Bikes on Mars? - Don't laugh!

Rxke · 2004-01-31 13:53:49

Didn't see it here, nor on any other site (didn't look too hard, though)

Considering bikes are *the* single most effective non-motorised way of getting somewhere, wouldn't it be worthwhile to think about them?

Ok, it's a funny idea, guys 'n gals in suits on a bike, but those things are fairly cheap, simple to repair etc...

you could make three-wheelers with an extra cart, if you wish, and they'd double as exercise equipment, too.

imagine a base with semi-well cleaned 'roads', wouldn't it be simpler to take a quick jump on a bike to the nearest reactor, powerplant, whatever, it being half a mile away...if you take a buggy, you have to check the engine and stuff, plus they weigh a *lot* (transport to Mars) compared to a sturdy bike.
you could ship dozens, insttead of one, two personal mini-rovers...
has there been experiments, and if not, why not? People afraid of being laughed at? The current suits much too stiff to do that?

Last edited by Rxke (2015-10-12 07:51:10)

Byron · 2004-01-31 17:43:56

Why not use Segway people movers? Those would work even better in Martian gee than here, I would imagine, and they don't take up room at all. They'd have to be used on paved ground, I suppose but that would be true for bikes as well, and using a Segway would be easier while wearing a suit, etc.

B

Rxke · 2004-01-31 18:04:03

But that's again complicated machinery, that would be hard to repair... and if you made an 'off-road' bike, you could traverse semi rigid terrain, like gusev, i can's see a Segway doing that...

A Seg would need a lot more maintenance, too, batteries etc, keep its electronics shielded and in working temperature range... It would quickly become a very expensive toy, better to use a 'decent' 4 wheel vehicle (electric) then...

i'm thinking about 'early' phase here, when roads are just rougly leveled, a seg would require massive man or robot hours to build roads that it can negociate, a bike is just a bit more flexble in that perspective (and cheap)

Adrian · 2004-01-31 19:24:04

One problem is fines and dust gumming up the workings of the bike. You could always have an internal chain system but if it breaks it's much more work to fix.

Rxke · 2004-02-01 02:49:17

Yes, that was my first thought, too... those fines will, however, be a *mayor* tech horror for virtually everything we use on Mars... And i think it'll be much easier to clean a chain (compressed gas etc) than a electric motor.
I'm more concerned abot the other moving parts, like steering wheel, and wheels, but that's a problem *all* moving vehicules will have...

Adrian · 2004-02-01 06:10:44

I wonder, is there any information on the web from NASA or whoever about how they've engineered rovers and landers to cope with fines? Are there any special sealants or joints that they use?

Shaun Barrett · 2004-02-01 06:14:49

When I was a kid, we would ride bikes on roads and paved paths and we'd even ride on grass if need be. But we'd never ride on sand because the wheels would sink in and the effort of pedalling would become too great.
I'm trying to imagine cycling on Mars but all I can see is dust and sand and bicycle wheels bogged down to the spokes.

We may need to characterise the nature of the martian surface a little better before sending bikes and, even then, I think we'd need to consider things like much wider tyres to decrease the force per unit area and prevent bogging.
But I'm not saying it won't work.

Palomar · 2004-02-01 16:02:13

I'm trying to imagine cycling on Mars but all I can see is dust and sand and bicycle wheels bogged down to the spokes.
We may need to characterise the nature of the martian surface a little better before sending bikes and, even then, I think we'd need to consider things like much wider tyres to decrease the force per unit area and prevent bogging.
But I'm not saying it won't work.

*Could we put something like hubcaps over the spokes? I suppose dust particles would still seep in, but covered spokes would keep a lot of dust and sand out...if hubcaps or something similar are even feasible.

I don't know much about even simple mechanics, I admit.

[http://www.fastgt.com/forsale/hubcaps.jpg]Hubcaps (yeah, you probably know what I mean, but they might be called by different names even in Australia and elsewhere...I don't know)

--Cindy

Shaun Barrett · 2004-02-02 01:37:59

It wasn't actually the sand in the spokes per se that worried me. It was the thought of the wheel rims and tyres sinking into the regolith and making pedalling so hard.
Maybe we could make the tyres fatter to decrease the force per unit area(?). Perhaps, together with the lower martian gravity, that would be sufficient to solve the problem(?).

