Steady Beats to Transfer Tendons

INSTRUMENTS (#10)
by Tim Phillips

Progress is being made on the new Drum Machine! I'm still searching for a better name, if anyone has ideas.

Although my initial mock-up proved the concept, it grew disappointingly limiting very quickly.  
This was it if you missed it:  
Here are some of the issues I have been trying to solve:

1. As exciting as cranking a handle is, I quickly realized that I needed the gears spinning at a steady rate to allow any real exploration of rhythms
2. Another issue is that every other gear alternates which direction it spins, but the ramp only works in one direction.  I need something that goes both ways but still has the sudden drop so that the stick strikes the drum.
3. Most importantly, it needs to be easy for anyone to change and play with the rhythm.

Firstly, I set to work cutting out plywood gears.  While it is really satisfying to learn that you can cut out a wooden gear by hand (thanks to Matthias Wandel!), after doing 6 I’ve already started looking for access to a CNC machine!

I managed to get the gears running on a motor from a disco ball and began testing an alternative to the ramp.  This was a real maker geek moment for me, (I’m sure there is a specific term for that) the iterative process and the proud smugness I felt following the solution!

It went like this: Ramp; different shaped ramp; double-sided ramp; pipe; ball; ball on string; pipe on webbing; binder clip on webbing; success.


Here is the end result:
The webbing allows the clip to fall either way, and the clip acts as a sprung ramp in either direction.

The best bit though is that everyone knows what to do with a clip - Squeeze it... take it off, put it on... making it easy for anyone to mess with the rhythm.

Notice that you can also control the volume of the beat (i.e. adding accents) by using bigger or smaller clips...


Next up is sourcing the parts to make the real thing!


CHARCOT MARIE TOOTH
post by Tim Phillips


You are all part of the CMT circle now, so I thought I’d introduce a topic which is always hotly debated among CMTers, it is that of surgery.  It is debated because of its mixed success rates and very likely a wide range of expectations.  Almost a year ago, I had extensive surgery on my foot.  I am comfortable now saying that it was a success and wanted to give some insight into the experience.


Hopefully you remember that CMT affects the peripheral nerves, over time this causes the extremities to deform in different ways.  My issue that the surgery hoped to address, was with my right foot.  Ok, so remember that nerves in the body not only control the senses, but the motion of all our muscles too.  As I grew older and my peripheral nerves degraded, I not only lost the feeling in my feet, but also the mobility.  One by one the tendons (which attach to the muscles) gradually shut down.


However, for some unknown reason, in the foot there are two tendons that remain unaffected by CMT.  One pulls the foot down, and one pulls the foot inwards.  Although it is great that something is working down there, this causes a problem which is unaffectionately called ‘Club Foot’.  The reason being that the foot is unbalanced, constantly diving down and in, resulting in chronic pain in the joints.


The surgery I had is simple in theory, yet marvelous (and extremely painful) in reality.  The idea is to balance the foot.  The surgeon detaches the tendon that is pulling the foot inwards and reattaches it to the top of the foot to pull the foot upwards.  Therefore you’re left with one tendon pulling down and one up; a balance; no more constant pressure; no more constant pain.  

A couple of 'how-to' diagrams...

As I said, this worked as planned for me and I’m very glad to have done it. I’m now without that joint pain and a lot more stable.  Although successful, it must be said that I wouldn’t wish the surgery and recovery on my worst enemy!  My foot was completely immobilized for about 7 weeks and I was tortured by highly trained people throughout.  

During that time I started to note what I was thinking about my foot, I’ll leave you with a few of these thoughts...

• There is something fascinating about moving really slowly
• It’s not my foot
• Progression to the next stage comes with delight, fear and sadness
• Twin Peaks on Norco is something else!
• So much time 
• Note to self, don’t let drunk friends write on cast just before spending a week in a children’s museum
• Ooh, it’s so scaly
• I guess I didn’t really realize the extent of what they were going to do to me, perhaps that’s a good thing
• This might take a while; I should learn how to live life like this rather than waiting until I’m better
• Ha ha! I can walk  [veeeeeery slowly].

(For the docs and other surgery goers, this is what I had done: Transfer of posterior tibialis tendon through interosseous membrane to dorsum of foot; transfer of peroneus longus to brevis; Steindler stripping)