JP3810567B2 - Legged mobile robot - Google Patents

Description

【００５３】
【数２】

【００５４】
ｇ（ｔ）は時刻ｔ₁ から時刻ｔ₂ までの歩行（大負荷作動）を行うときの理想的な水素生成量の推移を示し、ｈ（ｔ）は時刻ｔ₁ の予測遅れ時間Ｔ_s 前の時刻ｔ₀ からｔ_w （ｔ_w −ｔ₀ ＝ｔ₂ −ｔ₁ ＝歩行時間）まで、水素供給量をＡ₁ とする指示を与えたときに、１次遅れ要素と想定した改質器９による水素生成量の推移を示している。グラフ（ｃ）の▲１▼と、▲２▼の部分の面積は、それぞれ、
【００５５】
【数３】

【００５６】
【数４】

【００５７】
となる。改質器９による水素の生成量と、燃料電池５による水素の消費量とのバランスから、▲１▼＝▲２▼とおいて、ｔ₁ を求めると、
【００５８】
【数５】

【００５９】
となる。ここでｔ_w ≫τと想定できるので、
【００６０】
【数６】
ｔ₁ ≒τ ・・・・・（６）
となる。
【００６１】
そこで、発電管理手段７は、時定数τを準備時間Ｔ_s とする。即ち、図２のグラフ（ｅ）を参照して、時刻ｔ₀ で増加指示を行ってから準備時間Ｔ_s が経過した時刻ｔ₁ で、作動制御手段２に対して前記ＥＮＡＢＬＥ信号を送信する。このとき、１次遅れ要素と想定した改質器９の水素生成量は点線で示したように推移し、時刻ｔ₁ での水素生成量は、Ａ₀ ＋（Ａ₁ −Ａ₀ ）×６３．２％（本発明の目標生成量に相当する）となる。この結果、図２のグラフ（ｃ）の▲１▼の領域が余剰の水素発生量となり、同じ面積の▲２▼の領域がこの余剰分を使うこととなり、ロボット１の歩行には支障はない。
【００６２】
そして、発電管理手段７は、歩行終了時刻ｔ₂ の準備時間Ｔ_s 前の時刻であるｔ_w で水素生成量の指示値をＡ₁ からＡ₀ に低下させる。これにより、図２のグラフ（ｄ）を参照して、歩行停止後にリザーブタンク１２の圧力が上がり過ぎることを防止することができる。
【００６３】
尚、改質器９の遅れ時間が大きいときには、図２のグラフ（ｆ）に示したように、Ａ₁ を越えるＡ₂ まで、水素生成量を増加させる指示を与えることで、改質器９による水素生成量が前記目標水素生成量Ｓ_a まで増加するのに要する時間を短縮するようにしてもよい。
【００６４】
次に、図４，図５を参照して、上述した発電管理手段７により、準備時間Ｔ_s を算出して改質器９による水素生成量を制御したときの、リザーブタンク１２内の圧力変化を低減する効果について説明する。図４のグラフ（ａ），（ｂ），（ｃ）は従来の手法によりロボット１の歩行を行ったときのリザーブタンク１２内の圧力変化、グラフ（ｄ），（ｅ），（ｆ）は準備時間Ｔ_s を前記時定数τとしたとしてロボット１の歩行を行ったときのリザーブタンク１２内の圧力変化、図５のグラフ（ｇ），（ｈ），（ｉ）は準備時間Ｔ_S を前記時定数τよりも短くしてロボット１の歩行を行ったときのリザーブタンク１２内の圧力変化をそれぞれ説明するものである。
【００６５】
従来の手法においては、図４を参照して、グラフ（ａ）における水素生成量を増加させる時刻ｔ₀ と、グラフ（ｂ）におけるロボット１が歩行を開始する時刻ｔ₁ とは同じである。その結果、歩行開始後しばらくは、グラフ（ａ）に示した改質器９による水素生成量の実際値よりも、グラフ（ｂ）に示した燃料電池５の水素消費量のほうが多くなり、グラフ（ｃ）に示したようにリザーブタンク１２内の圧力が大きく下がって、ロボット１の動作に最低限必要なリザーブタンク１２の圧力である最低動作圧力を下回る。この場合は、燃料電池５に対する水素供給量が減少して発電量不足の原因となる。
【００６６】
また、歩行停止時には、グラフ（ａ）に示した水素生成量の実際値がグラフ（ｂ）に示した水素消費量を上回るため、グラフ（ｃ）に示したように、リザーブタンク１２内の圧力がリザーブタンク１２の仕様から定める限界最高圧力を越える場合が生じて好ましくない。そして、これらの問題を回避するために、リザーブタンク１２の容量を増やしたときは、リザーブタンク１２の大型化、重量増加を伴うという不都合を生じる。
【００６７】
そこで、図４に示した例においては、グラフ（ｄ）の時刻ｔ₀ で水素の生成量を増加させる指示を行ってから、グラフ（ｅ）に示したように、準備時間Ｔ_S が経過した時刻ｔ₁ でロボット１の歩行を開始する。尚、準備時間Ｔ_S は上述したように、改質器９を１次遅れ要素とみなしたときの時定数τに設定される。このようにロボット１の歩行開始タイミングを遅らせることで、グラフ（ｆ）に示したように、リザーブタンク１２の圧力変動を上述した従来例のグラフ（ｃ）に比べて低減することができる。そのため、リザーブタンク１２の小型化、軽量化が可能である。
【００６８】
また、図５において、グラフ（ｈ）は、グラフ（ｇ）に示した準備時間Ｔ_S を上述した時定数τよりも短い時間に設定する。その結果、グラフ（ｉ）に示したように、リザーブタンク１２の圧力変化を図４のグラフ（ｆ）に示した前記第１の圧力変動低減手法による場合よりもさらに小さくすることができる。そのため、リザーブタンク１２のより小型化、軽量化が可能である。この場合、準備時間Ｔ_S は、
Ｔ_S ＝時定数（τ）×定数（１以下）
で表され、歩行開始時と歩行停止時のそれぞれに対して適用される。準備時間Ｔ_S は、さらに必要に応じて精密に設定することも可能であり、
Ｔ_S ＝ｆ（現在圧力，目標生成変化量，目標圧設定値，圧力上限値，圧力下限値，時定数）
により、リザーブタンク１２内の圧力が圧力上限値（本発明の所定の上限圧に相当する）を越えないように算出してもよい。ここで、現在圧力はリザーブタンク１２の現在の圧力、目標圧設定値はリザーブタンク１２の圧力の目標値であり、目標生成変化量と共に、入力変数である。それら以外はパラメータであり、時定数は図２で説明した改質器９を１次遅れとみなしたときの時定数である。例えば、現在圧力が高い場合には、リザーブタンク１２内の水素量は十分であるので、準備時間Ｔ_S をより短い時間に設定してもかまわない。尚、準備時間Ｔ_S をこのように関係式から算出する他、予め実験で求めたデータテーブル等により算出するようにしてもよい。
【００６９】
続いて、本発明の第１の実施の形態における発電管理手段７（図１参照）の具体的な動作について、シーケンスマネージャ２４の動作を中心として、図１に示した全体構成図を参照しつつ、図６に示したフローチャートと図７，図８に示したタイムチャートにより説明する。尚、図７，図８において、グラフ（ａ）はシーケンスマネージャ２４の作動状態の遷移、グラフ（ｂ）は作動制御手段２から指示される行動計画（ここでは歩行計画）の内容、グラフ（ｃ）は燃料電池５の水素消費量（ロボット１の消費電力に対応する）の推移、グラフ（ｄ）は改質器９の水素生成量の推移、グラフ（ｅ）は作動制御手段２に対する制御信号（ＥＮＡＢＬＥ／ＩＮＨＩＢＩＴ）の出力の変化をそれぞれ表している。
【００７０】
図６のフローチャートを参照して、シーケンスマネージャ２４は、ＳＴＥＰ１〜ＳＴＥＰ６のルーチンを繰り返し実行する。ＳＴＥＰ１〜ＳＴＥＰ６のルーチンにおいては、シーケンスマネージャの作動状態は、作動制御手段２からの歩行計画の指示を待っている状態である「歩行計画変更待ち状態」、作動制御手段２からの歩行計画の指示を受け取ってから、改質器生成量指示手段２５を介して改質器９に対する水素生成量の変更指示を行うタイミングを待っている状態である「改質生成指示待ち状態」、及び改質器９に対して水素生成量の変更指示を行ってから、前記準備時間Ｔ_S が経過するのを待っている状態である「改質生成先行状態」の３種類の状態のいずれかとなる。
