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#76 2018-03-03 16:31:04

Void
Member
Registered: 2011-12-29
Posts: 2,108

Re: Mars Cart

I like that, and I am not trying to do a topper here. 

3D printed motor: (So, two ways)
http://www.instructables.com/id/3D-Printed-DC-Motor/

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#77 2018-03-03 17:13:52

louis
Member
From: UK
Registered: 2008-03-24
Posts: 3,058

Re: Mars Cart

Great video.  I've noted before that electric motors are relatively simple and could be produced by an early colony largely from ISRU materials.  45 Kws is pretty powerful - enough to run a car I think!

SpaceNut wrote:

This is how one might make a motor or generator from insitu materials 45Kw DC Brushless motor construction


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#78 2018-03-03 17:18:15

Antius
Member
From: Cumbria, UK
Registered: 2007-05-22
Posts: 1,003

Re: Mars Cart

Some interesting concepts here.  Tracked vehicles are less likely to get stuck in soft terrain than wheeled vehicles.  But they are heavier and less energy efficient.

I wonder if a hybrid electric vehicle could be a good option for Mars.  A short range 40km battery, which can be charged with roll-out solar panels.  An IC engine mounted to a generator for when greater speed and power are needed or when traveling close to the poles.  Wheels could be some kind of fibre reinforced polymer.

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#79 2018-03-04 04:34:01

elderflower
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Registered: 2016-06-19
Posts: 743

Re: Mars Cart

For Mars service an IC engine isn't likely to work. You have to carry oxidant as well as fuel. Atmospheric CO2 could be used but you need a fuel that won't coke your engine up. Better to use a Sterling or Brayton engine (external combustion) if you want to use the CO2 as an oxidiser, as a coked up heat exchanger is relatively easily switched and/or cleaned.
I posted elsewhere about self heated tires by filling them or compounding them with radioactive elements. I prefer the filling option because it is renewable and can be adjusted for different missions. An alpha or beta emitter might be best to restrict penetration of the particles, and it would need to be a volatile compound so that a puncture or leak would dissipate rather than create a concentration of your radioisotope. I still prefer tracks if they can be done, though.

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#80 2018-03-27 20:21:28

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

http://www.ecmweb.com/content/selecting … efficiency

Motor ratings and nameplates are standardized in terms of horsepower and speed, with no mention of torque. However, you can relate horsepower and torque with the following equation: Horsepower = Torque (lb-ft) x rpm/5250

http://www.kylesconverter.com/power/foo … horsepower

calculate the peak power and torque produced by an electric motor

https://wikivisually.com/wiki/Electric-vehicle_battery

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#83 2018-03-30 20:34:41

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

The simularities of a pancake permanent magnet generator and of a motor aka axial flux are something that will be a somewhat simple construction for the early conlony on mars. Not to meantion something that we may need to learn how to fix.
Project home page with links on the left side for building the other parts.

How to make the Stator while this is for a windmill its the same generator that is designed for low RPM rotation to achieve power. Since we are coverting the AC to dc the rotation speed the frequency will not be an issue as we are not looking to sync it up for regular power appliances. The DC would be then fed into a charger circuit that would charge batteries.

The magnet rotor plate construction will allow for multiple stators and plates to be used to build up higher levels of wattage as needed. The axial flux design uses 2 of these plates to create the feild path north to south for each coil and then swaps south to north on the other plate.

The generators output is about 48 Volts with a max 30 amps for the approximate output of around 1200 watts at around 140 RPM with the output wattage going up with the increase of RPM.

https://ashwoodselectricmotors.com/perm … ux-motors/

Building a triple stator axial flux motor has lots of the actual construction

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#84 2018-03-30 21:30:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

Permanent Magnet Spiral Motor for Magnetic Gradient Energy Utilization: Axial Magnetic Field in a Wankel design...

Experiments with Spiral Magnetic Motors

https://www.freeenergyplanet.biz/energy … ngine.html

http://www.cheniere.org/misc/wankel.htm

Simular as the other motor design in that a stackup of platters offset by the phase count relative to the platter count or 360' / 3 for 3 platters or 120' seperation of energy to make the rotation happen.

https://evmc2.wordpress.com/2011/12/29/ … gy-motors/ links on left side of page of other topics.
       
    Wire Size, AWG and Funny Numbers
    Electric Motor HP Ratings (and Other Secrets of the Universe) vs Gas
    Basic Motor Types: PMDC, BLDC, AC Induction, Synchronous and Series DC
    NEW PMAC 38 kW Liquid-Cooled 120V Motor (from Electric Motorsport)
    Axial vs Radial Flux: Simple as Pie. Or cake. Or Pancake. Motor.
    Conversion Table Reference: RapidTables
    Electric Motor Power (Really Simple) and HP Ratings
    Motor Starting Torque (Peak Stall Torque) and Motor Types

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#85 2018-03-31 18:46:03

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

http://www.emic-bg.org/files/Electric_M … Drives.pdf

Continuing to do research into how one can build motors and generators for the given applications of making things move. Battery research will come later as cost is the key to being able to do this on a little bit of money.

My homemade bicycle motor, version 1

The key to understanding motors and generators http://allianceorg.com/pdfs/Magnet_Tutorial_v85_1.pdf plus the creation of the magnets to make it all happen. The processing of ore to magnets are contained within the pages.

