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Batman gadgets
Dr. Jay Maron


Batman gadgets
Dr. Jay Maron

Tesla Model S


Electric propulsion

Electric propulsion is better than gasoline propulsion in all categories except range. Electric motors are quiter, simpler, more powerful, and more flexible than gasoline motors and they can be put on anything. Examples include:

            Power   Max speed   Mass   Wheel
            kWatts     mph       kg    inch

Roller skate     .1    15         6      6
Kick scooter     .4    25         7      6
Bike            2      45        30     26
Car            40      85       300     24
Copter        120     100       400      -
The larger the wheel the larger the top speed.
Air drag

Cycling power

Air density      =  D  =  1.22 kg/meter3
Top speed        =  V
Drag coefficient =  C
Cross section    =  A
Drag parameter   =  K  =  ½ C A
Drag force       =  F  =  ½ C A D V2
Drag power       =  P  =  ½ C A D V3  =  K D V3  =  F V

Commercial vehicles

                         Mass      Battery  Battery  Battery  Power  Power  Flight  Price
                                   energy    mass                    /mass   time
                          kg       MJoule     kg      MJ/kg   kWatt  W/kg   minutes   $

Jetjat Nano     Drone        .011     .00160                  .0033   303      8      40
ByRobot Fighter Drone        .030     .0040                   .0067   222     10     120
XDrone Zepto    Drone        .082     .0067                   .0046    56     24      40
Walkera QRY100  Drone        .146     .0213    .0413   .52    .018    122     20     100
DJI Mavic Pro   Drone        .725     .157     .24     .65    .11     150     24    1000
DJI Phantom 4   Drone       1.38      .293     .426    .69    .17     126     28    1000
JYU Spider X    Drone       2.1       .360     .812    .44    .20      95     30     155
MD4-1000        Drone       2.65     1.039                    .20      74     88    2000
Walkera QRX800  Drone       3.9       .799    1.134    .70    .22      57     60    2700
AEE F100        Drone       6.0      1.598                    .38      63     70   58000
Ehang 184       Drone     200       51.8                    37.50     188     23  300000
Hammacher       Skate       6.4                               .10      16            700
Zero            Scooter     7.0       .899                    .45      64            500
Revelo          Bike       15        1.35                     .25      17
Lankeleishi     Bike       25.0      2.07     2.6      .80    .24      10            600
Seagull         Bike       26.3      2.25                    1.0       38           2000
Wolverine       Bike       38.6      8.64                    7.0      181          10450
Honey Badger    Bike       50        6.91     8.6      .80   8.0      160           
Mitsubishi MiEV Car      1080       58      201        .29  47         44          16300
Tesla S P85D    Car      2239      306      540        .57 568        254         115000
Barska TC1200   Flashlight   .41      .032     .45     .71    .015     37            120
Violet laser    Laser        .182     .009     .0152   .62    .0001      .55          20
RAVPower        Battery      .590     .414     .590    .70                            60
Samsung S5      Phone        .145     .039     .038   1.03
"Drone power" is the power to hover for drones and the maximum engine power for cars and bikes.

For non-electronic racing bikes, the rules state a minimum mass of 6.8 kg. This is an effective minimum mass for an electric bike.


Energy and power

Energy          =  E  =  F X  Joules
Time            =  T          seconds
Power           =  P  =  E/T  Watts
Mass            =  M          kilograms
Energy/Mass     =  e  =  E/M  Joules/kilogram
Power/Mass      =  p  =  P/M  Watts/kilogram

Energy/Mass and Power/Mass

Tesla Roadster

                    Energy/Mass   Power/mass  Density   Energy/$
                     MJoule/kg     Watt/kg              MJoule/$

