CN104984531A - Bicycle riding training aiding device - Google Patents

Abstract

The invention relates to a bicycle riding training aiding device comprising pedal sensors, an encoder and a sensor system signal processor. The encoder is installed on the outer end of a pedal shaft; the pedal sensors are arranged on a left pedal and a right pedal of a tested bicycle; each pedal sensor comprises an X-direction differential capacitor unit combination and a Y-direction differential capacitor unit combination. Each of the X-direction differential capacitor unit combination and the Y-direction differential capacitor unit combination comprises more than two capacitor unit modules forming differential action mutually. Each capacitor unit module is of a comb-shaped structure formed by combining more than two strip capacitor units. The bicycle riding training aiding device can provide theoretical foundation for determination of the sitting position suitable of the characteristics of the body structure of a trainer and determination of the optimal frame structure and size for each tested bicyclist.

Description

Cycling motion supplemental training device

Technical field

The invention belongs to athletic training technical field, relate to training cycles project, be specifically related to a kind of cycling motion supplemental training device.

Background technology

In cycling, scrunching is the sole power that people and car advance, good step on juggling with the feet art sportsman can be made to obtain maximum power with minimum energy ezpenditure, and fall behind, the stepping on juggling with the feet art and too can consume athletic physical efficiency of mistake, but can not get corresponding effect.From the geometry of bicycle, when riding, driver and bicycle contacts position only have three places: handlebar, car are sat and pedal.Therefore foot, buttocks and the relative position of arm on bicycle determine the transmission of comfort level and the active force of riding.Such as, the angle between foot pedal and crank axle, can affect trainer's pin and act on normal force on pedal and the tangential force component size along effective force and inefficacious direction, affect virtuous functioning efficiency.Therefore, be necessary to monitor the active force of motion process mesopodium, buttocks and arm, help trainer to adjust riding posture, and train the best to step on juggling with the feet art.

Summary of the invention

In order to overcome the deficiencies in the prior art, the invention provides a kind of cycling motion supplemental training device, by monitoring appearance position, experimenter upper body, change sit angle, the pedal caused by sitting height, car are sat, hand the change of upper kinetic parameter, thus for the sitting posture location that is suitable for trainer's organization of human body characteristic and provide theoretical foundation and effective initial data for surveyed each cyclist obtains body frame structure for automotive size optimum separately.

Technical scheme of the present invention is: a kind of cycling motion supplemental training device, comprise pedal sensor, encoder and sensor system signals processor, encoder is arranged on the outer end of crank shaft, for obtain any time crank and pedal between angle β, solve the effective force along the axial inefficacious and vertical direction of crank, pedal sensor is arranged on the left and right pedal of test carriage, obtain the three-dimensional force acted on pedal, described pedal sensor comprises X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination, described X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination include two or more and mutually form differential capacitor cell module, described capacitor cell module adopts the comb structure be made up of plural strip capacitor cell, each strip capacitor cell comprises the drive electrode of top crown and the induction electrode of bottom crown, the normal force of the capacitance read group total sensor of described X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination and eliminate tangential force impact.

Cycle test car supplemental training assembling device also comprises handlebar sensor and vehicle seat sensor, for monitoring the three-dimensional active force on vehicle seat and handlebar, obtains the distribution of weight of upper body and the firmly feature of trunk-hand.The drive electrode of each strip capacitor cell is identical with induction electrode width, and the length of drive electrode is greater than induction electrode length, and drive electrode length two ends are reserved left poor position δ respectively _leftwith right poor position δ _right, b _{0 drives}=b _{0 sense}+ δ _right+ δ _left, wherein, b _{0 drives}for the drive electrode length of strip capacitor cell, b _{0 sense}for the induction electrode length of strip capacitor cell.Described poor position δ _left=δ _right, and wherein d ₀for elastic fluid thickness, G is the modulus of rigidity of elastic fluid, τ _maxfor maximum stress value.Described two groups of drive electrodes mutually forming the strip capacitor cell of differential capacitor cell module and induction electrode are provided with the skew that initially misplaces in the width direction, and dislocation bias size is identical, direction is contrary.The lead-in wire that described comb teeth-shaped structure comprises more than 20 strip capacitor cells, connects one to one with strip capacitor cell, is provided with electrode spacing a between adjacent two strip capacitor cells _δ.Described parallel-plate area S=M (a ₀+ a _δ) b ₀, wherein, M is strip capacitor cell quantity, b ₀for the length of strip capacitor cell, a ₀the width of strip capacitor cell.The lead-in wire of each strip capacitor cell of described capacitor cell module is by parallel connection or be independently connected to sensor-based system signal processor.The width of described strip capacitor cell wherein, d ₀for elastic fluid thickness, E is the Young's modulus of elastic fluid, and G is the modulus of rigidity of elastic fluid.Be provided with intermediate translator between described sensor-based system signal processor and capacitor cell module, intermediate translator is for arranging voltage to electric capacity or frequency to the transmission coefficient of electric capacity.