【００７１】
「歩行計画変更待ち状態」にあるときは、シーケンスマネージャ２４は、ＳＴＥＰ２からＳＴＥＰ１０に分岐し、ＳＴＥＰ１０で作動制御手段２から歩行計画の変更リクエストがあったときは、ＳＴＥＰ１１に進んで、作動制御手段２から歩行計画の内容（歩行開始、歩行停止等の指示）を受け取り、「改質生成指示待ち状態」に移行する。一方、ＳＴＥＰ１０で作動制御手段２から歩行計画の変更リクエストがなかったときには、「歩行計画変更待ち状態」が維持される。
【００７２】
「改質生成指示待ち状態」にあるときは、シーケンスマネージャ２４は、ＳＴＥＰ３からＳＴＥＰ２０に分岐し、ＳＴＥＰ２０で前記準備時間Ｔ_S を算出する。そして、ＳＴＥＰ２１で現在時刻ｔが歩行計画開始の指示時刻ｔ_P のＴ_S 時間前になったとき（ｔ≧ｔ_P −Ｔ_S ）にＳＴＥＰ２２に進んで、改質器生成量指示手段２５により改質器９に対する水素の生成量を計算して改質器９に指示する。そして、続くＳＴＥＰ２３でシーケンスマネージャ２４は、作動制御手段２に対してＩＮＨＩＢＩＴ信号を出力して作動制御手段２の動作変更を禁止して、「改質生成先行状態」に移行する。
【００７３】
「改質生成先行状態」にあるときは、シーケンスマネージャ２４は、ＳＴＥＰ４で、「改質生成先行状態」に移行してから前記準備時間Ｔ_S が経過した時に、ＳＴＥＰ５に進んで作動制御手段２にＥＮＡＢＬＥ信号を送信する。このＥＮＡＢＬＥ信号の受信により、作動制御手段２は要求があった歩行計画を実行する。そして、シーケンスマネージャ２４は、「歩行計画変更待ち状態」に移行する。
【００７４】
尚、ＥＮＡＢＬＥ信号とは、作動制御手段２によるロボット１の動作の変更制御を許可する意味を持つ信号であり、歩行そのものを許可する意味を持つものではない。即ち、シーケンスマネージャ２４から作動制御手段２にＥＮＡＢＬＥ信号が出力されているときは、ロボット１の動作の変更が許可され、作動制御手段２は、例えば歩行中のロボット１を停止させる制御を行うことができる。一方、ＥＮＡＢＬＥ信号が出力されていないときには、ロボット１の動作変更が禁止され、例えばロボット１が歩行中であれば、ロボット１は歩行を継続する。
【００７５】
以上説明した図６のフローチャートにより、脚式移動ロボット１を作動させる具体例を図７，図８のタイムチャートを参照して説明する。
【００７６】
図７は、シーケンスマネージャ２４が作動制御手段２から歩行計画を受け取ってから、実際に脚式移動ロボット１の歩行を開始するまでに待ち時間がある場合の例である。図７を参照して、シーケンスマネージャ２４は「歩行計画変更待ち状態」（（ａ）のＳＴ１１）であるときに、作動制御手段２から時刻ｔ_P 1 で歩行を開始する歩行計画の指示（（ｂ）の▲１▼））を受け取ると（（ｃ）の▲２▼）、歩行開始時刻ｔ_P 1 の準備時間Ｔ_S 前の時刻であるｔ_C 1 までの間（Ｔ_w 1 ）、「改質生成指示待ち状態」（（ａ）のＳＴ１２）となる。
【００７７】
そして、時刻ｔ_C 1 で、シーケンスマネージャ２４は、改質器生成量指示手段２５を介して、改質器９に対する水素生成量の指示値を増加させる（（ｄ）の▲３▼）。これにより、（ｄ）に示したように、改質器９の水素生成量が増加する。それと共に、シーケンスマネージャ２４は作動制御手段２にＩＮＨＩＢＩＴ信号を送信して、作動制御手段２の作動を禁止し、「改質生成先行状態」（（ａ）のＳＴ１３）に移行する。
【００７８】
歩行開始時刻ｔ_P 1 になると、シーケンスマネージャ２４は、作動制御手段２にＥＮＡＢＬＥ信号を出力して作動禁止を解除することで、歩行開始指示（（ｄ）の▲５▼）を行う。これにより、作動制御手段２の制御により脚式移動ロボット１が歩行を開始し、シーケンスマネージャ２４は「歩行計画変更待ち状態」（（ａ）のＳＴ２１）に移行する。
【００７９】
そして、シーケンスマネージャ２４は、作動制御手段２から歩行を停止する作動計画の指示（（ｂ）の▲６▼）を受け取ると（（ｃ）の▲７▼）、歩行停止時刻ｔ_P 2 の準備時間Ｔ_S 2 前の時刻であるｔ_C 2 までの間（Ｔ_w 1 ）、「改質生成指示待ち状態」（（ａ）のＳＴ２２）となる。
【００８０】
時刻ｔ_C 2 で、シーケンスマネージャ２４は、改質器生成量指示手段２５を介して、改質器９に対する水素生成量の指示値を減少させて（（ｄ）の▲８▼）、「改質生成先行状態」（（ａ）のＳＴ２３）に移行する。これにより、（ｄ）に示したように、改質器９の水素生成量が徐々に減少する。そして、シーケンスマネージャ２４は、歩行停止時刻ｔ_P 2 で作動制御手段２にＥＮＡＢＬＥ信号を出力することで、歩行停止指示（（ｄ）の▲９▼）を行う。この歩行停止指示を受け取ることで、作動制御手段２の制御により脚式移動ロボット１は歩行を停止する。
【００８１】
このように、作動制御手段２からシーケンスマネージャ２４に脚式移動ロボット１の歩行停止指示がなされてから、実際にロボット１が歩行を停止するまでに、準備時間Ｔ_S 2 の遅れ時間を持たせることで、歩行停止時に改質器９から燃料電池５への水素供給量が過剰となり、リザーブタンク１２内の圧力が異常に上昇することを防止している。
【００８２】
次に、図８は、シーケンスマネージャ２４が作動制御手段２から歩行計画を受け取ると同時又は短時間内に、脚式移動ロボット１の歩行を開始する場合の例である。図８を参照して、シーケンスマネージャ２４は「歩行計画変更待ち状態」（（ａ）のＳＴ１１）であるときに、作動停止手段２から直ちに歩行を開始する作動計画の指示（（ｂ）の▲１▼）を受け取ると（（ｃ）の▲２▼）、直ちに改質器生成量指示手段２５を介して、改質器９に対する水素生成量の指示値を増加させる（（ｄ）の▲３▼）。それと共に、シーケンスマネージャ２４は作動制御手段２にＩＮＨＩＢＩＴ信号を出力し、作動制御手段２の作動を禁止して「改質生成先行状態」（（ａ）のＳＴ１３））に移行する。即ち、図７で説明した「改質生成指示待ち状態」（図７（ａ）のＳＴ１２）にはならない。
【００８３】
これにより、（ｄ）に示したように改質器９の水素生成量が徐々に増加する。そして、シーケンスマネージャ２３は、「改質生成先行状態」に移行してから準備時間ｔ_S 1 が経過した時刻ｔ_q 1 で作動制御手段２にＥＮＡＢＬＥ信号を出力して歩行開始指示を行う（（ｄ）の▲５▼）。即ち、作動制御手段２から脚式移動ロボット１の歩行開始指示がなされてから、実際に脚式移動ロボット１が歩行を開始するまでに、準備時間Ｔ_S 1 の遅れ時間を生じさせることで、歩行開始時に改質器９から燃料電池５への水素供給量が不足して、燃料電池の発電量不足が生じることを防止している。
【００８４】
そして、シーケンスマネージャ２４は、作動制御手段２から歩行を停止する行動計画の指示（（ｂ）の▲６▼）を受け取ると（（ｃ）の▲７▼）、直ちに改質生成量指示手段２５を介して、改質器９に対する水素生成量の指示値を減少させて（（ｄ）の▲８▼）、「改質生成先行状態」（（ａ）のＳＴ２３）に移行する。即ち、歩行開始時と同様に、「改質生成指示待ち状態」になることがない。
【００８５】
