I Will Pull(ey) Through!


Okay so I’ve got good news and bad news. The good news is that I’ve found Pathfinder. The bad news is that I can’t get to it. At least not yet.

See the thing is that it’s stuck in a crater that’s way too steep to drive down into with the rover. What must have happened was that the balloons that are supposed to protect it during landing malfunctioned and never fully deflated which re-inflated and basically made this chunk of metal into a rolling beach ball. The Martian dust storm that forced us to abort our mission probably brought a gust of wind necessary to send this contraption rolling.

Luckily, it still looks intact. I guess the balloons did their job. Although, what I was a bit worried about was Sojourner. Sojourner is the mobile part of Pathfinder. While Pathfinder was just built to remain stationary, Sojourner was made to be able to move around and collect rock samples of the environment.

I assumed that since it was smaller than the lander, the wind could have probably carried it farther. I looked down into the crater hoping to find the little nomad but saw no sign of it. All I could see was red dust and boulders. Great. But that’s when I realized that it was probably just hidden in a pile of rocks.

I guess it must have wandered too far and got itself jammed in a mass of boulders.  Looking around, I found the nearest pile of rocks and began digging. Sure enough after removing only 2 basket-ball sized rocks, I finally found good old Sojourner lodged between two larger stones. Once I got the little guy out of there, I was so relieved that I now had a new supply of spare parts. It almost feels wrong taking Little Soj apart right after rescuing it.

Okay. Talking to myself is one thing but personifying inanimate objects could actually make me go crazy. Oh crap, I’m becoming like Chuck Noland from Castaway.

Nah, never. I’ll just ignore the fact that we are both isolated in a remote environment and that everyone we know thinks we’re dead.

I really need to get Pathfinder working again! In this case, communication is not only crucial to my physical health but also my mental health. I sure as hell am not going to draw a face on a potato and call it Wilson.

Anyways, I still have the massive dilemma about the best method to retrieve my beach ball of a radio. Going down there with the rover is far too risky while trying to haul it up the wall of the crater by myself manually is just nearly impossible. To carry it, I would have to deflate the balloons otherwise I could never get a grip of it. It would be stupid to try to carry it and end up letting it slip from my grip and watch my chances of returning home topple back down into a hole of despair.

Yeah definitely not going to do that. Well, it looks like I’m running out of daylight so I have to go pack up my solar panels. I guess I’ll call it a day. Another night in the rover.


Okay I’ve got it!

So I don’t have a crane, tow-truck or anything else that would make this situation simple. (Come on NASA, what were you thinking sending us up here without such crucial tools?) But what I do have is a ton of Hab canvas and a tough rover. So I’ll just tear the canvas, knot the pieces into the strongest rope made on the planet. And I can totally say that because everything I do here is making and breaking records. Good thing I’m recording this log. The next colony of Mars has a right to know about their history. (You’re welcome future Martians.)

Anyways, once I have my fancy rope, I’ll tie one end to the rover, and go down into the crater holding the other end (well roll down into the crater because it’s actually that steep of an incline) and knot it around the machine so that it can’t slip out of the rope. This is where my 5 years of boy scouts will come in handy. I don’t have a ton of Hab material but a couple meters is all I need because the crater isn’t that deep, it just has an almost vertical inner wall. I figured that since the crater is 4 meters deep, I’ll need at least 10 meters of rope, which I definitely have.

Then, I’ll use the rope as a harness and pull on it to scale the edge of the crater just like a mountain climber. Woo! I’ll get to put on my “Extreme Alpinist” hat (just pretend the depth of the crater is 400 meters instead of 4 meters). Once I get to the top, I’ll have to make a boom and lever that would be strong enough to hold the weight of this thing.

I figured I could just take the wheels off of Sojourner and use 5 of them as pulleys and keep one as a reel giving me grip to pull the rope. The pulleys will multiply the lifting force my muscles supply. The more wheels I use, the more sections I can separate the rope into which means the more I am able to divide the weight of the lander.

If I use 4 pulleys, and allow the rope to be divided into 4 different sections, that’ll reduce my necessary input force to a quarter of what it would have been without the pulleys. Therefore, my mechanical advantage is 4.

I really love physics in times like these. The only downside is that I’ll have to pull the rope a longer distance to do the necessary work but that shouldn’t be a problem since I have more rope than I need.

However, my next question is how to make the boom. Time to put my mechanical engineer hat back on. There is an L-shaped bumper that runs around the sides of the rover that are in the blind spots of the driver. It runs around the back and the right side of the vehicle. This bumper was supposed to give the rover a little bit of crush space if it were to hit a boulder but I think I can just take my chances driving without it. I’ll use it to make the beam and boom. I’ll actually have to take it entirely off the rover and then put it back on but reversed.

This metal bar of a bumper is secured by 2 bolts on the ends of each of the sides of the rover. So, I’ll have to undo the bolts, take it off, invert the beam so that the long part of the ‘L’ is along the wall of the rover and bolt it up. It’s a good thing that this bumper has pre-drilled holes each already spaced 5cm apart. Once I do that, I’ll have to fix my pulleys to the short side of the ‘L’ and run my braided Hab rope through it. So, I’m gonna give it a shot! Here goes something…


So, the good news is that it worked! Once I ran the rope through the pulleys, lifting the lander out of the crater was a piece of cake. Since I used 5 pulleys, the force I had to apply was 1/5 of what it would have been to lift the thing. Lifting A 200kg lander felt like lifting a 40kg probe! Well done physics.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s