Progress Update

There hasn’t been an update on my site for a while but the projects haven’t been abandoned. All of the projects I’ve been a part of, have been delayed significantly due to my ongoing struggle with depression and coping with it, but I won’t go into that in this post. So you may be asking on “what has he been working on?” at this point, and the primary thing I’ve been working on is changing my circumstances for the better to make my depression more manageable, although this doesn’t mean the projects haven’t had any progress.

Project MEHA (Micro Electric Helicopter with Autopilot)

When assembling the base helicopter that the project revolves around (ELE Firefox EP200); I accidently stripped the thread of the main shaft collar which means I need to get a replacement, another part that required replacement is one of the tail boom arms as the end cap which allows the arm to be screwed to the body, snapped off when assembling, however has had a temporary repair with CA glue and a bit of tissue. The has also been a problem getting the motor mounted, as there were no mounting screws included with the motor which means I’ve had to try to find out the screws required for the motor to allow it to be mounted. The pinion has been fitted to the motor with the assistance of a vice I made in my first year of my engineering course.

Project SEPA (Small Electric Plane with Autopilot)

The plane has been a little bit of a worry, the foam quality is good (although the yellow ‘paint’ has been flaking off in several places) but the space inside the plane is a lot smaller than I expected. I also have a small problem with the RC receiver I got for both SEPA and MEHA currently doesn’t fit inside the plane, holding the cockpit open; however I can fix that by modifying the RC receiver with a right angled header so it will be more ‘flat’, so I need to buy another receiver as I don’t want to have something go wrong (like a PCB pad falling off) and then being without any receivers for either MEHA or SEPA which will further delay the project. Mounting the new servos is going to be an issue as they have been glued into the place.
The other thing I’m doing is reinforcing the leading edges of the wings, rudder and strengthening the control surfaces with fibreglass as there is a lot of flex in the control surfaces, another thing I’ll be doing is switching from a thin bit of foam holding the control surfaces on (which I’m worried will fall off) to hinges to allow easier movement of the control surfaces and reducing the chance of the control surfaces falling off due to foam fatigue. The last modification to the plane is I’m going to be removing some of the foam inside the plane and reinforcing those sections with fibreglass to allow more electronics to fit inside the aircraft.
Another thing that has been a problem is finding a place where I can legally fly the aircraft and this will be a future problem as I can’t fly the aircraft with the cockpit open. I may need to sign up for a club before I can fly.

Photos for both MEHA and SEPA will be coming soon.

University Project – Twin Bladed VTOL

This project is ending soon and hasn’t progressed as we would have liked. Currently I’m working on getting a rig set up which allows the power of the engine (in terms of thrust) to be tested, looking at the relation of current required for a given thrust output when we give the speed controllers a certain value. It involves a couple of strain gauges (allowing the measurement of flex in the load bar) and amplifying the tiny changes in resistance of the gauges to allow them to be read by a microcontroller.
I should also mention an unsuccessful attempt to get the aircraft to hover which highlighted problems with the procedures used to handle the aircraft. Hopefully these will be rectified before the next test.

New Projects

I’ve actually been planning several projects for some time which don’t require any more resources than what I already have. I’ll be giving more detail in the future but here is a rough summary of each of the projects I’m planning on doing:

  • RC Car Automation – I have a couple of RC cars which were sitting around my room and have decided it’s actually the perfect base for me to start trying out automation, which can fold into the navigation core of the MEHA and SEPA projects, and getting familiar with GPS systems. This requires integrating a Bluetooth GPS module I have with my microcontroller and getting the microcontroller to parse the NMEA strings
  • TI EVALBOT libmaple port – I bought a TI EVALBOT kit when they were available for $25 (a code accidently got leaked, possibly the reason why was born), and haven’t touched it since assembling the robot. I had already thought about porting the libmaple code base to the EVALBOT but didn’t know if I could manage the task myself. However, as I’ve been learning more about ARM microcontrollers (slowly I might add), I’m now at a stage where I might be able to tackle this challenge. This is going to eventually require a JTAG debugger/programmer (I believe), but will provide better knowledge of ARM microcontrollers than I have currently. Also it will help develop my coding skills better which are feeling quite lacking as this semester is coming to a close.
  • Bus Pirate v3.5 SOIC Free PCB Build – About a month ago I acquired a free PCB (after trying for weeks to get one through comment posts and twitter reposts) simply by asking for a coupon and got a Bus Pirate v3.5 SOIC PCB which I’m planning to populate. I’m currently trying to get all of the tools/parts required to assemble the PCB and need to get the last few parts before I assemble everything and attempt to program it.
  • STM32F4DISCOVERY – I’m currently getting a STM32F4DISCOVERY board and will be trailing the microcontroller as it could be the base of all of my future projects which require a powerful microcontroller (UAV projects). The main point of this project is to learn more about the STM32F4 and Cortex M4, seeing how hard it is to develop for it and assisting in porting libmaple to it. I don’t believe I’ll need anything apart from the STM32F4DISCOVERY for this project. This project will also assist with the TI EVALBOT libmaple port.
  • New Equipment

    After wanting an oscilloscope for over 2 years after using them at my university to analyse digital circuits, I finally got one of my own! I also have a tip about deal extreme, don’t pay the extra for EMS shipping. It took 8 business days to get my parcel, and deal extreme has refused to refund the EMS shipping as they don’t care about the fact the parcel was beyond the ‘maximum’ delivery time, even though they sold me the service. Anyway, getting back to the oscilloscope, I got a 50MHz bandwidth Rigol DS1052E Digital Storage Oscilloscope, and for the price, it has been awesome, it’s currently back in its box as I need a more permanent place for it than just a lap desk on my bed.
    I also plan to get a toaster oven in the future for reflow soldering purposes, but that's when I can afford the other equipment needed for it (thermo-couples and thermo-coupling amplifiers). When that happens, I'll probably be attempting my first SMD PCB design.