Comments by "Mikko Rantalainen" (@MikkoRantalainen) on "Tom Stanton" channel.

15:00 How about using an arm from the actuator to brake handle? It seems that the rope hack added so much stretching that it causes extra lag to the system. Another way would be to use actuator to move pivot point of the brake handle instead of moving the handle itself. With adequate movement of the pivot point, the same handle pressure can result in different hydraulic pressure. For example replacing the brake handle pivot bolt with a part that has off-center middle section it could move the handle pivot point a lot with only 180 degree rotation from the actuator (you obviously cannot ever get more than 180 degree range from actuator with this setup, note that you could also get faster on/off cycle with running actuator full speed in one direction).
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@__WJK__ Yes, birds are basically allergic to gases that get emitted from Teflon if you heat it above 280 °C. As long as you keep the temperature below that limit, Teflon is completely safe even for birds. And it's safe for humans in all cases but you should keep any Teflon items below 260 °C anyway or it will degrade over time.
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How about using hub motors with a couple of 1 F supercapacitors (e.g. ones designed for car audio use)? With good enough ESC that should be able to do pretty good regen and instant power output with very little mechanical losses. For example, 3 F worth of capasitors and 50 V voltage, your power storage is about 3700 J which should be enough to stop and re-accelerate a bicycle. Supercapacitors should be a lot lighter than Li-ion battery pack so it should improve the overall handling a lot.
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Great video! If you could do this without causing lots of heat, it would be very nice way to create a clutch. As it currently works, it's just very low efficiency power transmission system.
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Since the coils cannot switch on/off instantly, have you tested advancing the timing for the coil switching? That would require using more complex timing than just using the sensor at the coil but should allow pushing more power to the launched object. For example, use a coil specific delay (the delay should be less and less as the speed increases) and using the sensor one before the actual coil? If you had the sensor after the coil, maybe just reversing the coils to have the sensor before the coil would allow enough advance?
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Do you have any idea about the efficiency of belt + 3D printed pulley? That pulley system looks like it could be eating majority of the generated torque alone. Maybe you could use some factory made metallic gears intented for high power RC cars instead?
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13:30 How about braking by pedaling backwards rapidly?
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@TomStantonEngineering Oh, the forces to pedals didn't appear that strong in the video but that makes sense. It would have been worth mentioning in the video.
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1:30 How about using another pair of magnets, one at the end of the axle and another opposing one in the post? That would prevent the axle from moving towards the post and wouldn't require any contact. Also, it would be interesting to charge the flywheel with electricity but that would require some kind of syncronization method for the coils to be able to push more speed to flywheel.
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I think you should have used e.g. potentiometer to create very quick angle adjustment. Basically you'd need some kind of input control to adjust the angle limit. With two controls you could have angle setting and steepness setting (basically how close to limit you can go without the servo doing nothing and then applying lot of servo movement even with a slight increase in angle). I would guess having quick adjustment would be good enough and you don't need more sophisticated sensors.
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Describing Curiosity Stream as Netflix for geeks was pretty clever indeed!
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Using the syringe as a pressure controller was clever but replacing two gears with a simple wire with two 90 angles was genious! I think replacing the rubber diaphram with a latex sheet (like in surgical gloves) should improve the efficiency even more. You may still need rubber ring as gasket material unless your surfaces are really flat. And the surfaces that the latex sheet touches cannot have any sharp corners or surfaces.
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Take a hint from real airplanes: have a pre-flight checklist which includes checking full range control surface movement before starting the engine.
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I'd love to use Opera (and I used to use it daily) but I stopped using it years ago when they broke the native window titlebars on Linux and haven't fixed it since. The Google Chrome supports using native window titlebars and the most recent version also allows using native OS theme for the UI so I'm using it instead of Opera nowadays. (My window manager has features that Opera cannot emulate correctly and breaking the native window handling disables those features for Opera windows. This is such a bad downgrade in window handling that I cannot stand using Opera anymore.)
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Couldn't you use 3D printed wing surface as a mold for carbon fiber mat and thin coat of epoxy? Maybe some wax in between so that you can get the mat of the mold after epoxy has set. That should result in smooth and strong surface. Of course, you would still need wing ribs to connect the carbon fiber wing surface to the spars.
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For a very slippery test surface, try dry sand on one year old dry asphalt on downhill. If you can get ABS to work on that, it will be good.
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8:20 the actuator rotates around then handle bar which obviously prevents the system working as designed.
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@vennox1598 As I wrote, "it should be enough to stop and re-accelerate a bicycle". I totally agree that supercapacitors are not energy storage method in general but for stop and go solutions that could be exactly what you're looking for if you are willing to get the energy for continuing continous movement from somewhere else.
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Great project! I think you should imitate real world glider planes which have much narrower but longer wings to increase lift. I would also guess your film was simply shrank too much which caused ribs at the wing tips to bend (and also make the airfoil curved between the ribs). I would guess it's better to have the film ever so slightly too loose than to get shrink it so much the surface doesn't follow the designed form.
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11:30 Shut up and take my money already! I think this amount of regenerative braking is good already and with some intentional limits in output, you can have a bike that's great for environment with hills - it doesn't take off all the pedaling uphills but will help a lot and supercapacitor bank is much much lighther than full Li-on or LiPo or LiFe battery pack. Maybe if you find a high efficiency and high current DC-DC transformer that can pull the capacitors fully empty that's good enough already! I'd be interested in bike that is not fully battery powered but in practice helping to level hills.
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4:00 the code seemed to have "delay(10)". Why not constantly read the angle and adjust the servo?
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10:45 That airplane sledge was really clever! Nice design.
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3:30 At least car ABS systems use hall sensors and iron disk with slots to make sure getting dirt into the disk doesn't affect the behavior too much.
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How about instead of spike and plate at the end of spinning axle, you put one magnet at the end of the axle and another on the stand? When you orient both so that the poles are against each other, it should prevent the axle from moving to left and require no contact at all.
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9:40 So your power recovery efficiency is 50% and your power output efficiency is 50%. As a result, if you don't charge the spinning disk by pedaling it to full speed your total KERS efficiency is 50% * 50% = 25%. I guess a real KERS system for bicycles must use electricity instead because there you can create "infinite variable gearing" by using different strength magnetic field instead of direct coupling. If your parts can handle the forces and you don't mind shocks, you can improve the efficiency of this setup by using very heavy clutch which should result in less waste to friction of the brake disk surface.
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