これにより、（ｄ）に示したように改質器９の水素生成量は徐々に減少し、シーケンスマネージャ２４は、「改質生成先行状態」（（ａ）のＳＴ２３）となってから、準備時間Ｔ_S 2 が経過した時刻であるＴ_q 2 で、作動制御手段２に対してＥＮＡＢＬＥ信号を出力して歩行停止指示（（ｄ）の▲９▼）を行う。これにより、図７に示した例と同様、歩行停止時に改質器９から燃料電池５への水素供給量が過剰となり、リザーブタンク１２内の圧力が異常に上昇することを防止している。
【００８６】
次に本発明の第２の実施の形態について、図９，図１０を参照して説明する。尚、図１と同じ構成部分については同一の符号を付して説明を省略する。上記第１の実施の形態では、準備時間Ｔ_s により作動制御手段２に対してＥＮＡＢＬＥ信号を送信（歩行開始の指示）するタイミングを決定したが、準備時間Ｔ_s は改質器９を１次遅れ要素と想定して算出したものであるため、実際の改質器９の遅れ時間に対する誤差が大きくなることが考えられる。
【００８７】
そこで、図９を参照して、本発明の第２の実施の形態における発電管理手段７は、改質器９による水素生成量を把握するオブザーバー４０（本発明の燃料生成量把握手段に相当する）を備える。図１０を参照して、オブザーバー４０は、燃料電池５の発電量から水素消費量換算手段２９により算出された燃料電池５の水素消費量と、温度センサ４１により検出される改質器９内の温度と、圧力センサ４２により検出されるリザーブタンク１２内の圧力とを入力して、改質器９による水素生成量を推定する。
【００８８】
即ち、図９を参照して、水素消費量換算手段２９は、燃料電池５の発電量を水素消費量変換率で除して燃料電池５の水素消費量を算出する。そして、図１０を参照して、オブザーバ４０は、水素消費量換算手段２９により算出された燃料電池５の水素消費量と、オブザーバ４０自身の水素発生推定量の前回値との差を入力として、４４でリザーブタンク１２の容積に対応したリザーブタンク１２内の圧力を求め、４５でリザーブタンク１２内の温度を考慮した補正を行う。そして、補正した値と圧力センサ４２によるリザーブタンク１２内の検出圧力との差を４６で求めて、伝達関数Ｈに入力し、伝達関数Ｈの出力を改質器９による今回の水素生成量と推定する。
【００８９】
尚、伝達関数Ｈは、応答性を重視するか推定精度を重視するかに応じて、複数種類を使い分けるようにしてもよい。また、上記の水素消費量換算率は、１／（燃料電池の発電効率）とみなしてもよい。
【００９０】
図９を参照して、発電制御手段７は、加え合せ点４１でリザーブタンク１２の検出圧力と目標圧設定手段２６により設定された圧力目標値（１気圧付近）との差をとり、該差が０となるように演算部４２で指示値を算出する。そして加え合せ点４３では、演算部４２からの指示値と、改質器生成量指示手段２５からの改質器９による水素生成量を増加させる指示値とが加算され、水素消費量換算手段２９により算出された燃料電池５の水素消費量が減算される。
【００９１】
そして、加え合せ点４４では、加え合せ点４３からの指示値から、オブザーバー４０により推定された改質器９による水素生成量が減算され、減算結果が０となるように、即ち、加え合せ点４３からの指示値と、オブザーバー４０により推定される改質器９による水素生成量とが一致するように、演算部４５は改質器９と可変弁１０に対する水素生成量の指示を行う。尚、応答速度を改善するためのフィードフォワード要素４６を追加してもよい。また、４７は図１のスイッチ２８と同様、加え合わせ点４１によるフィードバック制御を中断して、改質器９及び可変弁１０に対する水素生成量の増加指示が該フィードバック制御により制限されることを防ぐためのスイッチである。
【００９２】
このように、オブザーバー４０により、改質器９による水素生成量を推定し、該推定値と水素生成量と水素生成量の指示値との差を求めることにより、水素生成量の増加指示に対する改質器９の実際の水素生成量の増加度合いが小さいときに、増加指示値をさらに増加させる制御が行われる。これにより、オブザーバ４０を使用しない上述した本発明の第１の実施の形態に比べて、図９に示す本実施の形態では、改質器生成量指示手段２５の出力である水素生成量指示値に対して、水素発生量オブザーバ４０を含めて、ローカルフィードバックを形成しており、より応答性が高く、かつ精度の高い水素生成量の制御が期待できる。そのため、前記準備時間Ｔ_S の経過時の、実際の水素発生量がより精度よく予測値に近づき、その結果としてロボット１への電力供給が不足する可能性を低減させることができる。
【００９３】
次に、図１１を参照して、本発明の第３の実施の形態について説明する。上述した第１、第２の実施の形態では、準備時間Ｔ_s を基準に作動制御手段２に対してＥＮＡＢＬＥ信号を送信（歩行開始の指示）するタイミングを決定したが、本第３の実施の形態においては、前記必要水素生成量Ｓ_n に応じて判定基準水素生成量Ｓ_a を決定し、該Ｓ_a を基準として、作動制御手段２に対してＥＮＡＢＬＥ信号を送信（歩行開始の指示）するタイミングを決定する。
【００９４】
即ち、発電管理手段７は、必要水素生成量算出手段２３により必要水素生成量Ｓ_n を算出し、Ｓ_n に応じて判定基準水素生成量Ｓ_a を例えばＳ_n の７０％に決定する。そして、Ｓ_a での水素の生成がなされるように改質器生成量指示手段２５を介して改質器９に対する水素生成量の増加指示を行う。尚、加え合せ点４３より先の制御処理は上記第２の実施の形態と同様である。
【００９５】
そして、シーケンスマネージャ２４は、判定基準水素生成量Ｓ_a とオブザーバー４０により推定した改質器９による水素生成量Ｓ_p とを比較し、Ｓ_p がＳ_a 以上となったときに、作動制御手段２に対して前記ＥＮＡＢＬＥ信号を出力する。これにより、前記第１，第２の実施の形態と同様、ロボット１の歩行開始時（時刻ｔ₁ ）までに、改質器９による水素の生成量を歩行に必要な量まで増加させることができ、歩行開始時に燃料電池５からの電力供給量が不足することを防止することができる。また、リザーブタンク１２の残有圧力に従って判定基準水素生成量Ｓ_a を増減させてもよい。
【００９６】
このように、上記第１，第２の実施の形態では準備時間Ｔ_s をＥＮＡＢＬＥ信号出力の判断基準としたのに対して、本実施の形態では水素生成量の推定値をＥＮＡＢＬＥ信号出力の判断基準としているため、より精度の高いＥＮＡＢＬＥ信号出力の判断が可能となり、その結果として、ロボット１への電力供給が不足する可能性を著しく低減させることができる。
【００９７】
尚、図１０を参照して、温度センサ４１の不良等により、オブザーバー４０が正常に機能しなくなると、発電管理手段７から改質器９と可変弁１０に対して水素生成量の増加指示がなされ、実際には改質器９による水素生成量が前記判定基準水素生成量Ｓ_a まで増加している場合であっても、オブザーバー３０により推定される改質器９の水素生成量が前記判定基準水素生成量Ｓ_a 以上とならない場合がある。この場合、作動制御手段２に対してＥＮＡＢＬＥ信号が送信されないため、ロボット１が作動不能となる。
【００９８】
そこで、このような作動不能が生じることを防止するため、以下の処理を行うようにしてもよい。即ち、シーケンスマネージャ２４は、前記増加指示をする際に、前記第１，第２の実施の形態と同様に前記準備時間Ｔ_s を算出する。そして、前記増加指示を行ってから準備時間Ｔ_s が経過したときは、改質器９による水素生成量が前記判定基準水素生成量Ｓ_a 以上となっていると想定される。
【００９９】