The present invention has following good effect: cycle test car supplemental training device of the present invention, by monitoring appearance position, experimenter upper body, change sit angle, the pedal caused by sitting height, car are sat, hand the change of upper kinetic parameter, find the sitting posture location that is suitable for trainer's organization of human body characteristic and provide theoretical foundation for surveyed each cyclist obtains body frame structure for automotive size optimum separately.The present invention, on the basis of capacitance measurement three-dimensional force, effectively uses platen area, and is effectively solved between three-dimensional force by the method such as differential and be coupled, thus makes normal direction and tangential conversion all reach higher linear, precision and sensitivity.

Accompanying drawing explanation

Fig. 1 is strip capacitor cell and the coordinate system thereof of the specific embodiment of the present invention.

Fig. 2 is the strip capacitor cell schematic diagram of the specific embodiment of the present invention.

Fig. 3 is the strip capacitor cell dextrad skew schematic diagram of the specific embodiment of the present invention.

Fig. 4 is the strip capacitor cell left-hand skew schematic diagram of the specific embodiment of the present invention.

Fig. 5 is the right initial dislocation figure of the strip capacitor cell of the specific embodiment of the present invention.

Fig. 6 is that the strip capacitor cell of the specific embodiment of the present invention is to stressed rear deflection graph.

Fig. 7 is the parallel-plate three-dimensional force pressure sensor structure figure of the specific embodiment of the present invention.

Fig. 8 is the parallel-plate three-dimensional force pressure sensor drive electrode structure chart of the specific embodiment of the present invention.

Fig. 9 is the parallel-plate three-dimensional force pressure sensor induction electrode structure chart of the specific embodiment of the present invention.

Figure 10 is that being exported by identical carry-over factor K realization of the specific embodiment of the present invention responds summation.

Figure 11 is the differential schematic diagram of signal that the cell capacitance of the specific embodiment of the present invention is right.

Figure 12 is the plane-parallel capacitor cross-section structure of the specific embodiment of the present invention.

Figure 13 is the foot-operated upper stressing conditions analysis chart of the car of the specific embodiment of the present invention.

Wherein, 1, upper PCB substrate, 2, lower PCB substrate, 3, drive electrode, 4, induction electrode, 5, elastic fluid.

Detailed description of the invention

Contrast accompanying drawing below, by the description to embodiment, the specific embodiment of the present invention is as the effect of the mutual alignment between the shape of involved each component, structure, each several part and annexation, each several part and operation principle, manufacturing process and operation using method etc., be described in further detail, have more complete, accurate and deep understanding to help those skilled in the art to inventive concept of the present invention, technical scheme.

