2983: Monocaster

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Monocaster
My competitors say the tiny single tiny caster is unsafe, unstable, and offers no advantages over traditional designs, to which I say: wow, why are you guys so mean? I thought we were friends!
Title text: My competitors say the tiny single tiny caster is unsafe, unstable, and offers no advantages over traditional designs, to which I say: wow, why are you guys so mean? I thought we were friends!

Explanation[edit]

A caster, also spelled castor, is a small unpowered wheel, usually attached to a swiveling base. They are typically found on carts and office chairs to make them easy to move, and may be placed on heavy appliances to facilitate movement.

Randall has proposed a variant of the skateboard with only one caster on the bottom, the titular "monocaster", and devoted most of the comic to a perceptual map showing the variety of wheeled vehicles. Market strategists and investors use such diagrams as a simple way of representing important differences between products or companies, but where a consumer might be more concerned with features like speed, cost, ease of use, or carrying capacity, this map focuses on the number of wheels (horizontal axis) and the diameter of those wheels (vertical axis).

Each axis uses a logarithmic scale, which is convenient for making the map look more evenly filled but also visually exaggerates the size of the "key gap" that the monocaster is filling, which can be described as "vehicle with a single wheel smaller than 25 cm". The nearest competitors appear to be a two-wheel skateboard sometimes called a caster board (wheel diameter under 8 cm) and a single-wheel self-balancing board resembling a Onewheel (diameter around 25 cm). The Onewheel is sometimes described as a monowheel (though these are traditionally larger like the "1920s monowheel" on the upper left). Randall appears to have combined these two names to create the monocaster. This gives up several of the competitors' features - the caster board's two wheels provide enough stability to propel the vehicle manually, while the Onewheel's single wheel is wide (assisting with sideways balance) and powered by a self-balancing mechanism.

The result resembles a "Sphere-and-ring" balance board, or other types, though these provide limited locomotion potential. The joke depends on the caster's obvious impracticality in this role: the hole in the market was open for a reason. The obvious drawback to any single-wheeled vehicle is that it's difficult to balance: the rider has to avoid falling forward or backward, as well as to either side. This is a major reason why one-wheeled vehicles are uncommon to begin with, but those vehicles which do exist compensate by using relatively large wheels, driven either by human power or a motor, which creates rotational inertia and allows the rider to balance simply by leaning forward.

A single, small, undriven wheel eliminates these balancing forces, meaning that the user would essentially need to balance on a single point. Also, most casters swivel, meaning that the balance point would move around under the rider's feet and make it even more difficult to balance. In addition, there's no apparent means of propulsion, which means the only way to move forward would be to either roll exclusively downhill, or use one foot to push off the ground. Either strategy would make retaining balance almost impossible.

Multiple-wheeled vehicles greatly reduce the issue of balance simply by having multiple points of contact with the ground. The size of the wheels varies greatly; small, rigid wheels are generally suitable only for flat, smooth, rigid surfaces at relatively slow speeds, while vehicles expected to handle high speeds and varying road (and off-road) conditions will necessarily have larger wheels.

The "monocaster" design offers no advantages and would be nearly unrideable, making it obvious why such a vehicle has never been seriously proposed.

The title text extends the joke by listing the disadvantages mentioned above, but not providing a rebuttal. Instead it only attempts an emotional appeal by saying that the competitors are being mean and by commenting that Randall believed they were friends.


