Hi guys am a complete novice in this world but i wanna try and build a project of Dslr buggy which can handle a load capacity of about 6kg, i dont want speed but something that can travel atleast 800m without loosing connection, this would be mainly used to photograph and video wildlife that are skittish of human presence, any help in this matter would be great i have looked at Recon Chassis Kit but have no idea how to go about it, if someone has built something similar that would be awesome or if someone can point me in a right direction that would be even awesome, Thanks a lot in advance !
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Hi Mickey.
I’m interested in something similar – spy on shorebirds – but not from a mobile platform. Looks like a LoRa setup is the most suitable comms method for something like your application where you need to send various commands a long way.
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Hi John
I already have something to trigger the camera i just need to put together a rig to carry the setup to the wildlife, have you made your setup yet if so i would be interested to know more, thanks for your reply
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Hi @Mickey272649, Welcome to the Forums!!!
This sounds like a really cool project. I hope you keep us updated as you work your way through it.
If you’re just looking for a platform to move the camera remotely without any autonomous capabilities the best way forward may be looking into RC cars/tanks as the base platform.
For control a simple RC controller such as this one would work well for controlling motors or servos on the platform.
If you’re looking to be able to see a live transmission of the camera feed from the platform that does make it a bit more complicated but still very do-able. Some good search terms for finding information on systems for live video transmission would be FPV or First Person View systems or if you need higher quality wireless video transmission system from companies such as Hollyland, DJI or Teradek would work well.
I hope this helps you with some starting points for designing a system that works for you.
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Hi All
Some of the David Attenborough footage shows some clever disguises for wildlife photography. Such as a rock or similar. He had to be careful sometimes and I think they lost some gear when Elephants trod on it.
I think it was mostly fixed though and I don’t think much of it was mobile.
Cheers Bob
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Hi Aaron
I have been on this for a little while, i did buy one RC for about 300 but it just couldn’t handle the terrain or weight so am here. I did have a look at the dji transmission combo but thats a little out of my budget but i have one which works well if its within 400m
i was looking at gobilda recon chassis kit but not sure how hard its gonna be to build it and if it will be right to go on uneven terrian behind wildlife.
Thanks for your reply
I have seen a few videos where they used it for tigers in India too but they are with unlimited budget for them to loose a few makes no difference.
Hi Mickey
Yes they don’t seem to be too short of a dollar or two.
Cheers Bob
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Hey Mickey,
You seem to be on the right path with that one. The Recon Chassis is a pretty great piece of kit and its instructions are pretty great. Used in combination with their radio control module you can theoretically get up to 800 metres line of sight control and you would have 2 additional control pins on the receiver to attach any camera equipment controls you may need (with a bit more tinkering).
Form our project using a similar Gobilda Chassis I remember there being very minimal noise from the motors used in the kit, so it would be pretty good for the use case you are looking at.
Cheers,
Blayden
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Thanks Blayden
so apart from the kit and radio controller all i woould need would be batteries for it, my biggest questions are would this be able to haul a 6kg camera setup and weight of batteries that it would need for power, also would it be able to handle all terrian as in long grass or uneven dirt road
Thanks for your help !
Hey Mickey,
The batteries are generally going to be NiMH batteries like this one. With that particular kit you should have more than enough force from those motors to move a rough total of 10Kg.
Regarding terrain, it should be fine to use for most places, though be aware of something getting caught up in the wheels if you are driving through long grass.
Cheers,
Blayden
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Thanks Blayden
how long would one of those batteries last i know it will all depend on the terrain and load but can it give like 30min run time ?
Runtime can be a tricky thing to calculate unless you know a lot of variables.
The battery @Blayden linked is rated for 3Ah.
Running a constant 6A load at 12v would give you an approximate 30-minute runtime.
Looking at the motors used and their Stall current and no-load current you can calculate the runtime will be somewhere between 5 minutes and 3 hours
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Thanks Aaron
to be honest i have no idea what stall current mean, i think am way over my head with this project, looks like a lot of studying to do in this field
Stall Current is fairly simple, If a motor has a load big enough to stop it from spinning the max current that will pass through it is the stall current.
I’ve spent a bit of time building quadcopters and runtime can be a tricky thing to figure out.
Unless you know exactly how much power a device will use over a given time it can be hard to guess how long a battery will last.
The best thing I was able to do was monitor the battery, either by Voltage or Power used with a current sensor and stop flying when the battery was getting close to depleted.
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Hi Mickey
Aaron has described the stall current OK. It is usually the maximum current the motor will ever use and it is a good basis to start working out your maximum demand.
You don’t have to measure the current if your motors are the brushed type. Measure the resistance of the winding across the terminals and calculate it. Applied voltage (Volts) divided by resistance (Ohms) will equal current (Amps). Try several positions of the motor as the resistance between brushes and commutator will vary a bit. Pick the lowest reading.
Warning. Don’t rotate the motor with a meter connected to measure resistance. The motor will become a generator when rotated and could possibly damage the meter.
If the motor is fitted with a gear box you might have trouble rotating it. In this case you will have to move it a bit with the power supply. Make a few measurements and pick the lowest.
Cheers Bob
EDIT: Applied voltage above is the voltage you intend to use to drive the motors in your situation.
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Thanks Aaron
will weather as in temperature in summer affect the run time as well ?
Thanks Robert
i am trying to understand what you said but this is definitely not my field and might take me years to really comprehend what you said here but am gonna try and learn as much as i can.
thanks for your help !
Hi Mickey
It is fairly easy actually. When the motor is at a standstill (stalled) the supply will see the DC resistance of the winding. That is what you are measuring with a meter in my explanation above. The current can then be calculated using Ohms law which is E (Volts = I (amps) * R (resistance).
I might add an important item here. Because the motor is at a standstill at start up this will also be the inrush current at start up. So this is the current that will be drawn at start up and has to be catered for in the supply capability. Only for a short time but the requirement is there. The run current will be far less but the motor has to start moving.
Cheers Bob
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Aaron
No it wouldn’t. That 3Ahr would be at the 20 hr rate or if the battery was discharged over a 20hr period or to put it another way C/20.
You are quoting a discharge current of 2C or twice the rated 20hr capacity.
I think you might find that any battery no matter what the chemistry will derate at this discharge current.
So in a nutshell at a discharge rate of 2C the battery will not last for your quoted 30min(approx). It could be quite a bit less.
Cheers Bob
Add on to above
A bit of research and I dug this up.
This graph is targeted at AA construction but it would probably apply to any cylindrical device. The battery in Blayden’s link could be “C” or “Sub C” but this should give you an idea of what I was talking about above regarding derating the battery capacity.
This graph indicates that a discharge rate of 2C the capacity should be derated to about 75%. In this case of a 3Ahr battery the capacity should be reduced to 2.25Ahr which is a fairly substantial drop from Aarons quote earlier.
In fact the full 100% capacity is not realised until the discharge rate is reduced to C/5 (0.2C).
This information obtained from this web site and is worth a read.
Cheers Bob
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