As shown in figure 13, be the foot-operated upper stressing conditions analysis chart of cycle test car, the left side is crank coordinate system, and the right, for acting on the force analysis on pedal, after pedal three-dimensional force tests out, for terrestrial coordinate system, will act on the normal force (F on pedal _pn) and tangential force (F _pt) along the Directional Decomposition that crank axle is parallel and vertical with crank axle time, record according to encoder corresponding moment foot pedal and crank axle between angle β, so just can in the hope of the component along crank axle parallel direction, also namely inefficacious, and the component in the direction vertical with crank axle, be also effective force, effective force is exactly functioning efficiency with the ratio of making a concerted effort, functioning efficiency is the evaluation index spoiling juggling with the feet art, and to spoil juggling with the feet art be control posture, load and spoil the embodiment directly perceived pedaling frequency.Therefore, test carriage left and right pedal installs three-dimensional force sensor, monitoring pin acts on tangential force on pedal and normal force, high and spoil and pedal frequency by changing seat angle, seat, act on tangential force on pedal and normal force binding mode can change, in the outer end of crank shaft, encoder is installed, the angle between acquisition any time crank and pedal.

Also loading onto three-dimensional force sensor under a car seat with under handlebar, for monitoring the active force on vehicle seat and handlebar, thus seeking the distribution of weight of upper body and the stability features of trunk-hand when changing the amount of riding.The active force feature at comprehensive three places guarantees that the best rides reasonability and the science of appearance location.Handlebar, vehicle seat, left and right pedal three-dimensional force sensor and the 15 road signals such as left and right pedal encoder and sampling time sequence are nursed one's health in signal conditioner, through ADC conversion laggard enter microprocessor.Microprocessor simultaneously control synchronization luminous point (with realize kinematics, kinetic measurement synchronous), and to be connected with PC by USB interface.Software can realize from functions such as data acquisition, data processing, data storage and data readbacks.

Effective force, inefficacious and can try to achieve according to following formula with joint efforts accordingly: F _{effective force}=-F _ptcos β+F _pnsin β; F _{inefficacious}=-F _ptsin β+F _pncos β;

The measuring principle of three-dimensional force sensor of the present invention is below described: sensor of the present invention comprises X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination, described X-direction differential capacitor unit combination is passed through the tangential force of capacitance subtraction calculations X-direction and is eliminated the impact of Y-direction tangential force, described Y-direction differential capacitor unit combination is passed through the tangential force of capacitance subtraction calculations Y-direction and is eliminated the impact of X-direction tangential force, the normal force of the capacitance read group total capacitance sensor of described X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination and eliminate tangential force impact.Described X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination include two or more and mutually form differential capacitor cell module, described capacitor cell module adopts the comb teeth-shaped structure be made up of plural strip capacitor cell, and each strip capacitor cell comprises the drive electrode of top crown and the induction electrode of bottom crown.The drive electrode of described each strip capacitor cell is identical with induction electrode width, and the length of drive electrode is greater than induction electrode length, and drive electrode length two ends are reserved left poor position δ respectively _leftwith right poor position δ _right, b _{0 drives}=b _{0 sense}+ δ _right+ δ _left, wherein, b _{0 drives}for the drive electrode length of strip capacitor cell, b _{0 sense}for the induction electrode length of strip capacitor cell.Described poor position δ _left=δ _right, and wherein d ₀for elastic fluid thickness, G is the modulus of rigidity of elastic fluid, τ _maxfor maximum stress value.Described two groups of drive electrodes mutually forming the strip capacitor cell of differential capacitor cell module and induction electrode are provided with the skew that initially misplaces in the width direction, and dislocation bias size is identical, direction is contrary.The lead-in wire that described comb teeth-shaped structure comprises more than 20 strip capacitor cells, connects one to one with strip capacitor cell, is provided with electrode spacing a between adjacent two strip capacitor cells _δ.Described parallel-plate area S=M (a ₀+ a _δ) b ₀, wherein, bar M is strip capacitor cell quantity, b ₀for the length of strip capacitor cell, a ₀the width of strip capacitor cell.The lead-in wire of each strip capacitor cell of described capacitor cell module is by parallel connection or be independently connected to sensor-based system signal processor.The width of described strip capacitor cell wherein, d ₀for dielectric thickness, E is the Young's modulus of elastic fluid, and G is the modulus of rigidity of elastic fluid.Be provided with intermediate translator between described sensor-based system signal processor and capacitor cell module, intermediate translator is for arranging voltage to electric capacity or frequency to the transmission coefficient of electric capacity.