Vehicle Number of wheels Wheel Diameter Explanation
1920s Monowheel 1 3 meters A monowheel is a vehicle in which the rider sits inside a single, large, hollow wheel. Versions have existed which were hand- or pedal-cranked, but the "1920s" version portrayed here is apparently motor-driven. These vehicles have generally been seen as novelties, as their stability and practicality issues limit their usefulness for actual transport.
Unicycle 1 45 centimeters Probably the best known single-wheeled form of transport, a unicycle consists of a single wheel, usually driven directly by pedals, with a seat mounted on top. Due to their difficulty, they are most commonly used as novelties and for comic performances, more than as practical transport.
OneWheel 1 20 centimeters A one-wheeled electric skateboard in which the user stands on both sides of a large, central wheel. The design self-balances by increasing the velocity as the user leans forward. This allows balancing and speed control to operate in a single motion.
Bicycle 2 45 centimeters A two-wheeled, pedal-driven vehicle. The relatively simple, inexpensive and efficient design of these vehicles makes them practical for transport in a variety of situations. As a result, they've long been among the most popular and widely-produced vehicles in the world.
Scooter 2 8 centimeters (*) A two-wheeled vehicle driven either by pushing with a foot or by an electric motor or fuel-powered engine. Scooters are ridden both for recreation and as a form of transportation in cities.
Roller shoe 2 1 centimeter (*) Shoes with small wheels built into the back end of the soles, putting them underneath the wearer's heels (which is what the brand-name "Heelys" is derived from). They allow the user access to wheeled movement by pushing off the ground and balancing on the slightly protuding wheels. They are not as fast or comfortable as a dedicated wheeled vehicle, their rolling action is limited to sufficiently flat surfaces and they are not as easy as regular shoes to simply walk in. However, such shoes allow for some degree of both walking and rolling without having to carry a separate wheeled vehicle, or necessarily having the baseline difficulty of other 'fuller' versions of wearable skates.
Tricycle 3 20 centimeters Appears to be a "Big Wheel" type child's toy, which actually have smaller 'trailing wheels', rather than either upright or recumbent style cycles for adults which usually match the wheel-sizes of their bicycle equivalents.
Scooter (three-wheeled) 3 3 centimeters (*)
Monster Truck 4 2.5 meters Monster trucks are vehicles equipped with (usually four, but sometimes more) outsize wheels. They are almost always driven as part of events where specifically trained drivers use them to perform dangerous stunts and crush smaller vehicles. Because of their size, the danger to other vehicles, often very poor mileage, and design choices that can be in violation of local laws and regulations regarding motorized vehicles, monster trucks are not driven on public roads and have to be transported in dedicated trailers, making them poor choices for transport where one has to leave private property.
Car 4 50 centimeters Cars are motorized vehicles designed to move one or more people and an amount of goods around fast. While almost all cars have four wheels (discounting reserve wheels), there are a few that have more than four (certain limousines) or fewer (the Reliant Robin only has one wheel in the front). Cars are more expensive than most options on the chart due to their higher cost, the use of fuel and maintenance requiring specialized knowledge (and sometimes replacement parts), they make up for this with their speed, access to (at least in most of the world) an extensive system of roads and refueling stations, the ability to move a number of people and goods (how much depends on the exact type of car and how much of either the car is already carrying), and the comfort of being in what is almost always an enclosed and air conditioned compartment. Because of the potential danger of an object of a car's size and speed, drivers are required to perform a test of their ability to both control the vehicle and be aware of other traffic to obtain a license to drive one. Cars are a common source of leisure, with interests ranging from driving them normally, driving them as part of a race, maintaining them or enjoying luxury cars.
ATV 4 20 centimeters (*) ATVs or "all-terrain vehicles" are unenclosed, handlebar-steered vehicles designed for off-road riding. They have four, large, low-pressure tires and a robust suspension system to accommodate rough terrain. They generally aren't designed to carry passengers, and have limited cargo capacity, which limits their usefulness for regular transport. They're generally used either for recreation or for transport in areas without well-maintained roads.
Skateboard 4 2 centimeters (*)
Three-Wheel Skates 6 4 centimeters (*) Three-wheeled skates are a type of inline skate (shoes with a line of wheels affixed underneath the shoe) that differ from the more commonly used four wheeled inline skates by having three larger wheels. They are inexpensive and easy to maintain, but they require significant skill to use effectively and the user is reliant on smooth surfaces to skate around on. Another downside is that the wheels cannot be removed from the shoes, requiring the user to either carry an extra pair or have an extra pair at their destination.
Roller Skates 8 2 centimeters (*) Roller skates are shoes with small wheels underneath them in a rectangular pattern. This makes roller skates much more stable than inline skates, allowing users to stand on them with more ease. Like inline skates they are cheap and low maintenance, but in order to move any significant distance without support they require a skilled user, smooth surfaces and the user needs backup shoes when taking them off (though there exist strap-on roller skates).
Semi-Trailer Truck (Articulated Lorry) 10-18 1 meter A semi-trailer truck is a motorized vehicle designed to pull trailers that can be easily decoupled from the truck itself. This allows the truck to switch trailers and move a different cargo without having to unload the trailer. The name in brackets that was used here (articulated lorry) is a name most commonly used in British English (or "artic", for short), with articulation meaning that the truck can swivel at the point where the truck connects to the trailer. This allows for the truck to make much tighter turns than if it were one long vehicle, which is another advantage of this configuration, with typically more stability than with a drawbar attachment. Trucks are designed to haul cargo for long distances, with the cargo in question being either too heavy or too large to carry with a smaller hopper, tanker, hard-/soft-sided container or flatbed placed entirely upon a single truck chassis. They are driven either by drivers employed by a transport company, or by self-employed individuals who haul cargo for a living. A specialized license is required to drive one, and because of their size (even without a trailer), trucks have more limitations on where they can drive and park than normal cars. Like cars, trucks are a source of leisure, but because of the higher cost to purchase, maintain and drive them, they are more often enjoyed for their aesthetics rather than actually driving them for leisure. There are events like races for trucks, and trucks can be given elaborate paint jobs to have them stand out.

