A short video demonstrating a quick and easy way to build a charge protection board for 3s (3 x 18650 batteries in series). 3 x 18650 in series will give you around 12v. The board will help protect the battery pack from overcharging, over-discharging, over-current and short circuit.
We’ve finished building the prototype of the LinoRobot and have an understanding of how all the software and hardware fit together.
There was a few issues along the way and ill summarize what we’ve learnt:
- ROS and the navigation software requires a faster machine than the current VM. Now we understand more we’re going to build ROS on the direct hardware.
- The Raspberry PI doesnt have SWAP memory enabled by default and ROS ran out of memory when first starting ROS. Enable SWAP for initial ROS startup and then disabled it.
- We cheated the first time by using ubiquityrobotics ROS image the first time and we’ll probably cheat again, it makes setup a lot easier 🙂
- Don’t use very cheap cheap motors as they don’t give similar results and the robot goes around in circles. We bought some more expensive motors this time so hopefully they will move when we want them too.
The parts have arrived and we’re now getting started on the second robot.
Sheffield Hackspace has setup and installed a LoraWAN (The Things Network) gateway. LoraWAN is a new technology that enables small amounts of data to travel large distances with low power and the best bit of it is….its free!! This is being used by universities, corporations and hobbyist a like to transmit data such as air quality, traffic, temperature, gps informational ect. from battery (or wire) powered devices that last up to 10 years and more.
Come to the Sheffield Hackspace to learn about this new technology and make use of the gateway to prototype your idea. If you want to make your own gateway and add to the things networks, come and learn how to do that. See if your area has a gateway installed by clicking the link here.
For our gateway, we used a Raspberry Pi and RAK 831 to receive multiple frequencies at the same time. For some unknown reason the RAK 831 use to switch off occasionally so we’ve added a on/off relay (as can be seen in the photo) to power recycle it automatically/remotely when when it stops responding to the Raspberry PI. Hopefully we’ll find the root cause.