1, the transfer characteristic of strip capacitor cell

(1) pumping signal and coordinate system

Strip capacitor cell is placed in the rectangular coordinate system shown in Fig. 1, pole plate plane length b ₀, width a ₀, elastic fluid thickness d ₀.Three-dimensional simulation puts on the outer surface of capacitor plate, and the contact active force of generation has Fx, Fy and Fz tri-durection components, the action direction of Fx and Fy along X-axis and Y-axis, the action direction of Fz along OZ axle, namely direction, normal direction and tangential stress are a kind of stress tensor, from can the response of output capacitance between the lead-in wire of electrode; Normal stress σ _n=Fn/A, wherein A=a ₀b ₀for pole plate normal direction stress surface, Fn=Fz is normal component; Both side surface produces paired tangential stress τ _x=Fx/A, τ _y=Fy/A.

According to the Hooke's law in Elasticity, σ _nand τ _x, τ _yelastomer all will be made to produce corresponding distortion.Wherein,

${\mathrm{\σ}}_n=E\·{\mathrm{\ϵ}}_n=E\·{\mathrm{\δ}}_n/d_0=\frac{F_n}{A}---\left(1\right)$

$\±{\mathrm{\τ}}_x=\±{\mathrm{\γ}}_x\·G=\±G\·{\mathrm{\δ}}_x/d_0=\±\frac{F_x}{A}---\left(2\right)$

$\±{\mathrm{\τ}}_y=\±{\mathrm{\γ}}_y\·G=\±G\·{\mathrm{\δ}}_y/d_0=\±\frac{F_y}{A}---\left(3\right)$

In formula, E is the Young's modulus (unit: GN/m of elastic fluid ²), G is the modulus of rigidity (unit: GN/m of elastic fluid ²), δ n is the Normal Displacement (unit: μm) of elastic fluid, and δ x and δ y is the relative dislocation (unit: μm) of the upper and lower two-plate of strip capacitor cell, and its sign is pointed to by reference axis and determined.

(2) capacitance equation and input-output characteristic thereof

The initial capacitance of rectangular parallel plate capacitor is:

$C_0=\frac{{\mathrm{\ϵ}}_0\·{\mathrm{\ϵ}}_r\·a_0\·b_0}{d_0}---\left(4\right)$

In formula, ε ₀vacuum medium electric constant is 8.85PF/m, ε _r=2.5 is dielectric relative dielectric constant.D ₀by σ _nexcitation produce relative deformation ε _n=δ _n/ d ₀=σ _n/ E, substitutes into (4) and obtains input-output characteristic

$C_n={\mathrm{\ϵ}}_0.{\mathrm{\ϵ}}_r\frac{a_0\·b_0}{d_0(1-{\mathrm{\ϵ}}_n)}={\mathrm{\ϵ}}_0\·{\mathrm{\ϵ}}_r\frac{a_0\·b_0}{d_0(1-\frac{F_n}{AE})}---\left(5\right)$

(3) linearity under normal stress effect and sensitivity

A, the normal direction linearity

F in (5) formula _nin the denominator, therefore C _n=f (F _n) relation be nonlinear, because of conversion range in maximum σ _nmaxcompared with dielectric resilient constant E, ε _na very little amount, i.e. ε in denominator _n<<1, (5) are omitted the higher-order shear deformation of more than quadratic power by series expansion, and (5) formula can be reduced to:

$C_n=C_0(1+\mathrm{\&epsiv;})=C_0(1+\frac{F_n}{A\&CenterDot;E})---\left(6\right)$

Visible at C _nwith F _ntransfer characteristic in the maximum relative error of the normal direction linearity close to zero.

B, sensitivity

By the definition of normal direction sensitivity

Can linear sensitivity be obtained by (6) formula,

S _n1＝C ₀/AE＝ε ₀ε _r/d ₀E (7)

By (5) formula then

$S_{n2}=\frac{{\mathrm{dC}}_n}{{\mathrm{dF}}_n}=C_0\&CenterDot;\frac{1}{1-2\mathrm{\&epsiv;}}=C_0\&CenterDot;\frac{1}{1-2\frac{F_n}{A\&CenterDot;E}}---\left(8\right)$

S _n2with F _nand become, F _nlarger, S _n2larger, in mild nonlinear in whole transfer characteristic.