そのため、シーケンスマネージャ２４は、改質器９及び可変弁１０に対して前記増加指示を行ってから前記準備時間Ｔ_s が経過したときには、燃料生成量把握手段３０により推定される改質器９の水素生成量が前記判定基準水素生成量Ｓ_a に達していなくても、作動制御手段２に対してＥＮＡＢＬＥ信号を送信する。これにより、上述したロボット１の作動不能が生じることを防止することができる。
【０１００】
また、前記第１〜第３の実施の形態では、本発明の蓄電手段として、電気二重層コンデンサを用いたが、電気二重層以外のコンデンサや、リチウム−イオンバッテリー等の二次電池を用いてもよい。
【０１０１】
また、前記第１〜第３の実施の形態では、電気二重層コンデンサ４からロボット１に作動用電力を供給するようにしたが、ロボット１の消費電力が小さく、燃料電池５からの供給電力でロボット１を作動させることができる場合には、電気二重層コンデンサ４及び定電流充電回路３を設けずに、燃料電池５から直接ロボット１に作動用電力を供給するようにしてもよい。
【０１０２】
また、前記第１〜第３の実施の形態では、改質器としてメタノールを原料とするものを用いたが、他の方式の改質器を用いてもよい。
【図面の簡単な説明】
【図１】第１の実施の形態における制御ブロック図。
【図２】燃料電池の作動説明図。
【図３】目標圧設定手段の構成図。
【図４】リザーブタンク圧力の推移説明図。
【図５】リザーブタンク圧力の推移説明図。
【図６】シーケンスマネージャの動作フローチャート。
【図７】発電管理手段のタイムチャート。
【図８】発電管理手段のタイムチャート。
【図９】第２の実施の形態における制御ブロック図。
【図１０】オブザーバーの構成図。
【図１１】第３の実施の形態における制御ブロック図。
【符号の説明】
１…２足歩行ロボット、２…作動制御手段、３…定電流充電回路、４…電気二重層コンデンサ、５…燃料電池、６…水素供給手段、７…発電管理手段、８…原料タンク、９…改質器、１０…可変弁、１１…レギュレータ、１２…リザーブタンク、２３…必要水素生成量算出手段、２４…シーケンスマネージャ、２５…改質器生成量指示手段、２６…目標圧設定手段、２９…水素消費量換算手段、４０…オブザーバー[0001]
[Field of the Invention]
The present invention relates to a power generation amount control of a fuel cell in a legged mobile robot using a fuel cell as a power source.
[0002]
[Prior art]
Conventionally, as a power source for a legged mobile robot, an external power source connected via an electric wire or a secondary battery such as a lithium-ion battery has been used. However, when an external power source is used, since it is necessary to connect via an electric wire, there is a fatal defect that the movement range of the robot is limited.
[0003]
In addition, when a secondary battery such as a lithium-ion battery is mounted on the robot, the movement range of the robot is not limited, but the energy capacity of the secondary battery that can be mounted is limited in terms of weight limitation. Therefore, there is a disadvantage that the continuous walking time of the robot is limited to about 30 minutes. Further, the secondary battery has a disadvantage that the charging time is long.
[0004]
It is also conceivable to install an engine generator on the robot. In this case, however, there are problems such as harmful exhaust gas emitted from the engine and engine noise, which is inconvenient for robots collaborating with humans. Is appropriate.
[0005]
Therefore, it is conceivable to install a fuel cell having a larger energy capacity with respect to weight than a lithium-ion battery and generating no harmful gas or noise as a power source in a robot. However, the output power of the fuel cell changes according to the supply amount of hydrogen as a fuel.
[0006]
Hydrogen is generated from a fuel such as methanol by a reformer by a chemical reaction. Increasing the amount of hydrogen generated in the reformer increases the heater temperature of the reformer or the amount of air supplied to the reformer. And by increasing the supply amount of fossil fuel and increasing the pressure, the chemical reaction is promoted. For this reason, there is a time delay from when the instruction to increase the amount of hydrogen generation is given to the reformer until the amount of hydrogen supplied from the reformer actually increases.
[0007]
