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Innovation Corporate since 1991
  • External Hardware Watchdog.

    Hey, are you in some way not exchanging the "hang" of the Arduino with the "hang" of the Tinker board? I mean - you are maybe reducing the statistics by a factor - but - replacing one computer with another computer rarely works. Would it not be possible instead, to create a physical, analogue watchdog timer which cannot fail (unless physically wire-wise disconnected), due to that there is no digital stuff in it? My thought was to create a super primitive logic which will see you having to maintain the voltage of an output at a certain level similar to the dead-man button for a train driver. So, if you put a capacitor from GND connecting via a resistor to ie. D4 (output), and then via another resistor to VCC, then you toggle the D4 forth and back - and then you monitor …

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    Hey, are you in some way not exchanging the "hang" of the Arduino with the "hang" of the Tinker board? I mean - you are maybe reducing the statistics by a factor - but - replacing one computer with another computer rarely works. Would it not be possible instead, to create a physical, analogue watchdog timer which cannot fail (unless physically wire-wise disconnected), due to that there is no digital stuff in it? My thought was to create a super primitive logic which will see you having to maintain the voltage of an output at a certain level similar to the dead-man button for a train driver. So, if you put a capacitor from GND connecting via a resistor to ie. D4 (output), and then via another resistor to VCC, then you toggle the D4 forth and back - and then you monitor the voltage on the capacitor - and if it goes to 0 (as the D4 has got stuck at 0) or if it goes to 1 (as the D4 has got stuck at 1), or goes to 1 as the D4 has got into Tri-state (disconnected), then the logic thereafter will reset the Arduino. We have the same problem as you - we are ALSO super talented - and have the same problem with seemingly random hanging of the Arduino boards.What are your thoughts?

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  • The Pandemic Ventilator

    The world may need 2 million+ ventilators.. The existing industry cannot ramp up this fast :-( Email me at ds@rain.yt and copy in the history of our conversation and let's start. We do not do Facebook.

    Email me at ds@rain.yt and copy in the history of our conversation and let's start. We do not do Facebook.

    That's exactly our approach. Kudos. We are using simple means which can be evaluated by normal people, not experts. Where a car mechanic can repair it!!! We may face situations where we will have normal people operating these based on very simple guidelines. So simple, safe, sustainable, solid and secure machines ...

    Well. We cannot get 50000 of these plc programmed and delivered within weeks, so, we do not have that option. While the plc may be stable, software is not. Programming a workable critical mission software even on a plc which responds correctly to a range of events, even in a multi event setting is not something done in just a few months. Imagine now making updates to these machines once distributed ?

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  • The Pandemic Ventilator

    I have seen many an Arduino halt or lock, or start executing from funny places in the software. Software is inherently unstable, in the Arduino case also due to its sensitivity to electric pulses/sparks/electromagnetic disturbance. I would therefore use an NE555 or similar timing circuit, such as to avoid sudden malfunctions. An Arduino could be made with an external (NE555?) timing device as a watch-dog timer - but again - the more equipment, the more parts can fail. My thought is to remove the valves, again due to that these too fail. Therefore I would use a bellow, with a fixed weight on top (adjustable along a stick) (see image). I would therefore raise the top wood, which is hinged at the right hand side - by use of the motor - and then the weight on top thereof to push the air into …

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    I have seen many an Arduino halt or lock, or start executing from funny places in the software. Software is inherently unstable, in the Arduino case also due to its sensitivity to electric pulses/sparks/electromagnetic disturbance. I would therefore use an NE555 or similar timing circuit, such as to avoid sudden malfunctions. An Arduino could be made with an external (NE555?) timing device as a watch-dog timer - but again - the more equipment, the more parts can fail. My thought is to remove the valves, again due to that these too fail. Therefore I would use a bellow, with a fixed weight on top (adjustable along a stick) (see image). I would therefore raise the top wood, which is hinged at the right hand side - by use of the motor - and then the weight on top thereof to push the air into the lungs. The two red valves would be gravity-held valves, which are made of simple rubber and hinged in one side. (Metal hinge plus rubber to tighten). All in all, I would make a primitive - absolutely primitive - solution - such as to ensure that as few components as possible can fail. We are having problems finding out how to make a bellow. (The black thing): We are using one of these ventilation/air tubes - but would like to know if there is any bellow type or style or technology which just works?

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  • The Pandemic Ventilator

    Dear Ibonavino, I would not put anything which can lock or get spoiled. I would really keep it simple. Stepper motor - how about if it gets stuck? The tubes ought being big, so that the air-speed is low. (large volume, low air speed)On air pump, I propose a permanent weight, which is being lifted and released to pump air into the patient.