(4) tangential stress τ _xand τ _ycapacitance variations under excitation

Tangential stress τ _xand τ _ydo not change the physical dimension parameter b of pole plate ₀and a ₀, to dielectric thickness d ₀also do not have an impact.But τ _xand τ _ychange the space structure of plane-parallel capacitor, between the upper bottom crown faced by forward, there occurs dislocation skew.Now for OX direction, pole plate is at τ _xdislocation skew δ under effect _x.

Work as τ in fig. 2 _xwhen being zero, a _{on 0}=a _{0 time}just right, effective cross-section A between substrate _τ=a ₀b ₀; In figure 3, at τ _xunder the effect of dextrad, top crown creates dislocation skew δ to the right relative to bottom crown _x, thus make the effective area A between bottom crown when calculating electric capacity _τ=(a ₀-δ _x) b ₀; In Fig. 4, work as τ _xduring for left-hand, dislocation skew δ _xthen left, A _τ=(a ₀-δ _x) b ₀, the reduction of effective area is identical, and consequent electric capacity is:

$C_{\mathrm{\&tau;}x}=\frac{{\mathrm{\&epsiv;}}_0.{\mathrm{\&epsiv;}}_r\&CenterDot;(a_0\&CenterDot;{\mathrm{\&delta;}}_x)\&CenterDot;b_0}{d_0}---\left(9\right)$

According to shearing Hooke's law

τ _x＝γ _x·G＝G·δ _x/d ₀(10)

(10) are substituted into (9) can obtain

$C_{\mathrm{\&tau;}x}=C_0-\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r\&CenterDot;{\mathrm{\&delta;}}_x\&CenterDot;b_0}{d_0}=C_0-\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r\&CenterDot;b_0{\mathrm{\&tau;}}_x}{G}=C_0-\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r{F}_x}{{\mathrm{Ga}}_0}---\left(11\right)$

(11) formula is input---the output characteristics under shearing stress, C _τwith τ _xlinear.

And its sensitivity

$S_{\mathrm{\&tau;}x}=\frac{{\mathrm{dC}}_{\mathrm{\&tau;}x}}{{\mathrm{dF}}_x}=\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r}{{\mathrm{Ga}}_0}---\left(12\right)$

The similar analysis in formula (9)-(12) is suitable for and τ equally _ywith C _{τ y}characteristic and technical indicator, the only long limit b of strip capacitor cell in formula ₀oX direction of principal axis should be arranged at, and its minor face a ₀then in OY direction.

(5) introduction of differential capacitor unit

Capacitor arrangement change shown in Fig. 3 and Fig. 4, only illustrates that electric capacity exports and tangential stress ± τ _xthe relation of input, capacitance increase is all negative, and therefore this initial capacitance structure is not suitable for as right ± τ _xobtain the response increasing and decreasing electric capacity.The present invention adjusts the initial configuration of bottom crown on capacitor for this reason, forms pair of differential electric capacity to (C _lwith C _r), specifically as shown in Figure 5.

In Fig. 5, a pair electric capacity C _land C _relectrode size a ₀, b ₀, d ₀all identical, initial dislocation skew δ ₀also identical, difference is left side capacitor C _lupper strata δ ₀wedge angle be oriented to+OX, and the right capacitor C _rupper strata δ ₀wedge angle sensing-OX.

Work as τ _xwhen=0, namely the electric capacity in figure corresponding to dash area, on this basis as at-F _xlower generation ± the δ of excitation _xmistake skew, formed as shown in Figure 6 electric capacity increase and decrease effect.

$C_L=\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r\&CenterDot;b_0\&CenterDot;(a_0-{\mathrm{\&delta;}}_0\&PlusMinus;{\mathrm{\&delta;}}_x)}{d_0}---\left(13\right)$

C in Fig. 6 _land C _rdifferential capacitor is to same τ _xby generation ± δ _xwith ± Δ C _τresponse.