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#86 2018-04-01 09:15:21

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

Tire wheel hub motor design
http://lati-solar-car.wikispaces.com/fi … +Sheet.pdf

Sinjce we will need to make the insitu magnets I would look for materials in the remnant field areas for this.
How magnets are made
https://www.quora.com/How-does-one-make … nt-magnets

Something to make not of is that while the same design for a generator and a motor can be done the actual difference for 3 phase delta or wye wiring is a generator will use more magnets than coils of wire versus usually 4 to 3 per phase while in a motor you will use less magnets than the coil count even for that same wiring. For a generator we need rectifing diodes to change the AC to DC while for the motor we will pulse the phase winding in sequence to make the motor move.

http://www.completepowerelectronics.com … ldc-motor/

https://www.digikey.com/en/articles/tec … or-control

BLDC motor stator is the same as what would be the generator with the amount of magnets changing.
article-2013march-introduction-to-brushless-dc-fig1.jpg

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#87 2018-04-01 15:33:01

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

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#88 2018-04-02 19:14:44

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

Here is a page to help with coil to magnet counts and how many turns will be in the coils to create and\ approximate voltage output.
Winding Scheme Calculator

Coil Inductance Calculator

http://chemandy.com/calculators/round-w … ulator.htm

Some more great images of the stator

http://www.diyelectriccar.com/forums/

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#89 2018-04-07 08:39:32

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

So You Want to Build an Electric Car

If when designing the motor the choices are for in the hub or on the end of an transaxle or axle and then again at the end of the transmission.

http://www.ebikeschool.com/geared-hub-m … ub-motors/
Gearless (direct drive) hub motors
inside-a-gearless-hub-motor.jpg?resize=300%2C224

gut of a small motor for a hub
razor-hub-motor.jpg

Geared hub motors
planetary-gear-gif1.gif?resize=256%2C170

For those that do not want to build here is a site that show examples for what the pricing of what can be https://www.diyebikestore.com/c/hub-motor_0388 not endorsing just information.

Motors can also be belt or chain drive to the wheel as well as geared.
https://hackaday.com/2009/10/18/1480w-s … ad-trauma/
1480w-scooter-motor.jpg?w=470

So many choices of how to make motion need to now study and research motor controllers

http://kellycontroller.com/Permanent-Ma … roller.php

it appears voltage source is a value that is fixed for the purchase and design

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#90 2018-04-07 11:30:22

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

One of the main objectives with the permanent magnet design is they would require no brushes for the motor to operate. Another is how to cool the motor and how much torque willbe required for the speed that you will want to move at. The design images from post 99 are magnets on the outside while this one will be on the inside of the motor which makes it good for an axle design.
45KW Bushless motor design
Brushless-motor60Kw.jpg

Motor controllers are inAC or DC type of which the permanent magnet is sort of a cross between both as its a pulsed DC which makes it move.

http://www.instructables.com/id/200kW-A … ctric-Car/

http://www.instructables.com/id/Homemad … lectric-C/

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#92 2018-04-09 19:39:08

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

Was reading today about speed and mass of a vehicle in that the power coming form the battery are and is the factor to which controls this to a greater level. The voltage as it rises will make it such that we can go faster under a set mass and that the torque for a greater mass drives the current load required from a battery up. Its this combination and the watt hour rating in ampere hours that matter for the usefill time period of use of the battery pack design.

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#93 2018-04-16 21:23:07

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

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#94 2018-04-21 11:58:25

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

Electric Car Motors: Horsepower

Weight to power ratio:
    When you're selecting electric car motors, 8hp (continuous) for every thousand pounds of finished, loaded vehicle weight. That means figure in the car's curb weight - along with the load of batteries, corn-fed American passengers, and the trunk full of camping equipment. Seth sez: "More horsepower is required for higher speeds, heavier vehicles, and steeper terrains."
Electric Motor Rating:
    They're rated at their maximum efficiency, which is designated "continuous", although they are capable of short bursts of power 2-4 times greater than their continuous rating (without damaging the motor), called "peak".
Voltage and Horsepower:
    The horsepower goes up with the voltage. Motors are rated, not only "continuous" and "peak", but at a given voltage, as well. There's no way to figure an EV motor's horsepower without knowing the voltage of the system.
Over- and Under-powered Motors:
    No worries if you get a motor that's a little oversized for your car, that's what the controller is for. The tradeoff is that you're wasting weight on motor that you could be spending on batteries. If you get a motor that's a little undersized, though, the challenge is keeping it cool enough.
The Need for Speed:
    If you like to drive on the freeway, you'll need more horsepower per pound. Seth says it takes four times the horsepower to go 70mph than it does to go 35mph.

Air Drag Coefficients and Frontal Area Calculation: Coefficient of Drag
http://www.wallaceracing.com/Calculate% … 0Speed.php

https://en.wikipedia.org/wiki/Power-to-weight_ratio

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#95 2018-04-22 07:36:10

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 11,375

Re: Mars Cart

Pancake flat motrors and generators

Coreless Axial Flux Motors

angled_winding_all_turns.jpg

Another very interesting design

Less Epic Axial Flux motor

LEAF_exploded.jpg

I have seen a number of builds using metals and even wood to make up various parts of the generators and motors in permanent magnet builds.

http://library.uniteddiversity.coop/Ene … manual.pdf

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