Therefore, when the load on the drive system such as a motor suddenly increases, such as when a legged robot starts to walk, hydrogen is supplied to the reformer in order to obtain electric power corresponding to the load on the drive system from the fuel cell. Even if a measure for increasing the supply amount is performed, the supply amount of hydrogen to the fuel cell does not increase immediately due to the time delay described above, and there may be a case where the power supplied from the fuel cell to the drive system is insufficient.
[0008]
In order to prevent the delay time from occurring, it is conceivable to provide a reserve tank in the fuel supply path from the reformer to the fuel cell, but the legged movement has a large difference in power consumption between stationary and walking. In the robot, a large reserve tank that can secure the fuel supply to the fuel cell in response to a sudden load change at the start of walking is required. As a result, the installation space for the reserve tank is increased and the weight is increased.
[0009]
[Problems to be solved by the invention]
The present invention provides a legged mobile robot that solves the above inconveniences and prevents a shortage of power supplied from the fuel cell when the load on the drive system increases rapidly without providing a large reserve tank. The purpose is to do.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a legged mobile robot having an action plan function that operates according to a predetermined action plan, a fuel cell that supplies electric power for operating the legged robot, and a leg according to the action plan. Control means for controlling the operation of the mobile robot, and power generation management means for monitoring the state of the fuel cell and the content of the action plan and adjusting the power generation amount of the fuel cell in accordance with the action plan. It is characterized by that.
[0011]
The operation of the legged mobile robot of the present invention is controlled by the operation control means according to the action plan. The power generation management unit monitors the state of the fuel cell and the content of the action plan, and adjusts the power generation amount of the fuel cell according to the action plan. Therefore, when the action plan is executed, the power generation amount of the fuel cell is controlled so that the output power from the fuel cell is not insufficient, and the fuel cell having a large energy capacity per weight is used as the power source of the legged mobile robot. be able to.
[0012]
Also provided is a raw material holding means for holding a raw material for generating fuel for the fuel cell, and a reformer for generating fuel for the fuel cell from the raw material supplied from the raw material holding means and supplying the fuel cell to the fuel cell. The power generation management means instructs the reformer to increase or decrease the amount of fuel generated according to the fuel consumption of the fuel cell, and the action plan is executed based on the contents of the action plan. When analyzing in advance and recognizing in the action plan that a large load operation that requires the power supplied from the fuel cell to exceed a predetermined level is executed, before the large load operation is executed, A preceding process for instructing the reformer to increase the fuel generation amount is performed.