δ ₀size should meet desirable δ ₀=10 μm, thus, formula (11) can be revised as

$C_{\mathrm{\&tau;}x}=C_{\mathrm{\&tau;}0}\&PlusMinus;\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r}{{\mathrm{Ga}}_0}{F}_x---\left(14\right)$

In formula, for initial capacitance when shearing stress is zero, (14) formula is shearing stress input-output characteristic, C _{τ x}with F _xlinear relationship, and its sensitivity

2, contact parallel plate capacitor design

(1) planar design of parallel plate capacitor

Arrange, at a 10 × 10mm see the electrode plane in Fig. 7, Fig. 8 and Fig. 9 ²substrate center do cross separate, form four quadrants I, II, III, IV, wherein I, II quadrant is to τ _xmake the differential capacitor unit combination of response, and III, IV quadrant is to τ _ymake the differential capacitor unit combination of response.Object-line is 10 × 10mm ²pcb board four edge lines, answer precise cutting accurate with what ensure in shape and size to PCB substrate.Hachure part represents the outer mode cross section of wax-loss casting process, and its geometry and size also should keep precisely when mechanical-moulded, tears open, more should maintain dimensional accuracy for being convenient in demoulding and can spelling, finally to ensure the mutual interference that elimination three-dimensional force responds electric capacity.

Capacitor cell module adopts the comb teeth-shaped structure be made up of plural strip capacitor cell, and each strip capacitor cell comprises the drive electrode of top crown and the induction electrode of bottom crown.By formula (12) a ₀less, the sensitivity of tangential stress response is larger, therefore single electric capacity is strip.If every root strip capacitor cell is wide is a ₀, the groove width between two strip capacitor cells is a _δ, then the pitch of every root strip capacitor cell is a ₀+ a _δ.In order to make full use of the plane space of square substrate, make M (a ₀+ a _δ) b ₀≈ 1 square substrate surface area, M is the strip capacitor cell number in 4 quadrants, then have M (a ₀+ a _δ)=2*10mm, in formula, groove width a _δunsuitable excessive, otherwise be unfavorable for using the effective plane space on substrate, also unsuitable too small, the constraint of wax-loss casting process is subject to.For making normal direction sensitivity S _nwith tangential sensitivity S _τidentical, by formula (7) and (12), make a ₀g=d ₀e, works as d ₀during=0.1mm, then a ₀=0.15mm, if make a _δ=0.05mm, then M=100, each quadrant has 25 strip capacitor cells.

In order to realize τ _xand τ _ymutually do not have an impact between tangential response, δ is reserved at drive electrode length two ends ₀, therefore b _{0 drives}=b _{0 end}+ 2 δ ₀, wherein at b _{0 drives}two ends length is reserved should be ensured in theory its calculated value is therefore should b be ensured in technique _{0 drives}-b _{0 end}>=0.01mm.τ can be ensured like this when computing method exports response to electric capacity _xand τ _yany impact is not produced on the response of normal direction electric capacity.

In order to realize τ _xand τ _yany impact is not produced on the response of normal direction electric capacity, drive electrode and the horizontal layout of induction electrode in all quadrants of each strip capacitor cell should ensure that certain dislocation offsets, eliminated the effects of the act by differential, get the position of induction electrode in lower floor's PCB substrate as reference, then the layout of drive electrode in the PCB substrate of upper strata should with PCB substrate edge line for benchmark.In figure, four dashed rectangle are the benchmark of induction electrode on bottom crown.And put they and geometry datum line differential apart from being δ ₀(0.1mm), to ensure τ _xproduce differential capacitor at I, II quadrant capacitor cell and export response, then produce τ at III, IV quadrant capacitor cell _ydifferential capacitor response, an initially dislocation skew δ is set _xo, its value should ensure its calculated value and δ ₀similar, its skew that initially misplaces all arranges δ _xo=δ _yo=0.01mm, to ensure that capacitor cell in four quadrants is at τ _xand τ _ytwo groups of differential capacitors pair can be produced under tangential excitation.C in figure 6 _{τ xI}=C _rand C _{τ xII}=C _lfor conversion τ _xdifferential capacitor pair, and C _{τ xIII}=C _land C _{τ xIV}=C _rbe then conversion τ _ydifferential capacitor pair.

