RE: Design for a Cause - The Ultimate Smart Trike Design Blog 2 of 4

mcb1 — Sun, 14 Oct 2018 11:52:34 GMT

The first principle of building assistive tech is "Do No Harm!"

Good thought.

Obviously you have the brain box to go, but what about detecting pedal movement first before it applies motor power.

You'd only have to pedal one revolution which assures the system both feet are on the pedals.

Blog 4 shows you've done exactly that ... good solution.

Your 650w motor might be overkill, which also could be part of the other issues.

Australia only allows 200w motors or 250w if they are pedal assisted.

(There is a discussion here which raises some valid points http://dillengerelectricbikes.com.au/blog/electric-bikes-and-the-law.html )

You may also be able to apply a throttle/speed reduction in the turns, or simply physically limit the turning ability.

Dual Piston Brake caliper and hydraulic actuator (as found on ATVs)

You'll also need to be careful about the type of brake system you add.

Many of the hydraulic units actually drag the pads, which is not desirable for this application.

You could look at some of the downhill mountain bike versions.

The larger the diameter of the rotor, the greater the stopping force.

(something people forget when adding larger wheels to a vehicle)

I did see that you're cutting motor power when the brakes are on, pity regen braking isn't available, or maybe you can dump a rectifier and charging cct across the motor when brakes are only just on??

Lower the Center of Gravity: on our Raising Awesome Channel, we will weld in the battery brackets that will locate the batteries under the trike. This will take the center of gravity as low as it can go and move it under the rider for added stability.

I was wondering if there was room in front of the rear axle and slightly below the centreline to mount one battery each side.

The further out you place these the more stable it will be. You're still stuck with a single battery but this could be at the same height at the rear.

Mark

RE: Design for a Cause - The Ultimate Smart Trike Design Blog 2 of 4

dixonselvan — Fri, 10 Aug 2018 04:26:48 GMT

Congratulations [mention:5517e1b11f91409081f704d23d850071:e9ed411860ed4f2ba0265705b8793d05] and Connor on making it upto a test drive and good luck for your smarts.

I watched half of the video here https://www.element14.com/community/videos/26430/l/ultimate-smart-trike-blog-2 as you had mentioned you have some technical difficulties uploading the rest half. That half was really nice to watch as you guys build the Trike.

May I suggest you to add a bar horizontally, welded in the front guard of rear wheel from one to other for the below? This way it will block your legs from traveling into the wheels. But keep an eye that it will not affect the movement while we pedal.

You could easily run over your legs with the back wheels if you accidently hit the throttle when stopped with your feet down.

For the below try adding / spreading the weight in the back from the Center that way you will lower the Center of gravity of trike in tight turns.

The trike has to take wide turns. Tight turns that you would do on a bike will actually cause it to go up on one wheel in the back. This is not a problem for the paved rail trails we ride, but would be bad for a crowded beach

[View:/resized-image/__size/1061x900/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-76e2cd22-08fc-4c62-9abc-1090675231b0/contentimage_5F00_189045.jpg:1061:900]