[0013]
According to the present invention, when the power generation management means recognizes that the heavy load operation is executed by analyzing the action plan, the power generation management means instructs the reformer to increase the fuel generation amount in advance. I do. Accordingly, the amount of fuel supplied from the reformer to the fuel cell can be increased before the large load operation is executed, and the output power of the fuel cell is insufficient when the large load operation is executed. Can be prevented. In this case, a large reserve tank for holding fuel in advance in preparation for the execution of the heavy load operation is unnecessary.
[0014]
In addition, a reserve tank that supplies the fuel cell while holding the fuel output from the reformer, and the power generation management means, so that the pressure in the reserve tank does not exceed a predetermined upper limit pressure, The preceding process is performed.
[0015]
When the preceding process is performed, the pressure in the reserve tank gradually increases due to the fuel output from the reformer. However, the pressure allowable in the reserve tank has an upper limit (upper limit pressure), and if the upper limit pressure is exceeded, the reserve tank may be damaged. Therefore, by performing the preceding process so that the pressure in the reserve tank does not exceed such an upper limit pressure, it is possible to prevent the reserve tank from being damaged. In the preceding process, since the pressure in the reserve tank does not exceed the upper limit pressure, a reserve tank having a minimum necessary size corresponding to the upper limit pressure may be prepared. For this reason, the reserve tank has a small margin, and the reserve tank can be reduced in size and weight.
[0016]
In addition, the power generation management means, as the preceding process, supplies fuel to the reformer so that the amount of fuel supplied from the reformer to the fuel cell becomes equal to or greater than the required supply amount according to the heavy load operation. The preparation time, which is an estimated time from when the increase in the production amount is instructed until the fuel is actually supplied at the target production amount set according to the required supply amount, is at least the reaction delay of the reformer. It is determined by characteristics, and when the preparation time has elapsed after the increase instruction, the operation control means is instructed to start execution of the heavy load operation.
[0017]
According to the present invention, when the preparation time has elapsed, that is, when it is assumed that the amount of fuel generated by the reformer has reached the target generation amount, the power generation control unit is provided with the operation control unit. The start of execution of the heavy load operation is instructed. Therefore, it is possible to prevent the output power of the fuel cell from becoming insufficient when the large load operation is executed.
[0018]
In addition, a fuel supply amount grasping means for grasping the amount of fuel produced by the reformer is provided, and the power generation management means at least generates the fuel so that fuel is supplied at the necessary supply amount in the preceding process. The degree of increase instruction to the reformer is determined in accordance with the fuel generation amount grasped by the amount grasping means.
[0019]
According to the present invention, the power generation management unit corrects the degree of increase instruction to the reformer according to the fuel generation amount grasped by the fuel production amount grasping unit. By the time elapses, the amount of fuel produced by the reformer can be reliably increased to the target production amount.
[0020]
In addition, a fuel generation amount grasping means for grasping the fuel generation amount by the reformer is provided, and the power generation management means is configured such that the fuel supply amount from the reformer to the fuel cell is the large load operation as the preceding process. Instructing the reformer to increase the amount of fuel generated so that the required supply amount is greater than or equal to the required supply amount. After the increase instruction, the fuel generation amount grasped by the fuel production amount grasping means is the required fuel amount. When the amount exceeds a target generation amount set according to the supply amount, the operation control means is instructed to start executing the heavy load operation.
[0021]
According to the present invention, the power generation management means provides the operation control means when the fuel generation amount grasped by the fuel production amount grasping means becomes equal to or more than the target production amount in the preceding process. The start of execution of the heavy load operation is instructed. Therefore, it is possible to prevent the large load operation from being started in a state where the amount of fuel supplied from the reformer to the fuel cell is insufficient.
[0022]
Further, the power generation management means, when performing the preceding process, supplies the reformer with a fuel supply amount from the reformer to the fuel cell so as to be equal to or greater than a necessary supply amount according to the large load drive. A preparation time, which is an estimated time from when the fuel generation amount is instructed to increase to the actual generation of fuel at the target generation amount, is calculated. After the increase instruction, the fuel generation amount grasping means When the grasped fuel generation amount becomes equal to or greater than the target generation amount, or when the preparation time has elapsed, the operation control means is instructed to start execution of the heavy load operation.
[0023]
When a malfunction occurs in the operation of the fuel generation amount grasping means, the fuel generation amount grasped by the fuel generation amount grasping means even if the fuel generation amount by the reformer actually increases due to the increase instruction. May not increase and the target generation amount may not be reached.
[0024]
In this case, when the preparation time elapses after the increase instruction is given, it is assumed that the amount of fuel produced by the reformer has increased to the target production amount or more. Therefore, when the preparation time elapses after the increase instruction, the power generation amount management unit has reached the target generation amount of the reformer fuel generation amount grasped by the fuel production amount grasping unit. Even if not, the operation control means is instructed to start execution of the heavy load operation. Thereby, it is possible to prevent the legged mobile robot from becoming inoperable due to a defect in the fuel generation amount grasping means.
[0025]
The fuel generation amount grasping means uses the power generation amount of the fuel cell, the temperature in the reformer, and the supply pressure of fuel from the reformer to generate the fuel generation amount by the reformer. It is characterized by grasping.
[0026]
From the reformer to the fuel cell, not only fuel but also other gas such as water vapor generated with the generation of fuel is supplied. For this reason, it is difficult to directly detect the fuel supply amount. Therefore, in the present invention, the fuel generation amount grasping means uses the power generation amount of the fuel cell, the temperature in the reformer, and the supply pressure of the fuel from the reformer, The amount of fuel produced by the vessel is estimated indirectly. Thereby, the amount of fuel produced by the reformer can be easily grasped.
[0027]
The legged movement according to any one of claims 1 to 8, further comprising a power storage unit that is charged by output power of the fuel cell, and obtains operating power from the power storage unit. robot.
[0028]
In general, since a fuel cell has a small instantaneous maximum output power, there is a case where a sufficient power supply according to the large load operation cannot be obtained. Therefore, in the present invention, operating power is supplied to the legged robot from the power storage means charged with the output power of the fuel cell. In this case, since the instantaneous maximum output power of the power storage means can be made larger than the instantaneous maximum output power of the fuel cell, it is possible to supply power according to the large load operation.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a control block diagram according to the first embodiment of the present invention, FIG. 2 is an operation explanatory diagram of a fuel cell, FIG. 3 is a configuration diagram of target pressure setting means, and FIGS. 4 and 5 are transition descriptions of reserve tank pressure. FIG. 6, FIG. 6 is an operation flowchart of the sequence manager, FIG. 7 and FIG. 8 are time charts of the power generation management means, FIG. 9 is a control block diagram according to the second embodiment of the present invention, FIG. These are the control block diagrams in the 3rd Embodiment of this invention.