The number of wheels is for both the truck and a trailer, which can each differ vastly between vehicle configurations. The truck in the comic has five obvious axle-sets (thus at least ten actual wheels): a single pair of front wheels, two pairs of trailer-bearing rear wheels and two pairs of wheels on the trailer itself. The drawing of the truck actually spans the axis range of three wheels (unlikely to be true, and the minimum for a tractor-trailer would normally be six) all the way up to 16, so it's not entirely clear which number (≥10) Randall intends this one to portray. Most of the other illustrations are roughly centered over the relevant number of wheels, but applying this to the truck implies six wheels, which is clearly wrong as illustrated.


(*) It seems that Randall has made some mistakes in regards to the wheel sizes, especially in the centimeter range of the diagram. Most of the vehicles have bigger wheels and the number would suggest hat he meant inches instead of centimeters. Alternatively, he may have mistakenly recorded the wheels' radius instead of its diameter, as intended.

Transcript[edit]

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[A chart picturing many wheeled vehicles with a caption below the chart window. The vertical axis is labeled "Wheel Diameter", logarithmic from 1cm to 5m. The horizontal axis is labeled "Number of wheels", logarithmic from 1 to 16. From top left to bottom right, there is a person with a cap, seated in a circle, labeled "1920s monowheel", a monster truck with a skull and a lightning bolt on the side, a lorry (truck), a Cueball on a unicycle moving back and forth, a Cueball on a bicycle, a car, a Cueball using a Onewheel, a Cueball on a child's "Big Wheel" tricycle, a Cueball on a quad, a Cueball standing on a scooter, a Cueball standing on a board with one small wheel bellow, circled and labeled with two question marks, a three-wheel scooter, a skater, a Cueball using three-wheel skates, labeled "three-wheel skates", a Cueball crouching and using skates, and a small Cueball using shoes with wheels (Heelys) moving forward.]
Caption: My new monocaster board fills a key gap in the wheeled vehicle market.


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Discussion

Unicycles aren't (or at least aren't usually) chain-driven. I might try to fix that if my phone stops being so slow that it feels like I'm using a 90s PC to do this. Maybe a restart will help. Rebooting in 10, 9, 8... 172.70.91.76 07:46, 10 September 2024 (UTC)

I just went in and Actual Citation Needed it (seeing lower comment, when editor reloaded this page for me, forcing me to rewrite, that may have changed now).
  • It doesn't look like a chain-drive. Could be hub-geared, but not the same thing.
  • Chain-drive to raise the rider (most of the mass) up higher will raise the CoG.
  • 'Underslung' chain-drive (see 1880s example, here?) has problems. Pedals hitting the ground would be one of them, unless your wheel was indeed significantly larger...
  • ...and if it is (perhaps for better off-roading?), this intrinsically pushes up the CoG. Perhaps you are trying to lower it slightly, again, then. But you can't bring the saddle (and crotch!) lower than the now higher top of the wheel. ("Timeline of Bicycles" version excepted, assumed assymetric? In some manner?)
Add to that a few niggles about the bicycle. Not sure if intended to be a Moulton-style one (wheels maybe the classic 17", frame totally wrong) or a roadbike-style-ish one (frame relatively Ok, as drawn by someone not fully adhering to the design, maybe confused by some MTB variations, but clearly not in the ~27" wheel range, give or take). Of course, wheels are neither concentric nor circular, so depends a bit on which bits of the 'circles' are right for the intended arc and which bits ended up more casually doodled. 172.70.91.99 08:51, 10 September 2024 (UTC)
There also don't appear to be any pedals on the bicycle, with the rider instead resting their feet on the bottom bracket. Which is... unorthodox.141.101.99.135 11:16, 16 September 2024 (UTC)
Charitably, the nearside foot (and leg) is positioned at the top-going crank position, with the farside one stretched down to the down-angled crank/pedal, but the chainring is a solid disc (and a radius to match the crank-lengths), rather than the usual "with many cutout bits" and a few inches smaller in radius than the pedal-extents.
Though the fact you can see the frame (the downtube, seat-tube and at least one of the chainstays) where they meet at the bottom-bracket means that the disc-chainring is mounted with the left pedal+crank (the lowered one), rather than on the side of the RHS pedal+crank (the one raised), as per usual. But that's hardly the weirdest bit about the depiction. ;) 141.101.99.88 14:59, 16 September 2024 (UTC)
AFAIK, unicycles aren't GENERALLY chain-driven, but tall ones are (to put the peddles where the rider can reach them, but raise the rider up, often to a second story of a building). That said, I don't see a chain here, but I also don't see one in the description, so obviously sorted out by now. NiceGuy1 (talk) 06:13, 15 September 2024 (UTC)