Antimatter           90000000000
Fusion bomb            250000000                                  Max for d+t fusion
Fission bomb            83000000                                  Max for a uranium bomb
Nuclear battery, Pu-238  2265000          10             7.6      88 year half life
Nuclear battery, Sr-90    589000          10            59        29 year half life
Hydrogen ( 0 carbons)        141.8              .07
Methane  ( 1 carbon )         55.5              .42               Natural gas
Ethane   ( 2 carbons)         51.9              .54
Propane  ( 3 carbons)         50.4              .60
Butane   ( 4 carbons)         49.5              .60
Octane   ( 8 carbons)         47.8              .70
Kerosene (12 carbons)         46                .75
Diesel   (16 carbons)         46                .77
Oil      (36 carbons)         46                .8
Fat      (20 carbons)         37                .9                9 Calories/gram
Pure carbon                   32.8             2.0
Coal                          32                .8
Ethanol  ( 2 carbons)         29                .79               7 Calories/gram
Wood                          22                .6
Sugar    ( 6 carbons)         17               1.54               4 Calories/gram
Protein                       17               1.06               4 Calories/gram
Plastic explosive              8.0             1.91               HMX
Smokeless powder               5.2             1.23               Modern gunpowder
TNT                            4.7             1.65
Black powder                   2.6             1.7                Medieval gunpowder
Phosphocreatine                 .137                              Recharges ATP
ATP                             .057           1.04               Adenosine triphosphate
Battery, aluminum-air          4.68      130
Battery, Li-S                  1.44      670
Battery, Li-ion                 .8      1600              .007
Battery, Li-polymer             .6      4000
Battery, Alkaline               .4
Battery, Lead acid              .15      150
Lithium supercapacitor          .054   15000
Supercapacitor                  .016    8000              .00005
Aluminum capacitor              .010   10000              .0001
Spring                          .0003
Human                                     20
Solar cell, space station                 77
Fuel cell                               1000
Gasoline engine                         8200
Electric motor                         10000
Jet engine                             10000
Rocket engine                        3200000
Batteries take an hour to recharge and capacitors charge instantly. Batteries can only be charged 1000 times whereas capacitors can be charged an infinite number of times. All batteries are rechargeable except the aluminum air battery.

The energy cost to convert water to hydrogen and oxygen is 13.16 MJ/kg. If hydrogen and oxygen are reacted to produce one kg of water, the energy produced is equivalent to a 1 kg mass moving at 5.13 km/s.


Flight time

The flight time of a drone is determined by:
*) The battery energy/mass.
*) The power/mass required to hover.
*) The ratio of the battery mass to the drone mass.

Typical parameters for a drone are:

Drone mass         =  M          =  1.0 kg
Battery mass       =  Mbat        =  .5 kg           (The battery is the most vital component)
Battery energy     =  E          =  .38 MJoules
Battery energy/mass=  ebat= E/Mbat=  .75 MJoules/kg   (Upper range for lithium batteries)
Drone energy/mass  =  e  =  E/M  =  .38 MJoules/kg
Drone power/mass   =  p  =  P/M  =   60 Watts/kg    (Practical minimum to hover. Independent of mass)
Drone power        =  P  =  p M  =   60 Watts       (Power required to hover)
Flight time        =  T  =  E/P  = 6250 seconds  =  104 minutes
The flight time in terms of component parameters is
T  =  (ebat/p) * (Mbat/M)

Drone power system

One has to choose a wise balance for the masses of the motor, battery, fuselage, and payload. The properties of the electrical components are:

                    Energy/Mass  Power/mass  Energy/$  Power/$  $/Mass
                     MJoule/kg    kWatt/kg   MJoule/$  kWatt/$   $/kg

Electric motor          -         10.0        -        .062     160
Lithium-ion battery     .75        1.5        .009     .0142    106
Lithium supercapacitor  .008       8          .0010    .09       90
Aluminum capacitor      .0011    100
If the battery and motor have equal power then the battery has a larger mass than the motor.
Mass of motor            =  Mmot
Mass of battery          =  Mbat
Power                    =  P             (Same for both the motor and the battery)
Power/mass of motor      =  pmot  =  P/Mmot  =   8.0 kWatt/kg
Power/mass of battery    =  pbat  =  P/Mbat  =   1.5 kWatt/kg
Battery mass / Motor mass=  R    =Mbat/Mmot  =  pmot/pbat  =  5.3
The "sports prowess" of a drone is the drone power divided by the minimum hover power. To fly, this number must be larger than 1.
Drone mass               =  Mdro
Motor mass               =  Mmot
Motor power/mass         =  pmot =  8000 Watts/kg
Hover minimum power/mass =  phov =    60 Watts/kg
Drone power              =  Pdro =  pmot Mmot
Hover minimum power      =  Phov =  phov Mdro
Sports prowess           =  S   =  Pdro/Phov  =  (pmot/phov) * (Mmot/Mdro)  =  80 Mmot/Mdro
If S=1 then Mmot/Mdro = 1/80 and the motor constitutes a negligible fraction of the drone mass. One can afford to increase the motor mass to make a sports drone with S >> 1.