(2) normal stress calculates

The normal direction can being rewritten single capacitor by formula (6) responds electric capacity

$C_{ni}=N(C_0+\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_{r\&CenterDot;Fn}}{d_{0}E})---\left(15\right)$

Wherein, i=I, II, III, IV, because of in each quadrant, N refers to the quantity of the strip capacitor cell of each quadrant, and N number of strip capacitor cell is in parallel.

As sued for peace again, can obtain

Above formula is σ _nelectric capacity overall response.

Although the summation of single electric capacity is connected in parallel realization by contact conductor.But once and connect, just no longer can realize asking subtractive combination, the summation combination on historical facts or anecdotes border will be sued for peace by the output of intermediate translator again, sees Figure 10, the signal flow block diagram of summation

In figure, intermediate translator K can be voltage to electric capacity or frequency to the transmission coefficient of electric capacity, thus completes the synthesis to normal direction response.

$O_n=4KN(C_0+\frac{{\mathrm{\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r\&CenterDot;Fn}{d_{0}E})---\left(16\right)$

(3) tangential stress calculates

C _ito C _iIand C _iIIto C _iVtwo can be realized to differential combination, see Figure 11, through differential technique process, the overall response of differential output

$O_{\mathrm{\&tau;}x}=\frac{2{\mathrm{NK\&epsiv;}}_0\&CenterDot;{\mathrm{\&epsiv;}}_r}{a_{0}G}{F}_x---\left(17\right)$

In above formula, no matter be normal direction excitation F _nor tangentially encourage F _yall not to O _{τ x}have an impact.Namely automatically σ is eliminated _nand τ _yto τ _xthe coupling of total output or interference comprise at signal because every in the computing of subtracting each other, equivalent and all automatically eliminating with the capacitance variations met.And F _yand F _xto σ _ninterference by upper electrode at b ₀direction increases geometrical length 2 δ ₀eliminate, O _{τ y}in like manner can ask.

(4) main material selection and characterisitic parameter thereof

The pole plate of comb teeth-shaped plane-parallel capacitor is apart from d ₀=0.1mm, upper and lower base plate inner space, except copper foil electrode, is PDMS (dimethyl silicone polymer) the superlastic dielectric with lost wax process filling.Its machinery and physical characteristic parameter are Young's modulus E=6.2MPa, and its shear modulus is G=4.1MPa, relative permittivity ε during dielectric polorization _γ=2.5.Because E and G of medium is much smaller than the elastic modulus E of copper _copper=103GPa.Therefore the distortion of capacitor internal medium under stress state is much larger than the distortion of pole plate.

(5) contact conductor design

Be that drive electrode or induction electrode all need to have lead-out wire, consider that each drive electrode is all ground connection in signal level, therefore four groups of drive electrodes only need share same lead-out wire.Four capacitor cell module induction electrodes then need, with respective independently lead-out wire, to draw, so that whole assembly top and bottom outer surface can contact with measuring object easily so whole capacitance component has at least 5 pins from the side of planar package.

The present invention, under the support of new material and new technology, completes the design of a kind of novel three-dimensional power sensitization capacitance combination, at 10 × 10mm ²stress surface on, be no matter normal direction or tangential, all can transmit stress more uniformly to medium.In literary composition, four cell capacitance are two to combination distribution.In the contact of non-coplanar force and sensor surface, external force only has 1, and electric capacity response but has 4, can obtain normal direction F to 4 electric capacity summations _ninformation, namely whole battery lead plate is all to asking F _ncontribute, simultaneously by two pairs of capacitor combination composition differential systems, can F be obtained again _xand F _yinformation, thus complete description three-dimensional force.