[0030]
First, a first embodiment of the present invention will be described with reference to FIGS. Referring to FIG. 1, a legged mobile robot 1 according to the present embodiment is a biped walking robot, and includes an operation control means 2 for controlling the operation of a driving means such as a motor, a constant current charging circuit 3 and a robot 1. A fuel cell 5 that supplies electric power for operation via an electric double layer capacitor 4 (corresponding to a power storage unit of the present invention), a hydrogen supply unit 6 that supplies hydrogen as fuel to the fuel cell 5, and a hydrogen supply unit 6 Power generation management means 7 for controlling the power generation amount of the fuel cell 5 by adjusting the hydrogen supply amount from the fuel cell 5 to the fuel cell 5.
[0031]
Hydrogen is supplied as a fuel to the negative electrode side of the fuel cell 5 and air is supplied as an oxidant to the positive electrode side to generate power. That is, in each of the positive and negative electrodes of the fuel cell 5,
Negative electrode: H ₂ → 2H ⁺ + 2e ^- (A)
Positive electrode: 1 / 2O ₂ + 2H ⁺ + 2e ^- → H ₂ O (B)
A chemical reaction occurs, and electric power is supplied from the fuel cell 5 to the constant current charging circuit 3, whereby the electric double layer capacitor 4 is charged.
[0032]
Thus, by supplying the operating power of the robot 1 from the electric double layer capacitor 4, the disadvantage of the fuel cell 5 that the instantaneous maximum output power is small is compensated, and the power supply according to the power consumption of the robot 1 can be obtained. So that.
[0033]
A hydrogen supply means 6 is a raw material tank 8 for holding methanol, which is a raw material of hydrogen (corresponding to the raw material holding means of the present invention), and methanol supplied from the raw material tank 8 is decomposed into hydrogen and carbon dioxide by a catalyst, A reformer 9 that generates hydrogen as fuel of the battery 5, a variable valve 10 that adjusts the amount of methanol supplied from the raw material tank 8 to the reformer 9, and supply of hydrogen from the reformer 9 to the fuel cell 5 It comprises a regulator 11 that reduces the pressure to a constant value (for example, 0.3 atm), and a reserve tank 12 that ensures a sufficient supply amount of hydrogen from the reformer 9 to the fuel cell 5.
[0034]
Here, from the above formula (A), the output power of the fuel cell 5 increases or decreases in accordance with the amount of hydrogen reaction (hydrogen consumption) in the fuel cell 5. Therefore, it is necessary to supply an appropriate amount of hydrogen to the fuel cell 5 in accordance with an increase or decrease in the amount of power supplied from the electric double layer capacitor 4 to the robot 1 (the amount of discharge of the electric double layer capacitor 4).
[0035]
When the amount of hydrogen consumed in the fuel cell 5 increases and exceeds the amount of hydrogen supplied from the reformer 9, the amount of hydrogen in the reserve tank 12 decreases, so the pressure in the reserve tank 12 decreases. . Conversely, when the amount of hydrogen consumed in the fuel cell is smaller than the amount of hydrogen supplied from the reformer 9, the amount of hydrogen in the reserve tank 12 increases, and the pressure in the reserve tank 12 increases. Therefore, by detecting the pressure in the reserve tank 12, it is possible to recognize whether the amount of hydrogen supplied to the fuel cell 5 is excessive or insufficient.
[0036]
The power generation management unit 7 needs to analyze the action plan received from the operation control unit 2 and calculate the hydrogen generation amount of the reformer 9 necessary for execution of the action plan (hereinafter referred to as the necessary hydrogen generation amount). The hydrogen generation amount calculation means 23, the required hydrogen generation amount, the action plan, and the detected pressure of the reserve tank 12 are input, and ENABLE (operation permission) / INHIBIT (operation inhibition) is output to the operation control means 2. In addition, the sequence manager 24 that determines the timing for changing the hydrogen generation amount of the reformer 9, and the reformer that instructs the reformer 9 to change the hydrogen generation amount according to an instruction from the sequence manager 24. According to the generation amount instruction means 25, the indicated value of the hydrogen generation amount by the reformer generation amount instruction means 25, and the hydrogen consumption amount of the fuel cell 5 calculated by the hydrogen consumption amount conversion means 29, the reserve And a target pressure setting means 26 for setting a target pressure of the tank 12.
[0037]
The power generation management means 7 performs control to keep the pressure in the reserve tank 12 at the target pressure (for example, 1 atmosphere) set by the target pressure setting means 26. As described later, this target pressure is not always constant. The power generation management means 7 performs feedback control that adjusts the amount of hydrogen generated in the reformer 9 so that the pressure in the reserve tank 12 detected by a pressure sensor (not shown) matches the target pressure, The fuel supply amount to the fuel cell 5 is prevented from being insufficient. Specifically, the power generation management means 7 subtracts the detected pressure in the reserve tank 12 from the target pressure at the addition point 20, and sets the hydrogen generation amount instruction value in the arithmetic unit 21 so that the subtraction result becomes zero. decide. Then, the power generation management means 7 instructs the reformer 9 to adjust the supply amount of air and the reforming temperature in accordance with the determined value of the hydrogen generation amount, and also provides the variable valve 10 with methanol. Instructs to adjust the supply amount.
[0038]
The operation control means 2 is for realizing the action planning function of the robot 1. That is, when the robot 1 performs a series of operations, for example, walking at a fixed distance, the operation control means 2 creates an action plan that defines an operation procedure of a drive system such as a motor in accordance with the operation. The operation of the drive system of the robot 1 is controlled according to the plan.
[0039]
By the way, in a biped robot, the power consumption during walking may increase to more than twice the power consumption during stoppage. In such a case, the fuel cell 5 needs to rapidly increase the amount of power generation when the robot 1 starts walking. However, since the reformer 9 generates hydrogen by chemically reacting methanol and oxygen as described above, the power generation management means 7 performs the above-described feedback control when the robot 1 starts walking. Even if an instruction to increase the amount of hydrogen produced by is given, there will be a time delay before hydrogen is produced in an amount corresponding to the electric power actually required for walking.