If the motor and battery generate equal power then the sports prowess is

S  =  (pbat/phov) * (Mbat/Mdro)  =  25 Mbat/Mdro
If Mbat/Mdro = ½ then S=12.5, well above the minimum required to hover.

Suppose a drone has a mass of 1 kg. A squash racquet can have a mass of as little as .12 kg. The fuselage mass can be much less than this because a drone doesn't need to be as tough as a squash racquet, hence the fuselage mass is negligible compared to the drone mass. An example configuration is:

              kg

Battery       .5
Motors        .1   To match the battery and motor power, set motor mass / battery mass = 1/5
Rotors       <.05
Fuselage      .1
Camera        .3
Drone total  1.0
Supercapacitors can generate a larger power/mass than batteries and are useful for extreme bursts of power, however their energy density is low compared to batteries and so the burst is short. If the supercapacitor and battery have equal power then
Battery power/mass         =  pbat  =  1.5 kWatts/kg
Supercapacitor power/mass  =  psup  =  8.0 kWatts/kg
Battery power              =  P
Battery mass               =  Mbat  =  P / pbat
Supercapacitor mass        =  Msup  =  P / psup
Supercapacitor/Battery mass=  R     =Msup/ Mbat  =  pbat/psup  =  .19
The supercapacitor is substantially ligher than the battery. By adding a lightweight supercapacitor you can double the power. Since drones already have abundant power, the added mass of the supercapacitor usually makes this not worth it.

If a battery and an aluminum capacitor have equal powers,

Aluminum capacitor mass  /  Battery mass  =  .015
If a battery or supercapacitor is operating at full power then the time required to expend all the energy is
Mass          =  M
Energy        =  E
Power         =  P
Energy/Mass   =  e  =  E/M
Power/Mass    =  p  =  P/M
Discharge time=  T  =  E/P  =  e/p

                     Energy/Mass  Power/Mass   Discharge time   Mass
                      MJoule/kg    kWatt/kg       seconds        kg

Lithium battery         .75          1.5          500           1.0
Supercapacitor          .008         8.0            1.0          .19
Aluminum capacitor      .0011      100               .011        .015
"Mass" is the mass required to provide equal power as a lithium battery of equal mass. 0;256;0c
Energy

Energies in MJoules = 106 Joules

1 Watt hour                             .0036      1 Watt * 3600 seconds
1 food calorie                          .0042
Sprinting person                        .004       (80 kg moving at 10 m/s)
Battery, lithium, AAA                   .0047
Battery, lithium, AA                    .0107
Battery, iPhone                         .018       ( 5 Watt hours)
Battery, laptop                         .180       (50 Watt hours)
1 kg of Lithium battery                1.0
1 kg of TNT                            4.2
1 kg of sugar                         20     =  5000 Food Calories
1 kg of protein                       20     =  5000 Food Calories
1 kg of alcohol                       25     =  7000 Food Calories
1 kg of fat                           38     =  9000 Food Calories
1 kg of gasoline                      48     = 13000 Food Calories
Uranium fission bomb (Little boy)    7⋅107    = 16 kilotons of TNT
Plutonium fission bomb (Trinity)     8⋅107    = 20 kilotons of TNT
Uranium fission bomb (Fat man)       9⋅107    = 22 kilotons of TNT
Fusion bomb                          4⋅1010   = 10 megatons of TNT
World energy production in 1 year    6⋅1014


                 Energy    Mass   Velocity
                 (Joule)   (kg)    (m/s)

Ping pong ball        2.2    .0027     40
Squash ball          43      .024      60
Golf ball           230      .046     100
Tennis ball         104      .058      60
Baseball ball       116      .146      40
Soccer ball         778      .432      60
Bullet, 9 mm        338      .0065    323
Cannonball      1900000    14         518     220 mm diameter
Human sprint       4000    80          10
Car, freeway     540000  1200          30
Forms of energy:
Distance         =  X          meters
Force            =  F          Newtons
Mass             =  M          kg
Velocity         =  V          meters/second
Gravity constant =  g  =  9.8  meters/second2
Pressure         =  P          Pascals
Volume           =  U          meters3
Mechanical energy=  Ew =  F X  Joules
Gravity energy   =  Eg =  MgX  Joules    (X = height above ground)
Kinetic energy   =  Ek =  ½MV2 Joules
Pressure energy  =  Ep =  P U  Joules

