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Software / Re: Anyone tried Windows 7 for robots?
« Last post by elwishtwo on November 25, 2020, 11:21:28 AM »
I have downloaded the community edition but unable to install it. Itís asking for the .net framework. I tried installing the .net framework 4.5 / 4.6. None of them are getting installed on my system which is windows 7 . Have Installed SP1 as well. Could you please support me about what is to be done next.
Electronics / Re: charging two diffrent types batteries with one charger
« Last post by bdk6 on November 24, 2020, 06:16:00 AM »
Every type of battery has different charging requirements.  Lead Acid and LiPo are VERY different.  Each should have a charger especially designed for it.
You don't state what type of "charger" you are using.  I have a feeling it isn't intended for either type of battery.
LiPo batteries are subject to catch fire or even explode if charged improperly.  Lead acid is less dangerous but can still be damaged or destroyed.
I HIGHLY recommend you buy appropriate chargers designed for each type and use ONLY those.

There is a great deal of information on batteries and charging here:
Electronics / Re: PCB assembly company recommendation?
« Last post by bdk6 on November 24, 2020, 06:08:48 AM »
At work we have started using
I have been very happy with the quality and service.
Software / Re: Skid Steering (Differential Thrust) on a boat calculations
« Last post by bdk6 on November 24, 2020, 05:54:39 AM »
I'm not sure exactly what you are asking for, but maybe this will help.  If I'm not on track, let me know.  I may be able to clarify some things.
To restate the problem, you want the boat to move forward and possibly turn left or right some amount, based on an input variable from -1 (left) to 0 (straight) to +1 (right).

There are many ways to approach it.  This is one.
To move straight ahead both motors should turn the same speed.  Let's start with 50%
To turn left, the RIGHT motor should turn faster than the left.  Since there will be more resistance, let's keep the left motor the same speed and turn the right one faster to minimize speed change.
To turn right, the LEFT motor should go faster, similar to above.
Let's write some pseudocode to set two variables to the desired PWM percentage.

leftMotorSpeed = 50;       // First set both to 50%
rightMotorSpeed = 50;
differentialSpeed = turnVariable * 50;     // differential speed will be somewhere between -50 (for -1) and +50 (for +1)
// Now add the differential to the appropriate motor
if turnVariable < 0
   rightMotorSpeed = rightMotorSpeed + abs(differentialSpeed)  // add the absolute value since the differential is negative
if turnVariable > 0
   leftMotorSpeed = leftMotorSpeed + abs(differentialSpeed)     // doesn't really need the abs() but I like to program defensively
// if it is not greater than 0 or less than 0 then it is 0 and doesn't need to be added

Now you can convert those motor speed percentages to whatever values you need and send them to the motors.

Does this help?
For Sale / Professional and deepened robot chassis and duct cleaning robot
« Last post by Defy on November 22, 2020, 07:28:36 PM »
We specialize in the research and production of robot chassis and duct cleaning robots. If you are interested in them, you can visit our website for more details.
Electronics / Re: PCB assembly company recommendation?
« Last post by Loveironsight369 on November 14, 2020, 02:11:56 PM »
I havent tried this one yet. but it seems good.
Robot Videos / Re: RoboOne biped battles flying robot
« Last post by Loveironsight369 on November 14, 2020, 01:51:20 PM »
 ;D ;D ;D ;D ;D ;D ;D I Guess great minds think alike and i'm new trying to see if theres room for to can of thing to go main stream. but biger and more stuff.This is the first thing i research on this forum was 'Battle' lol
im an inventor that trying to make my on design
Software / Skid Steering (Differential Thrust) on a boat calculations
« Last post by grimsy on October 29, 2020, 05:52:56 PM »
The usual starter line, if Im not in the right place let me know but heres the story:

Ive got a model boat wired up with a raspberry pi(Experimenting with python I'm aware there's better options haha), wired up to two regular DC motors. Now I feel like I'm missing something simple here, probably just blind from staring at the thing too  much, but I cant figure out how to calculate the differential steering at all. I'm completely clueless. admittedly calculations arent my strong suit, this is just a hobby for me.

So basically, I have an initial thrust value of 0-100 and a steering value of -1 to 1. -1 on steering being left. Reversing will come later, first I gotta move at all  :D

So what I've got to figure out is what the right motor PWM and left PWM is for any given value of the two variables.

As I said, its a hobby, I may be doing something stupid or ridiculous here so let me know, I'm beginning to doubt if python really is the best choice and I'm thinking of migrating over to c++. Either way though if anyone can give some advice or even just point me in the right direction to figure out the problem it would be very much appreciated.
Mechanics and Construction / Soldering a lead to a motor that connects to a receiver.
« Last post by nastycpa on October 28, 2020, 12:43:39 PM »
I have a motor, I have lead wires and I have a receiver. 
I can solder the lead wires to the motor and plug the other end into the receiver.  The problem is that I can't figure out what combination of wires (Black, Red, Yellow) to solder onto the motor.  I currently have the Red on the positive and black on the other However that results in the motor running nonstop (even when the controller to the receiver is turned off).  All other combinations result in no movement. 
Picture attached.  I probably need to solder the yellow wire to the motor some place...
Any advice?
For Sale / Velodyne VLP-16 For Sale. New opened box.
« Last post by cowboyzack on October 25, 2020, 06:45:58 PM »

Iím selling A Velodyne VLP-16 lidar. Its unused and its only been opened for display purposes.

It comes with the interface box, ethernet cord and DC power supply

Ready to ship anytime

Here is the EBAY listing :

Price: $4000 obo
Please dm me if you have any questions

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