By changing seat angle, seat is high, directly can measure man-vehicle system contact position (pedal, handlebar and vehicle seat) stressed, encoder on crank shaft can be followed the tracks of the angle between crank with pedal and measure synchronous with three-dimensional force, so just acts on effective force on pedal by calculating to try to achieve.By Microprocessor S3C44B0X synchronous light-emitting point, what realize that kinetic measurement and kinematics test is synchronous, the kinematics and dynamics parameter of its test gained is together incorporated to bicycle and steps in juggling with the feet art diagnostic feedback systems soft ware, thus realizes data sampling and processing, storage and playback integration.

Above by reference to the accompanying drawings to invention has been exemplary description; obvious specific implementation of the present invention is not subject to the restrictions described above; as long as have employed the improvement of the various unsubstantialities that method of the present invention is conceived and technical scheme is carried out; or design of the present invention and technical scheme directly applied to other occasion, all within protection scope of the present invention without to improve.

Claims (10)

1. a cycling motion supplemental training device, it is characterized in that, comprise pedal sensor, encoder and sensor system signals processor, encoder is arranged on the outer end of crank shaft, for obtain any time crank and pedal between angle β, solve the effective force along the axial inefficacious and vertical direction of crank, pedal sensor is arranged on the left and right pedal of test carriage, the three-dimensional force that acquisition acts on pedal also sends to sensor-based system signal processor, described pedal sensor comprises X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination, described X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination include two or more and mutually form differential capacitor cell module, described capacitor cell module adopts the comb structure be made up of plural strip capacitor cell, each strip capacitor cell comprises the drive electrode of top crown and the induction electrode of bottom crown, the normal force of the capacitance read group total sensor of described X-direction differential capacitor unit combination and Y-direction differential capacitor unit combination and eliminate tangential force impact.

2. cycling motion supplemental training device according to claim 1, it is characterized in that, described device also comprises handlebar sensor and vehicle seat sensor, for monitoring the three-dimensional active force on vehicle seat and handlebar, obtains the distribution of weight of upper body and the firmly feature of trunk-hand.

3. cycling motion supplemental training device according to claim 2, it is characterized in that, the drive electrode of described each strip capacitor cell is identical with induction electrode width, and the length of drive electrode is greater than induction electrode length, and drive electrode length two ends are reserved left poor position δ respectively _leftwith right poor position δ _right, b _{0 drives}=b _{0 sense}+ δ _right+ δ _left, wherein, b _{0 drives}for the drive electrode length of strip capacitor cell, b _{0 sense}for the induction electrode length of strip capacitor cell.

4. cycling motion supplemental training device according to claim 3, is characterized in that, described poor position δ _left=δ _right, and wherein d ₀for elastic fluid thickness, G is the modulus of rigidity of elastic fluid, τ _maxfor maximum stress value.

5. cycling motion supplemental training device according to claim 2, it is characterized in that, described two groups of drive electrodes mutually forming the strip capacitor cell of differential capacitor cell module and induction electrode are provided with the skew that initially misplaces in the width direction, and dislocation bias size is identical, direction is contrary.

6. cycling motion supplemental training device according to claim 2, it is characterized in that, the lead-in wire that described comb teeth-shaped structure comprises more than 20 strip capacitor cells, connects one to one with strip capacitor cell, is provided with electrode spacing a between adjacent two strip capacitor cells _δ.

7. cycling motion supplemental training device according to claim 6, is characterized in that, described parallel-plate area S=M (a ₀+ a _δ) b ₀, wherein, M is strip capacitor cell quantity, b ₀for the length of strip capacitor cell, a ₀the width of strip capacitor cell.

8. cycling motion supplemental training device according to claim 6, is characterized in that, the lead-in wire of each strip capacitor cell of described capacitor cell module is by parallel connection or be independently connected to sensor-based system signal processor.

9. cycling motion supplemental training device according to claim 2, is characterized in that, the width of described strip capacitor cell wherein, d ₀for elastic fluid thickness, E is the Young's modulus of elastic fluid, and G is the modulus of rigidity of elastic fluid.

10. cycling motion supplemental training device according to claim 2, it is characterized in that, be provided with intermediate translator between described sensor-based system signal processor and capacitor cell module, intermediate translator is for arranging voltage to electric capacity or frequency to the transmission coefficient of electric capacity.