Power
                         Watts

Human cell                 10-12
Laptop computer            10
Human brain                20
Incandescent Light bulb    60
Human at rest             100
1 horsepower              746
Strenuous exercise       1000
Maximum human power      1600
World power per person   2500
Tesla S Ludicrous      397000       532 horsepower
Wind turbine               1⋅106
Blue whale               2.5⋅106
Boeing 747               1.4⋅108
Hoover Dam               2.1⋅109
U.S. power consumption   3.4⋅1012
World power consumption  1.5⋅1013
Earth geologic heat      4.4⋅1013
World photosynthesis     7.5⋅1013
Earth solar power        1.7⋅1017    Total solar power falling on the Earth

Fuel

Most fuels are combinations of carbon, hydrogen, and oxygen, and are collectively called "hydrocarbons".

Black: Carbon        White: Hydrogen        Red: Oxygen

Methane (Natural gas)
Ethane
Propane
Butane (Lighter fluid)
Octane (gasoline)
Dodecane (Kerosene)

Hexadecane (Diesel)
Palmitic acid (fat)
Ethanol (alcohol)

Glucose (sugar)
Fructose (sugar)
Galactose (sugar)
Lactose = Glucose + Galactose
Starch (sugar chain)
Leucine (amino acid)

ATP (Adenosine triphosphate)
Phosphocreatine
Nitrocellulose (smokeless powder)
TNT
HMX (plastic explosive)

Lignin (wood)
Coal

Medival-style black powder
Modern smokeless powder
Capacitor
Lithium-ion battery
Nuclear battery (radioactive plutonium-238)
Nuclear fission
Nuclear fusion
Antimatter


Power and energy
              Energy/Mass   Power/mass   Energy/$
               MJoule/kg     Watt/kg     MJoule/$

Gasoline            47                    60
Fat                 37                     1.0      Cheese
Ethanol             29                      .6      Vodka
Sugar               17                     6        Cane sugar
Plastic explosive    8.0    600000                  HMX
Modern gunpowder     5.2     10000                  Smokeless powder
Medieval gunpowder   2.6     50000                  Black powder
Battery, aluminum    4.6       130                  Not rechargeable
Battery, lithium      .9      1500          .010    Rechargeable, 1000 cycles max
Battery, alkaline     .4                            Rechargeable, 1000 cycles max
Battery, lead acid    .15      150                  Rechargeable, 1000 cycles max
Supercapacitor        .05    15000          .00005  Rechargeable, infinite cycles
Aluminum capacitor    .010   10000          .0001   Rechargeable, infinite cycles
Human                           20
Solar cell                      20
Gasoline engine               8000
Electric motor                8000

Lasers
       Power    $  Diameter  Length  Beam  Beam
       Watts          mm       mm    mrad   mm

Violet   .075   70   16.5     170     .5    4   wicked nano
Violet   .1     10   16.2                       lasers-pointers
Violet   .2     20   20       112               laserpointerpro
Violet   .5     30   24       148               laserpointerpro
Violet  1.0    100   24       180               laserpointerpro
Blue     .2     65                              freemascot.com
Blue    1.0     70                              freemascot.com


Color   Wavelength (nm)

Violet    405
Blue      445
Green     532
Yellow    589
Red       635

Flashlights
                   $  Lumens  Diameter  Mass    Lumens per
                                inch    ounce     inch2

Thrunite Ti4T       36   300    .55               1260
Thrunite Ti4        24   252    .55
ThorFire PF4        20   210    .6
Nitecore MT06       23   165    .55
Revtronic pocket    14   105    .6
Thrunite Archer 2A  36   500    .87     2.1        840
Revtronic 650       35   650   1.0
Fenix UC35          90   960   1.0
Barska TC1200      106  1200   1.0                1530
Fenix TK16          92  1000   1.3
Streamlight HL3     78  1100   1.6      7.1
Litecore TM03      158  2800   1.6                1390

MicroSD memory

Sandisk microsd cards on Amazon.com

GigaBytes   $

  32       13
  64       25
 128       45
 256      160

Laptops
                $  RAM  Drive  Size Thick CPUs GHz    Pixels   Pounds  Op

