A bike riding robot
Tue, November 15, 2011 The above video is a demonstration of a cycling robot built by Japanese engineer Masahiko Yamaguchi. The tiny mechanical cyclist keeps its balance in the same way a human does by steering in the direction the bike and rider is leaning or falling.
The robot has a sensor in its back pack that detects a lean to the left or right, and this in turn causes the robot’s arms to steer the bike in the required direction.
A human will do this intuitively, as we fall to the left; we steer to the left bringing the bike back under the center of mass, or balancing point. Rather like balancing a broom on the palm of our hand, we do this by constantly moving the palm of the hand in the direction the broom is falling.
Conversely, if we want to turn to the left we lean to the left. We automatically steer to the left to correct the lean and therefore make a left turn. Even when running we lean in the direction we wish to turn, all animals do it.
By leaning we automatically step in that direction and in doing so make a turn the way we are leaning.
For both the runner and the cyclist, the lean also counteracts the centrifugal force, pushing us outwards, that the turn generates.
You never rarely hear of a bicycle or motorcycle tipping over on a corner as a three or four wheel vehicle might do; or for that matter a runner falling outward on a bend. Rather the bike, or the runner’s feet may slide out from under them.
There are two ways to balance on a bicycle. The easiest way by physically steering the bike in the direction we are falling. (The way the robot does it.) Or we can even ride “No hands” and both balance and steer by shifting our body weight.
This requires more skill but as most of the body’s mass is in the upper body; the rider mostly has only has to move their hips to achieve balance. This too is somewhat of an intuitive movement.
Have you ever been riding near the edge of the road and find that the asphalt drops off several inches? Your bike is leaning towards the edge and normally you would steer in that direction to correct it; only you can’t because you will steer yourself off the road.
Instinctively, you throw your opposite knee out away from the edge; move your hips towards the edge and your shoulders away from the edge. You have maintained your balance by moving your body weight rather than by steering. It was an intuitive movement probably accompanied by a moment of sheer panic.
This is why the bicycle is such a remarkable yet simple invention. It is relatively easy to balance and ride; after all a child can do it with a little practice.
It is a similar to the intuitive thing that we do while walking or running; the bicycle could be described as a mechanical extension of the human body.
Footnote: There is more to steering and steering geometry than this simplified explanation. There are several articles in the bike tech section of the archives.
Portland BTA’s shift on helmet use
Portland, Oregon’s Bicycle Transport Alliance (BTA) is no longer opposing helmet laws. They are not necessarily supporting them, or pressing the state to implement mandatory helmet use, but if the state decides to go that route, they will apparently not oppose.
They had this change of policy after polls have shown that 80% of their membership already wears protective headgear.
Mandatory helmet use is not the way to reduce cyclist injures and death. The only ways to reduce those is by education of both cyclists and car drivers alike, and prevent the crashes in the first place.
Mandatory bicycle helmet use is a “Blame the victim” fix. Many pedestrians and even car drivers also die of head injuries, but no one suggests helmet laws for them.
I have heard the argument that a cycling advocacy group opposing mandatory helmets is like an automobile association opposing seat belt use. Not the same thing, seat belts can be proved to save lives, bicycle helmets cannot.
If a cyclist is run over by a vehicle and crushed, whether or not he/she is wearing a helmet is immaterial. If a cyclist is hit by a car doing 50mph or more, internal injuries and broken bones from the impact alone are going to be serious or fatal, and wearing a helmet will make little or no difference to the outcome.
I wear a helmet when I ride my bike, not because I believe it will save me from serious head injury, but because I believe the little protection it does give can’t hurt.
Another big incentive for me is, in the event I am hit by a car and injured; when I make a claim with the car driver’s auto insurance, they cannot say I was negligent and contributed to the seriousness of my injures by not wearing a helmet.
Insurance companies are notorious for finding ways to pay less or not pay at all on a claim; why give them the opportunity to deny a claim by not wearing a helmet? Apart from that I believe this little piece of lightweight Styrofoam I wear on my head offers only a token amount of protection.
These are my personal views; I would not tell anyone they should or should not wear a helmet when riding a bike. I strongly believe that helmet use should be an individual choice.
Whenever mandatory helmet laws have been introduced, like in Australia and New Zealand for example, the result has been a large drop in bicycle use.
Ask yourself this: Would you wear a helmet to walk around your city, or when your drive a car? I certainly wouldn’t. Why? Because it is unnecessary, and I would look stupid; some people who ride bikes feel the exact same way.
Driving a car or walking is not necessarily a choice; we all have to get to where we need to be by some means or other. But riding a bike, for many cyclists, is a conscious choice and therefore wearing a helmet should also be left as a conscious choice.
Portland’s BTA calls its shift in policy is a "Slight Modification," but by standing on the sidelines and saying “We no longer oppose mandatory helmet laws,” is not doing any favors for its membership or the cause of cycling. Just because most of its membership wears a helmet anyway is not a reason to no longer oppose.
If you cause cyclists who are just starting out, to quit, and discourage new cyclists from riding a bike, it will jeopardize a whole city or even a state’s cycling initiative.
This is a bad thing for all cyclists, we need more people to ride bikes not less. Get people to ride bikes first, educate them to wear a helmet later if you feel it is necessary.
In a way the helmet becomes the badge of a serious and committed cyclist; most will start wearing one when they reach that level without prompting from others.
The fact that the majority of Portland BTA members already wear one shows this. Only people who are committed to cycling are going to make the effort to join an association like the BTA.
Cycling is all about freedom; and I would hope that any cycling advocacy organization would continue to strongly oppose all attempts by legislators to take away the individual freedom of choice to wear, or not wear a helmet.
Footnote: Relavant to this post is a story (With video.) from Austalia, of a film-maker's bid to repeal mandatory helmet laws.