This whole question of mobility on Mars is certainly an interesting one. Experiments have shown that while the human form under terrestrial gravity of 1g is most efficient in a walking mode (i.e. more kilometres per gram of sweat ... miles per ounce for our American cousins! ), in 0.38g on Mars a loping run is easiest.
A bicycle ride on Earth certainly beats trying to run at a similar pace, assuming the ground is smooth enough, but is that necessarily the case on Mars? Might the lesser difference in energy expenditure there between loping and pedalling make the bicycle redundant?
???

Rxke · 2004-02-02 01:53:20

*good question* !

Read that article, too, somewhere, sometime...
totally forgot about it, though...

Michael Bloxham · 2004-02-02 03:31:25

Well... I beleive there are beach bikes, or trikes, with large plastic (inflatable?) balloon tires. And you can rent them at popular beaches somewhere... But beach trikes on mars? I dunno... ???

Rxke · 2004-02-02 12:40:12

Hee hee, dont' know those things, but i'm imagining *very* big balloon tyres, able to do very rough terrain...They could be interesting in an emergency, imagine your rover breaking down, no way to get back to base on foot before your life supply runs out, but you happen to have a lightweight frame and inflatable balloon tyres on the roof of your rover...

Too far out and it wouldn't do you any good, granted, but it could help you to the nearest emergency cache...

Mad Grad Student · 2004-02-04 22:01:45

I like this idea, good job, rik! Bikes are simple, efficient, lightweight, and would probably work on Mars, perfect for short-range exploration. I imagine that the best way to use bicycle technology would be in the form of trishaws, effectively big, huge tricycles. The astronaut's life-support system would clip on to the seat-back, and the only the legs and arms would need to be moved to pedal and steer.

I don't think that sinking into the regolith would be a very big problem, but if it was it could be solved simply by getting thicker tires to spread the weight out more evenly. The two MERs are both over 400 pounds and supported by only those six skimpy lego technic wheels. One of these trishaws would have probably about the same weight distribution per wheel, so they really wouldn't run into too much trouble. If only someone could get NASA to ditch their expensive and complex motors.

Rxke · 2004-02-04 23:35:43

*smiles*

if the Mad Grad Student likes it, I'm happy!

Personally, I think it won't be too comfortable to drive a bike or rickshaw on Mars, but it would be some kind of workout (in a suit? hope cooling works right)
And it's KISS, if everything else break down, you'd still have a chance to move (hmmm... would it be possible to transport wounded people that way? Otherwise you'd need 2 people, no way to carry a backpacked person, as they tried in simulations...)

And, yes, i got the idea partially by looking to the Rover imprints on Mars, 'hey, the soil looks rather compact...'

Brian Hanley · 2004-02-18 14:39:14

Let's see. At 38% of earth weight, with additional gear on board for suit, and miscellaneous carrying minus a few pounds because the bike would come from earth, let's compare weight.

On earth, a bike and rider is about 180 pounds. 150 for rider, and 30 for bike and stuff carried. (We are talking utility bike here. With standard Mt. bike tires, the contact patch is about 5 square inches per wheel, with about 70% of weight on rear. So, you have about 126/5 = 25 PSI on the rear, and about 54/5 = 11 PSI on the front on earth.

On earth, by creating dual front and rear wheels, riders in th Iditabike can ride through snow, which presents similar problems to sand. That would tend to indicate that the compression strength of snow/sand is on the order of 12 PSI. That correlates reasonably well with figures for ultra low pressure farm tractors which use special radial tires inflated to 6-8 PSI. That enables the tractor to be used on wet, soft, muddy ground without damaging the soil from compression or creating ruts.

So, multiplying those mountain bike figures by 0.38, one can establish a pretty reasonable guesstimate of whether a bike could be ridden on Mars over the surface.

Bike and rider + stuff total weight = 180 * 0.38 = ~70 pounds
Rear wheel PSI of ground contact = ~48 lb / 5 square inches = ~ 10 PSI
Front wheel PSI of ground contact = ~21 lb / 5 square inches = ~ 4-5 PSI

So I think the answer is yes - a bike would work very well on Mars for transportation with little or no modification.

Brian Hanley · 2004-02-18 14:42:57

Relative to the fines, based on my experience with desert grit, modern sealed hubs wouldn't be a problem. Chains might need a little work, perhaps changing now and then, but people ride bikes for as long as a decade without changing chains sometimes.