    Dear Everybody. This is a great thing to do, and in the current COVID-19 situation, it can be acceptable with a DIY version. HOWEVER: I would, as a pretty experienced constructor of equipment do the following changes: 1) I would remove all the valves. 2) I would use a 12 volt motor from a wiper from a car. These NEVER EVER fail. They continue working, no matter what. 3) I would use a big car battery - or truck battery - 200 Ah - to ensure that power is available even during "power breaks".4) I would put a car charger to charge - and a power supply supplying the car charger. This to ensure that battery would indeed be maintained well, and not suddenly and invisibly, lose charge capacity - rendering a patient dead when power goes (and everybody thinks that the ventilator of course…

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    Dear Everybody. This is a great thing to do, and in the current COVID-19 situation, it can be acceptable with a DIY version. HOWEVER: I would, as a pretty experienced constructor of equipment do the following changes: 1) I would remove all the valves. 2) I would use a 12 volt motor from a wiper from a car. These NEVER EVER fail. They continue working, no matter what. 3) I would use a big car battery - or truck battery - 200 Ah - to ensure that power is available even during "power breaks".4) I would put a car charger to charge - and a power supply supplying the car charger. This to ensure that battery would indeed be maintained well, and not suddenly and invisibly, lose charge capacity - rendering a patient dead when power goes (and everybody thinks that the ventilator of course continues.5) I would equip the system (for use in 3rd world countries) - with a set of pedals and a bike-seat, for manual use, in case everything else fails.6) I would make the "in-ventilation" be controlled by a permanent weight, adjusted such that it provides proper inflation - I would guess some 0.05 kg/cm² would be OK as air pressure 7) I would use the wiper motor to lift the permanent weight, and would let the weight itself provide the air-pressure for the patient to breathe in via an air-container where the weight is put on top (for air pressure). The permanent weight should be adjusted such that the patient feel comfortable.8) I would by all means avoid any computer if I in any way could. They fail... (ie. a mobile phone coming too near, hardware malfunction etc.9) I would regulate the breathe in and breathe out periods with a very primitive electronic circuit, ie. a NE555 timer - and would make the breathe in drive for the motor with variable power (PWM control of the wiper motor) - The regulation would be separate in terms of 3 factors: 9.A) The time between letting go of pressure and applying pressure again. 9.B) The time between applying pressure again (letting the weight fall) and letting go.9.C) The speed of the motor.- The above 3 should have some 3 knobs to adjust timing and speed. 10) A DC-based wiper motor uses some 1-2 Ampère when there is no resistance. Thereby it ought being able to run for days without charging.11) I would - at appropriate places - apply even a Solar Cell with some 8 times the wiper motor charging capacity (to provide power the 4 out of 5 hours where there is no sunshine) + charging unit - such that it can even be setup anywhere as long as there is daylight.12) I would use much larger tubes.13) The valves I would use such that the air container with the weight on, fetches fresh air from outside, and when the weight is applied, it blows into the patient's lungs.14) I would ensure that the air container is extraordinarily solid and durable, as it will have to operate some 10,000 breathing operations per day.15) I would make the wiper motor slow-start, with a Capacitor - thereby ensure durability and pleasance for patient.16) I would 3D-print the piece which would fit with a mouth piece. 17) I would 3D-print the mouth piece too.18) The 3 regulators of let-go time, breathe-in time and speed of motor, should be available for the patient.19) The mouth piece should be fit with standard gauge pipes.20) We should indeed get the dimensionality of this.

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  • How to Build a Full-sized All-Terrain Tracked Vehicle From Junk (the Ultimate Bug-out Vehicle)

    Your belts will not last long. You need hinges all the way round. Metal.fatigue will set in and they will break off. So. Get on with making hinged tracks. You need slightly stronger metal for.your track. I would say some pieces of 3/8 inch thick flatbar would do the trick.

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  • Beautiful!!!! Thanks for sharing. I will build such a clamp with bender...

    Not a necessary comment. Who cares if he is a DIY and makes it work and you are a DIY and you cannot make it work. Negativity is not working anywhere in this world.

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  • Hu, you mention Zinc Sulphate in previous point and suddenly introduces water and zink salt? Where did the electrolyte dissappear to, and where did the salt suddenly come from? I am a newcomer so maybe I am just a bit to new to understand if the salt is the same as the electrolyte.If it is the same, then I would like to know how much H2SO4 and how much zink is needed to create 100 gram equal of salt? My guess would be to calculate using molar mass, from secondary school chemistry, .. ??? how concentrated should the H2SO4 be? Like battery acid? Thanks for such a well written article!!!SincerelyDavid

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