Asus T100HA     183   4    64  10.1   .7   4  1.4     1280  800  2.2  W10 Newegg  Detach
Asus T100HA     220   4    64  10.1   .7   4  1.4     1280  800  2.2  W10 Amazon  Detach
Asus T100HA     260   4    64  10.1   .7   4  1.4     1280  800  2.2  W10 Shopamerica
Asus T100TAF
Asus T101HA     300   4   128  10.1   .74     1.4                     W10 Adorama Detach
Asus T102HA     390   4   128  10.1        4  ?       1280  800  1.7  W10
Asus E200HA     200   4    32  11.5   .7   4  1.4     1366  768  2.2  W10 Amazon
Asus TP200SA    250   4    64  11.6   .73                             W10         Convert
Asus T200SA     350   4    64  11.6   .73  4  1.6                     W10 Asus
Asus TP201SA                   11.6

HP 11-y020wm    240   4    32   ?    thin     1.6                     W10 Amazon refurb
Lenovo x120e    140   4+4 128  11.6  brick    1.5     1366  768       W10 Newegg
Toshiba         210   4   128  11.6        4  2.7                         Amazon
Lenovo N22      194   4    64  11.6   .9   2  1.6     1366  768  2.7      Amazon
HP Elitebook    320   8   128  11.6               3i5                     Best Buy

HP 2740P        102   4    64  12.1           2.5  i5                     Newegg
HP Elitebook    210   8   120  12.1  1.1      2.1                2.6      Amazon
Asus Zenbook 3 1100  16  1024  12.5   .46     2.0                         Asus UX390UA

Dell Latitude   205   8   128  12.5           2.7                         Amazon
HP Elitebook    252   8   256  12.5           2.5  i5                     Newegg
Dell Latitude   350  16   256  12.5        2  2.5 2i5 1366  768  3.2      Best Buy
Dell Latitude   380  16   256  12.5               3i5                     Best Buy

Dell Latitude   303   8   240  13.3               2i5                     Best Buy
Dell Latitude   407  16   256  13.3               3i5                     Best Buy

Asus UX360CA    745   8   512  13.3   .54    M6Y75               2.9  W10
Asus UX303UA    750   8   256  13.3   .8   2  2.3
Asus UX305CA    730   8   512  13.3   .5              1920 1080  2.6  W10
Asus UX306UA   1000  16   512  13.3                              2.9  W10
Asus UX305UA          8   512  13.3   .63    i7 6500U 1920 1080  2.9  W10
Asus UX303UB   1050  16   512  13.3   .76
*: ebay
Metal
      Conductivity   Melt   Hardness  Hardness  Stiffness  Strength  Density  Price/kg
      MAmps/Volt/m  Kelvin    Mohs      GPa        GPa       GPa                $/kg

Silver    63.0       1235     2.5       .24        83        .17      10.5       590
Copper    59.6       1358     3         .87        30        .21       9.1         6
Gold      45.2       1337     2.5       .24        78        .12      19.3     24000
Aluminum  35.0        933     2.8       .24        70        .05       2.7         2
Beryllium 25         1560     5.5       .6        287        .45       1.85      850
Magnesium 23          923     2.5       .26        45        .22       1.74        3
Iridium   21.2       2917     6.5      1.67       528       1.32      22.6     13000
Tungsten  18.9       3695     7.5      2.57       441       1.51      19.2        50
Zinc      16.9        693     2.5       .41       108        .2        7.1         2
Cadmium   12.5        594     2.0       .20        50        .078      8.6         2
Indium    11.9        430     1.2       .009       11        .004      7.3       750
Tin        8.3        505     1.5       .005       47        .20                  22
Osmium                        7.0

Wire gauges
Gauge  Diameter  Continuous  10 second  1 second  32 ms    Resistance
          mm      current    current    current   current
                  Ampere     Ampere     Ampere    Ampere   mOhm/meter
 
 0        8.3      125        1900      16000     91000       .32
 2        6.5       95        1300      10200     57000       .51
 4        5.2       70         946       6400     36000       .82
 6        4.1       55         668       4000     23000      1.30
12        2.0       20         235       1000      5600      5.2
18        1.02      10          83        250      1400     21.0
24         .51       3.5        29         62       348     84
30         .255       .86       10         15        86    339
36         .127       .18        4         10        22   1361
40         .080                  1          1.5       8   3441

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