Wouldn't have a corrosion problem I don't think.

Not sure how tires would perform in Mars temperatures. I suspect they would do just fine though.

quasar777 · 2004-03-09 13:47:17

there`s an excellent article on just this subect on the artemis project site. yeh i know don`t mention the moon around here. the place ya wanna check out for all ya wanna know about bikes is: [http://www.ihpva.org][http://www.ihpva.org]www.ihpva.org . there are many humanpowered vehicles which would work in this situation. the 3 wheel vehicle mentioned is called btw; Aquabike. & it`s belt-driven rather than chain. mention in the artemis is treadle drives or linear, rather than cyclic which is commonly used. i`ll see if can digup the url for it. btw spacecamp in huntsville ala has a "moonbuggy" race every year. i`d imagine as in scubadiving, marscrew would be on a "buddy" system constantly. so 3 wheel bikes would probably be 2 or more seats which makes an Aquabike even more appealing. btw i do seem 2 recall a wheelchair design which had "mushy" wheels.

quasar777 · 2004-03-15 15:06:40

[=http://www.aquacycle.com]www.aquacycle.com

quasar777 · 2004-03-27 16:50:49

there are many bikes w/ sealed components available. there should be a material marsbikes could use which would magnetically or something repel dust on exposed components.

Rxke · 2004-03-27 17:36:10

quasar.... I have the impression you like the idea...

They should be easily maintainable, otherwise there'd be no advantage towards a motor-driven equivalent...

As it is, we simply don't know enough about the effects on hardware by the dust to come up with a simple device, so i guess we'd come up with a much too complicated bike...
Maybe someday in an outpost, a bored engineer will build one for himself; let's hope his name is Wright, and he has his brother working next to him :;):

~Eternal~ · 2004-03-29 13:37:11

Not everyone knows how to ride a bike

SBird · 2004-03-29 13:44:25

Compared to learning to fly a jet - a requirement for any spacecraft pilot, a bike should be trivial. Plus, you never forget how. I went for about 15 years without touching a bike when I was a teenager, sat on a bike a few years ago and just rode off like nothing. I'm pretty srue that you retain muscle memory for a bike longer than, say walking.

As for fines, I really can't see that as being a problem. Modern mountain bikes used sealed hubs that have a pretty high tolerance for particulate matter. The only spare parts you'd have to take would be things like chain links and wheel hubs. That would be a trivial amount of weight for numerous spare parts.

Incidentally, the Army has been investing in bikes heavily and a number of commando units are now bike equipped. In field tests, bike equipped soliders were able to go cross country to an objective, rescue 'hostages' and get them back to base before the foot-mounted team even got to the objective.

Rxke · 2004-03-29 22:34:02

Not everyone knows how to ride a bike

Now that is something i was taking for granted.. That everyone *does* know to ride a bike... That is, talking as an European, where generally, kids can't wait to get their first bike... It's almost some kind of initiation rite around here...

SBird · 2004-03-30 14:50:36

As an America, at least as a West Coast American, pretty much everyone here has tooled around on a bike to some extent. Lots of people haven't ridden a bike in years but most kids learn at some point.

quasar777 · 2004-03-30 17:30:23

http://www.asi.org/adb/06/09/03/02/091/moon-rover.html or google human powered lunar rover. yeah yeah i know we don`t like the moon here.

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#1 2004-01-31 13:53:49

Re: Bikes on Mars? - Don't laugh!

#2 2004-01-31 17:43:56

Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

#4 2004-01-31 19:24:04

Re: Bikes on Mars? - Don't laugh!

#5 2004-02-01 02:49:17

Re: Bikes on Mars? - Don't laugh!

#6 2004-02-01 06:10:44

Re: Bikes on Mars? - Don't laugh!

#7 2004-02-01 06:14:49

Re: Bikes on Mars? - Don't laugh!

#8 2004-02-01 16:02:13

Re: Bikes on Mars? - Don't laugh!

#9 2004-02-02 01:37:59

Re: Bikes on Mars? - Don't laugh!

#10 2004-02-02 01:53:20

Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

#17 2004-03-09 13:47:17

Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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Re: Bikes on Mars? - Don't laugh!

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