News

  • Different way for lifting commercial airplane and jet fighter in the air

    Jet fighter is able to trickily maneuver upside down due to vectored thrust for lifting itself mainly in the air. However any commercial airplane can fly through lifting force on the airfoil wings based on Bernoulli's equation, but it will crash after flipping over. The force can lift Boeing 747 (almost 900,000 lbs) via a 260 feet long wings made of aluminum which can take care of all the stress including dead, live, environmental and other loads. It is amazing. Similarly, light aluminum can afford all the loading in a good design electric bicycle which is same as bridge truss shape....

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  • NBA players have amazing muscle and brains, how about torque and power in an ebike ?

    Muscular  players with good skill & ability win the basketball game. Similarly, we will  happily have both sufficient power and torque to ride bicycle around all terrains.  It is easy to understand that horsepower is a product of torque and revolution speed in a driving wheel. However  we need  a required torque on the wheel rim for going forward, regardless of force originated from same wheel hub or chain wheel at bottom of bracket on a bike. In a word, E-Bike rider can go uphill if there is adequate force and horsepower of the driving rim mainly, no matter what...

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  • What is the difference between an AC and DC motor

    ( 1.) The power for DC motor is battery, electric bicycle and EV should have DC motor for driving. In same way, AC and DC motors are operated by magnetic force from induced wiring or metal inside the device. However the control and construction are somehow difference. ( 2.) Mostly, AC motors perform some slips from full synchronous speed for certain loading in an industrial process. It provides simply electric appliance   for human and equipment protection. ( 3.) Some AC motors with more complicated electronic control system for variable process loading such as subway, high-speed train, air conditioner, industrial...

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  • Maintaining an EV is simpler than gasoline car, how about electric bike

    As we know, it is easier to have heat from mechanical, electrical, chemical energy. According to thermodynamics, there should be  more complex devices for transferring heat to be kinetic energy in reverse. Hundreds of parts in a car to integrate an auto machine for moving, there is still half heat waste through cooling & exhaust system. Compared to Internal Combustion Engine, EV is simple to get electricity from chemical energy efficiently based on electrochemical  process.  The parts and maintenance are less accordingly. All the industry products are assembled via modules mostly for effortless maintenance following from good system design in...

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  • Do you know why EPA estimates driving range in city is more than in highway for EV, while MPG of gasoline auto is less in city than in highway?

    It is a very interesting topic. You will know the reason, after understanding  the knowledge about kinetic energy, chemical energy, thermodynamics, electrical energy. Basically there is a nonzero threshold  operation in gasoline auto, however we can have zero output for Electric Vehicle during static motion in city to save energy. Also DC motor efficiency in EV is over 80 % and recover energy for the farther distance via chargeable device during running in city, while gasoline auto provides 40 % kinetic energy ultimately in highway. In city, gasoline auto gets lower energy efficient due to slower speed and have nonzero...

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  • Uphill ebike ride exhaust most kinetic energy

    From physics calculation, almost half motion energy is killed during 6% uphill e-bike riding at 15 mph. Although in theory, kinetic energy equaled to half mass and velocity squared, can be transferred to the equivalent potential energy (mass x gravitational acceleration x height), but energy consumption on flat road is some of kinetic energy only in ebike motion. It depends on tire, mechanical loss, air resistance relating to moving velocity, riding manner. On uphill path, a lot of kinetic energy will be converted to equivalent gravitational potential, and be wasted completely. It is better to ride light-weight ebike while go uphill...

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  • How feeding baby as ebike loop control

    Normally, babies may cue mom by crying, putting fingers in his or her mouth, or making sucking noises, when they seem hungry. If you're formula-feeding, you can easily monitor if your baby is getting enough to eat, but it should be a little trickier, while breastfeeding. Mom including her thinking helps newborn to complete total closed loop feeding work being similar to real PAS in ebike. Gradually, babies can have wonderful eating or sucking via their intelligence in brains after growing, then done each feeding cycle by themselves from staring hungry signal to sucking finish. Speed cadence PAS ebike performs simple open loop function...

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  • Why rider can't easily go uphill via so-called PAS on ebike

    You can comfortably ride an intelligent closed loop Pedal Assist System regarding pedal torque, but it is hard to get power smoothly for riding  on a so-called cadence sensor PAS Ebike. The DC motor on electric bike outputs power for riding by means of its original design performance like AC motor which is always same as full duty frequency as power supply plant, together with operating duty cycles provided in different ways described below. 1. Very smart closed loop controller has the appropriate duty signal for DC motor based on calculated torque requirement relating to sensing data. Therefore  you will feel very smoothly to...

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  • Additional feedforward control lets safety driving along mountain road

    While driving on I-5 between Redding and Eugene on sunny day, it is very beautiful scenery.  All should drive carefully  along this mountain road at raining night, although driving is a simple action as closed loop control. If we follow a commercial truck 1000 feet away to drive, it is easier to go through as we have his feedforward skill. The truck and local drivers are familiar with  this road, and have feed-forward control with basic closed loop on their minds around this I-5 terrains. Surely they can drive smoothly during raining night. We also have this feedforward concept to easily drive through...

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  • Could be Autopilot in electric bicycle?

    Definitely we can have cruise control in throttling operation like vehicle, but there will be never self-driving two-wheeled motorcycle, E-bike to be Autopilot. Appropriate system including adequate motor or engine power output, reasonable characteristic performance between torque and speed will let rider to target acceptable cruise speed in simple throttling operation. It is easy to understand the process  data like speed and its regulating ebike motor current, motorcycle gasoline flow play major roles together. While riding real PAS e-bike,  the pedaling force and motor output power together work well  through intelligent controller. Thus torque, horsepower, and good brain controller form a...

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