Hmm, Randall missed an opportunity to put a Penny-Farthing in there... though I'm not sure how that would have categorised given that it has two wheels of different sizes. --172.68.205.178 08:19, 10 September 2024 (UTC)

He has a "Big Wheel Trike" (child's low-rider style thing) in there. On the logarithmic scale, and imprecise reference point (bottom/middle(/CoG,where different)/top of wheel/vehicle/rider/whole?), both the big front wheel and the small trailing wheels colpd be in the right place-ish, although having it slightly inclined could put them in the (place Tandall considers to be) exactly right place. ((Note also where the 10(?)-wheeler truck-and-trailer is placed horizontally vs the possibly relevent "number of wheels".))
You could do something similar with the Old Ordinary (i.e. "Penny-Farthing"), either make it roughly right or depict going up a marginally steeper hill. 172.69.194.142 09:04, 10 September 2024 (UTC)
I'd say ignore the small wheel (would crowd with similar-sized wheels) and place according to the front wheel, might be easier to find room there. :) Agreed, missed opportunity, that front wheel is particularly large. Also, when talking about number of wheels and large wheels, how could he miss the BelAZ_75710? A lot of people have been introduced to the concept, 2 wheels per corner I think and I think the wheels are like 8 feet tall in diameter! (I guess like 2.5 meters or so, I'm just pretty sure it's well over my own height of 6'2", which I know is around 190cm or nearly 2m). NiceGuy1 (talk) 06:42, 15 September 2024 (UTC)


Re: unicycles, the COG thing doesn't look right either, but I was distracted by a (thankfully) now-deleted troll comment before and actually fixing the description is beyond my skills, especially on so little sleep.172.69.43.184 08:35, 10 September 2024 (UTC)

i had good intentions, we need to call randall out --172.69.194.122 09:44, 10 September 2024 (UTC)
If you mean your calling out the other point, that has been deleted anyway: Randall doesn't read this site (that we know; and, if I had a site such as this made for my works, I'd think it wisest to stay clear), so he probably won't get your 'message'. This particular comic doesn't even have the slightest connection to that subject, so not even the page to say anything about it. And the point made (even if it was a valid one... it presupposes that there are no nuances and compromises, that one cannot have a complex set of opinions that neither wholly match nor wholly mismatch your opinions) was also absurd, when you consider how the other party involved has proven to be even more so. I won't dignify this issue further by putting names and places here, it really isn't the forum for it. But please realise (if you don't already) that your irrelevent point is out of place here. And most places on this site that you/others like you may have tried such messaging on before. Go to /pol/, or your favourite forum's dedicated boards/threads. Ok? 172.70.85.19 12:26, 10 September 2024 (UTC)
Call him out for *what* exactly? 172.68.70.135 12:05, 10 September 2024 (UTC)
As I dare to hint, just above, someone thinks Randall has a wrong personal opinion on some current issue. Which has nothing to do with this comic. 172.70.85.19 12:26, 10 September 2024 (UTC)
You can check the history of this Talk section like I just did, some weirdo wrote a wild rant about Randall's politics (seems out of left field and based on nothing) which had nothing to do with the comic beyond ranting about Randall and Randall being the author. It was the original first comment. Most proper deletion, I say. NiceGuy1 (talk) 06:31, 15 September 2024 (UTC)
Actually, I think the rant came more out of right field, but I agree with the rest of that assessment... ;) 172.71.26.23 13:54, 15 September 2024 (UTC)
actually i support the green party :) 172.69.79.138 07:18, 17 September 2024 (UTC)

As a unicyclist myself, I don't think the unicycle is easier to balance because of a lower center of mass and a chain drive. As a few others have mentioned, they don't normally have a chain drive, although there are a few specialist ones that do. Normally, the cranks are just attached to the hub so you can directly control the speed of the wheel at a 1 to 1 ratio, which makes it easier to balance on. The other thing that would make the unicycle easier than the monocaster is that you can control what direction the wheel is pointing by turning the seat with your thighs. 172.68.186.128 09:22, 10 September 2024 (UTC)

Love the log-log scale. Now let's see the zoomed-out version, with orders of magnitude more wheels and orders of magnitude larger diameters. 172.71.166.230 13:59, 10 September 2024 (UTC)

