair.

ISO 16840-4:2009 Wheelchair seating - Part 4: Seating systems for use in motor vehicles
ISO 16840-4:2009 specifies test methods and requirements for design and performance, for instructions and warnings and for product marking and labelling of seating systems intended to be used as a forward-facing seat in a motor vehicle when fitted to a manual or powered wheelchair. It evaluates the frontal crashworthiness performance of complete seating systems for occupancy by adults or children of mass equal to or greater than 22 kg.
ISO 16840-4:2009 only applies to complete wheelchair seating systems including attachment hardware, designed to be used with a wheelchair base tested as part of a wheelchair system that conforms to ISO 7176-19 performance requirements and that has securement points for use with four-point, strap-type tiedowns.
ISO 16840-4:2009 applies to seating systems designed to be used with occupant restraints that anchor either to the vehicle, the tiedown system, the seating system or the wheelchair base.

ISO 16840-6:2015 Wheelchair seating - Part 6: Simulated use and determination of the changes in properties of seat cushions
ISO 16840-9:2015 specifies apparatus, test methods, and disclosure requirements for generating aging effects in a seat cushion that reproduce those seen in use. It also provides methods of determining changes in the physical and mechanical properties of seat cushions based on their age and use. This part of ISO 16840 provides a set of tests that simulate wear and tear, which can be useful to validate warranty claims and to provide information about product, life, and performance limitations associated with product use.

ISO/TR 16840-9:2015 Wheelchair seating - Part 9: Clinical interface pressure mapping guidelines for seating

ISO 16840-10:2014 Wheelchairs - Resistance to ignition of non-integrated seat and back support cushions - Part 10: Requirements and test methods
ISO 16840-10:2014 specifies requirements and test methods to assess the resistance to ignition by smouldering cigarette equivalent of non-integrated components of a wheelchair intended to protect tissue integrity.
The test measures only the resistance to ignition by smouldering cigarette equivalent of the items tested and not the ignitability of the complete wheelchair. It gives an indication, but cannot guarantee, the ignition behaviour of the assembled non-integrated devices of a complete wheelchair.
This part of ISO 16840 does not apply to resistance to ignition of structural parts of a wheelchair, nor does it cover postural support devices. This part of ISO 16840 does not cover changes in resistance to ignition as a result of regular washing or use.
This part of ISO 16840 allows for the separate testing of removable non-integrated components of a wheelchair which are normally used in the horizontal plane (e.g. a seat cushion) from those normally used in the vertical plane (e.g. a back support).
This part of ISO 16840 describes testing an assembly of the composite of materials as used in the removable non-integrated component. The results of this part of ISO 16840 do not give any indication of the resistance to ignition of any of the separate individual materials of the test sample.
NOTE 1 The intent of this part of ISO 16840 is primarily to cover removable cushions whose described purpose is that of protecting skin tissue against pressure, shear, and maceration related damage.
NOTE 2 The requirements of this part of ISO 16840 have been set at a basic minimal level and are less severe than mandatory requirements in some countries.
Where practical, it is advisable that manufacturers use materials with superior resistance to ignition. The manufacturer is required to make the case as to why ISO 7176?16 could not be employed rather than this part of ISO 16840.
NOTE 3 Requirements for the control of risks from sources of fire created by electrical and electronic components are included in ISO 7176?14

ISO/TS 16840-11:2014 Wheelchair seating - Part 11: Determination of perspiration dissipation characteristics of seat cushions intended to manage tissue integrity
ISO/TS 16840-11:2014 specifies a method for determining the dissipation characteristics of simulated perspiration exposure on wheelchair seat cushions.
ISO/TS 16840-11:2014 is applicable to wheelchair seat cushions that include a cushion cover.

ISO/TS 16840-12:2015 Wheelchair seating - Part 12: Apparatus and method for cushion envelopment testing
ISO/TS 16840-12:2015 specifies apparatus, test methods, and disclosure requirements for characterization of wheelchair seat cushion immersion and envelopment properties using instrumented indenters to characterize the interface pressure of each indenter and the test cushion by measuring the cushioning effects of immersion and envelopment. This part of ISO 16840 can be considered to expand the characterization of products intended to manage tissue integrity (ISO 16840-2) and provide a standardized indenter for other wheelchair seating tests. It does not provide information specific to cushion performance for a particular individual user.
ISO/TS 16840-12:2015 includes a method that is specific to 220 mm and 255 mm indenters. Dimensions and loads are provided for the 380 mm indenter to allow for extension of the methods for bariatric applications.

