19 Jul Colorado School of Mines, Week 6

It is now the end of week 6 here at the Colorado School of Mines where I am working on building the IPEx rover in the RoSE lab and we have working avionics testing has begun.

Working on the power supply to connect the motor prototype

Let’s start with Monday I was working on updating the data sheet I’ve been making and updating the wire diagrams with the new stepper drivers and the new strain gauge amplifier components. This is where I wanted to research specifically how the amplifier works so that I know which wires connect where and I found that I will need two other components to make it work. The first one I need is called an ADC or an Analogue to Digital Converter because the strain gauge amplifier outputs a voltage from how much strain there is and a raspberry pi can’t read voltage just if there is or isn’t voltage so we need the ADC to covert a specific voltage to a binary code of pulses of power that can be read by the raspberry pi. The other component I was going to need is a buck converter which steps down the voltage of the battery from 24V to 12V so that it doesn’t fry the amplifier. This was about all that happened on Monday but Tuesday was a very exiting day. I started the morning finishing the work from Monday but I was then asked to help connect the motor and the components needed to get it to spin and a little bit later we had our first motor spinning and the whole thing working with the custom made wires and a software in a computer.

Motor setup connected to a computer

On Wednesday we were able to get the motor spinning off of the teensy and began to work on getting the teensy to talk to the raspberry pi. Along with the motor there was a proposal during the meeting to use electromagnetic brakes to hold the arms up was driving around. I did the math to see how much this would benefit our rover and it ended up doubling our battery life and runtime on the second battery. This was perfect and would also connect the same way to the motor controllers and brains of the rover, the only difference that needed to be solved was that the brake needed power and it couldn’t get power from the stepper drivers. This was a pretty simple problem and we could just use a relay to send power to the brakes with a signal from the teensy. This brings me to Thursday and Friday where I continued to work on the data sheets and diagrams to update them with the new components along with helping to make wires and connectors to continue working on the software for the raspberry pi to talk to the teensy. I also began to work on my CDR presentation (Critical Design Review) which is similar to the PDR that I did a few weeks ago but this time more in depth with new research and this is where we prove that this project if fully possible and will be able to be built.

Under one of the three bomb bays in the B-1A Lancer

Climbing in the wheel well of the   A-7 Corsair II

Outside of the lab this week I continue to go on bakeries and have been enjoying exploring to the east side of golden and the paths and trails that take me that way. I also continued to work on my flight training this week I learned how to use a glass cockpit where all of the different instruments are shoved into one big screen where I can find everything. I also went to go see the Wings over the Rockies Air and Space Museum on Saturday where I spent the whole day learning and exploring each part of the many aircraft they have and how they work. I am exited to get a further developed prototype of the avionics working and start to connect subsystems together.

Morning preflight in the G1000 172