The scale if off either way. Or Randall wrote centimeters while he meant inches... At least for some cases. Examples: he placed the skatebord at 2cm while skateboord wheels are at ca 5cm - which are approx. 2 inches. Scooter wheels are approx 8.5 inches, not 8.5 cm... The car is mostly fine, albeit it would be a rather small car at ~50cm (a 19 inch (50cm) wheel designates the size of the rims, not the wheel) Elektrizikekswerk (talk) 15:18, 10 September 2024 (UTC)
out of all people i would think Randall would be the last one to use a non-SI unit to measure distance. --Markifi (talk) 17:45, 10 September 2024 (UTC)
He usually prefers SI units, yes. Elektrizikekswerk (talk) 10:03, 11 September 2024 (UTC)

I have NEVER heard anyone call inline skates "three wheel skates". 141.101.109.193 19:04, 10 September 2024 (UTC)

As a quad skater through most of my youth, the depicted "three-wheel skate" was only called "inline" skates. Not sure where this 3-wheel designation came from! RandalSchwartz (talk) 21:59, 10 September 2024 (UTC)
I too thought the term “three-wheel skate” seemed odd, and thought “inline skates” might be more appropriate. Then I remembered that in fact, most inline skates have four wheels… a memory that a quick Google image search seemed to support. So I guess a three-wheel skate is a special case of inline skate, rather than the default implementation. 172.70.160.137 06:56, 11 September 2024 (UTC)
Both variants exist and the three-wheeled version has generally bigger wheels - so the relative depiction of both variants in the diagram is correct. But their position regarding to wheel size is not. See my comment above Elektrizikekswerk (talk) 10:03, 11 September 2024 (UTC)

title text sounds like beret guy ngl--1234231587678 (talk) 23:38, 10 September 2024 (UTC)

Not a single mention of Pollux? Wikipedia 172.68.70.122 11:53, 11 September 2024 (UTC)

Disconcerting that this explanation does not describe any of the vehicles, instead entirely making one-sided arguments regarding the title text. 172.71.175.16 15:53, 11 September 2024 (UTC)

I was considering a tabular list of all subjects, when I had time, at least to the Preview stage. Very brief: 'Vehicle' (wikilinked, as appropriate)/№ of wheels/typical size of wheel(s)/Typical use. No long paragraphs intended. Might need a range in the size column (possibly some in the # of wheels column). If someone gets there before me, though, I wouldn't mind. :p
...and I just discovered that the # 'key', in the numbers 'screen' of this touchscreen keyboard has ”№” as a long-press alternative! How long have I been using this and hadn't realised? (Four years. That's how long.) 172.70.90.137 16:43, 11 September 2024 (UTC)


DougM (talk) 16:35, 11 September 2024 (UTC)Missed opportunity to bring in the Letourneau l2350 loader, which I think has the largest production tires in the world at 4m, outshining those monster trucks (Bigfoot I think never had tires bigger than 3m).

I notice also a hole regarding ~30cm, multi-wheel. I say that space is filled by those amusement-park little trains. Yesss, they're "separate wagons," however, as it's several attached wagons operating together as a unit, for practical purposes, I say those trains constitute "one single" vehicle. Some have a very ingenious directional drive system, so wagons follow each other in the same path instead of a cathenary, for example in Disney; I was fascinated.Yamaplos (talk) 17:15, 11 September 2024 (UTC)

No mention either of the Rip Stick, which successfully employs only two castored wheels for locomotion. 172.68.23.189 18:11, 11 September 2024 (UTC)

Is there any reason the title text uses "tiny" twice? 172.71.150.3 22:38, 11 September 2024 (UTC)

I'm guessing it's meant to be interpreted as the tiny "single-tiny-caster" 172.71.150.2 22:50, 11 September 2024 (UTC)

(Inception Sound Effect)[edit]

Somewhere in the far corner of the chart:

Bagger 288

Fephisto (talk) 20:26, 11 September 2024 (UTC)

Somewhere in the upper right (but closer than that), the BelAZ_75710, what a missed opportunity! I think it has 8 wheels, 2 at each point a car has 1... I think each wheel is like 8 feet in diameter! NiceGuy1 (talk) 06:13, 15 September 2024 (UTC)

What a missed opportunity to include the 14 wheeled flowboard Scab (talk) 10:17, 13 September 2024 (UTC)

Since regular roller skates are pretty much gone now, seems wrong to miss standard rollerblades (4 wheels per skate, not the 3 Randall specified). Except it would go very close to the skates - I think the wheels aren't quite the same size - I guess that's why, but seems strange to choose the classic 2-by-2 skates over currently common rollerblades... NiceGuy1 (talk) 06:13, 15 September 2024 (UTC)