ISO 10542-1:2012 Technical systems and aids for disabled or handicapped persons - Wheelchair tiedown and occupant-restraint systems - Part 1: Requirements and test methods for all systems

ISO 10542-1:2012/Cor1:2013 Corrigendum

ISO 23600:2007 Assistive products for persons with vision impairments and persons with vision and hearing impairments - Acoustic and tactile signals for pedestrian traffic lights
ISO 23600:2007 specifies requirements for acoustic and tactile signals for pedestrian traffic lights to assist in safe and independent mobility of persons with vision impairments and persons with vision and hearing impairments.
It is applicable to design, installation and operation of acoustic and tactile signals for pedestrian traffic lights.

Walking Aids and Assistive Products

Monday, November 16, 2015

Implementation of Electric Cars

The most popular method of powering automobiles is and has been with gasoline-powered combustion engines, despite the many other potential power sources that could be used. Cars are a necessity in many locations throughout the world where public transportation is not viable, especially in the majority of the United States. However, there has been a great deal of concern raised about the dependence on oil, a nonrenewable natural resource that emits significant amounts of carbon dioxide. Combustion engines can still be utilized sustainably for some time into the future, but finding a long-term, cleaner source of energy for cars is ideal. An incredibly likely option for this is the electric car, which, despite being around for some time, has yet to gain immense popularity.

The onset of the electric car was back in the early 1830s, when Scottish inventor Robert Anderson invented the first crude electric carriage, which was powered by primary cells. The first practical electric car was created by American Thomas Davenport just after this time in 1835. Throughout the rest of the Nineteenth Century, different inventors and companies improved upon this type of vehicle, making 90 percent of the taxicabs in New York City in the year 1899 electric. However, in 1908, Henry Ford popularized the combustion engine automobile through the release of the first Model T. With gasoline-powered cars being more affordable and giving consumers the opportunity to travel long distances, the electric car ceased to be a viable product in the 1920s. Despite the fact that it is long estranged from mainstream inclusion into society, interest in the electric car has still been prevalent since this time, especially in the Twenty-First Century.

In terms of mileage, the majority of electric cars are incomparable with the current gasoline powered cars that are on the market. Several different car manufacturers have been producing electric cars for some time now, very few of which can exceed 90 miles of travel on a single charge. This gives them potential for city use, but for long trips on highways or out in the country, they are certainly not ideal. To assist with extended travel, a car such as the Chevy Volt and the Ford Fusion Energi can be operated with only an electric engine until the majority of the charge is used up, after which a combustible engine switches on and the automobile begins to drive as a hybrid. This style of automobile is more efficient than traditional combustion engines, but it still requires the use of gasoline to function. The 100 percent electric car with the greatest driving range is the Tesla Model S, which travels over 200 miles on a single charge.

The cost of electric cars has also delayed their widespread implementation. Most electric automobiles are priced slightly higher than their conventional counterparts are, so it can be difficult for a consumer to justify purchasing an electric car for the financial reason of saving money on gas. The Tesla, despite being able to travel considerable distances on single charge, ranges in price from $70,000-$105,000, which is far out of reach for the common person. For electric cars to become more popular, one of the greatest changes needed would be to lower the price.

Another issue is the aesthetics, since people will always want their cars to look nice and appealing to justify the significant sums of money that they are required to spend on them. This quality has been lacking in some hybrids and electric cars in the past several decades. However, newer electric cars have been modeled more after conventional cars, which allows them to bear the same qualities as automobiles that are admired for their looks. A significant aspect of the design of Tesla automobiles was the inspiration from Lotus Cars. Elon Musk, the mind behind Tesla, is so obsessed with Lotus that he paid almost $1 million for the James Bond Lotus Espirit submarine car from the 1977 film The Spy Who Loved Me and modeled the Tesla after the cars that he admires. By using a style that has already been popular for its aesthetics, Musk ensured that his electric car has physical appeal to his consumers.

Standards for electric vehicles, addressing terminology and specifications for vehicle design, are available on the ANSI Webstore.