[0040]
The graphs (a) and (b) shown in FIG. 2 show how such a time delay occurs, and the vertical axis indicates the amount of hydrogen produced by the reformer 9 or the amount of hydrogen produced for the reformer 9. The indicated value, the horizontal axis is time. In FIG. ₀ Is the amount of hydrogen produced by the reformer 9 required when the robot 1 is stopped (= indicated value of the amount of hydrogen produced for the reformer 9 and the variable valve 10), A ₁ Is the amount of hydrogen produced by the reformer 9 (= indicated value of the amount of hydrogen produced for the reformer 9 and the variable valve 10) required when the robot 1 is in a walking state (corresponding to the heavy load operation of the present invention). t ₁ Is the walking start time, t ₂ Is the walking end time.
[0041]
With reference to the graph (a), the power generation management means 7 starts walking (time t) of the robot 1 by the feedback control described above. ₁ ), The indicated value of the hydrogen generation amount is set to A for the reformer 9 and the variable valve 10. ₀ To A ₁ Even if it is increased, the hydrogen production amount by the reformer 9 is actually A. ₁ Until a time delay T is reached as shown in the graph (b). _d Produce. Therefore, in this case, when the robot 1 starts walking, the power for operation is insufficient, and the action plan by the operation control means 2 may not be executed normally.
[0042]
Therefore, referring to FIG. 1, the power generation management means 7 performs a preceding process for instructing the reformer 9 and the variable valve 10 to increase the hydrogen generation amount before starting walking. Reference numeral 22 denotes a feedforward unit corresponding to the preceding process, and the power generation management unit 7 analyzes the content of the action plan created by the operation control unit 2, and the power supplied from the fuel cell 5 is predetermined in the action plan. Monitor whether or not a heavy load operation that exceeds the level occurs.
[0043]
When the power generation management unit 7 recognizes that the large load operation occurs, the power generation management unit 7 transmits an INHIBIT signal to the operation control unit 2 to prohibit the operation control unit 2 from executing the large load operation. Next, the required hydrogen generation amount calculating means 23 is a required hydrogen generation amount S that is a hydrogen generation amount corresponding to the electric power required for the heavy load operation. _n (Equivalent to the required supply amount of the present invention, A in FIG. ₁ Is S _n Is calculated from a data table, a relational expression, or the like obtained in advance by experiments.
[0044]
The sequence manager 24 provided in the power generation management means 7 _S Is calculated and compared with the current time, and the subsequent operation sequence is instructed to the operation control means 2 and the reformer generation amount instruction means 25. In response to this instruction, the reformer generation amount instruction means 25 determines the hydrogen generation amount by the reformer 9 as A. ₁ An instruction value for calculating The indicated value is added to the output of the arithmetic unit 21 at the addition point 27, and the amount of hydrogen generated in the reformer 9 is A with respect to the reformer 9 and the variable valve 10. ₁ An increase instruction is given. At this time, the reformer 9 and the variable valve are switched by switching the switch 28, interrupting the above-described feedback control by the addition point 20 and the calculation unit 21, and performing only the preceding process by the feedforward unit 22. 10 may be prevented from being limited by the feedback control.
[0045]
Alternatively, the target pressure setting means 26 outputs the estimated value of the pressure transition when hydrogen is generated using only the output of the reformer generation amount instruction means 25 as the direct hydrogen generation amount instruction value, thereby equivalently adding them together. By canceling the feedback control operation by the point 20 and the computing unit 21 (that is, by making the output of the computing unit 21 almost zero), the increase in the amount of hydrogen generated in the reformer 9 is limited by the feedback control. This may be prevented.
[0046]
FIG. 3 is an explanatory diagram of the target pressure setting means 26. An instruction value from the reformer generation amount instruction means 25 and a hydrogen consumption amount calculated by a hydrogen consumption conversion means 29 described later are input and reserved. The sum of the pressure fluctuation estimated by the tank model 30 and a predetermined reserve tank pressure set value around 1 atm is output as a reserve tank pressure target value. The reserve tank model 30 may be the same as that used in the observer of FIG. 10 described later. Alternatively, the addition output from the reformer generation amount instruction means 25 to the addition point 27 may be equivalently converted to be equivalent to the pressure fluctuation.
[0047]
The operation of the target pressure setting unit 26 will be described in detail with reference to FIG. 3. The target pressure setting unit 26 first generates reformer hydrogen from the time-series generation amount instruction received from the reformer generation amount instruction unit 25. The amount estimation calculator 31 calculates a time-series hydrogen generation amount. Next, the actual time value of the hydrogen consumption by the fuel cell 5 calculated by the hydrogen consumption conversion means 29 is subtracted from the calculated hydrogen production amount at the addition point 32, and the reserve tank model 30 is used from the subtraction result. The amount of pressure fluctuation in the reserve tank 12 is estimated.
[0048]
As a result, the pressure fluctuation of the reserve tank pressure caused by the feedforward control by the reformer generation amount instruction means 25 can be added to the reserve tank pressure target value (indicated value). By performing the feedback control based on the above, it is possible to prevent the above-described feedforward control from being affected by the feedback control.
[0049]
The power generation management means 7 gives a preparation time T after instructing the reformer 9 and the variable valve 10 to increase the hydrogen generation amount. _s When elapses, a walking permission (ENABLE) signal is transmitted to the operation control means 2 (corresponding to an instruction to start execution of the heavy load operation of the present invention). Here, referring to the graph (c) in FIG. 2, the region {circle around (1)} is the surplus hydrogen generation amount, and the region {circle around (2)} having the same area consumes this surplus. That is, preparation time T _S Later, walking of the robot 1 can be started. Further, h (t) in the graph (c) is the actual amount of hydrogen produced by the reformer 9, and g (t) is the actual amount of hydrogen consumed by the fuel cell 5. Then, by instructing the reformer 9 and the variable valve 10 to increase the hydrogen generation amount before starting the walking of the robot 1 in this way, the change in the pressure of the reserve tank 12 is shown in the graph (d) of FIG. Smaller as shown. Therefore, the reserve tank 12 can be reduced in size.
[0050]
However, the actual delay time T in the graph (b) of FIG. _d Therefore, in this embodiment, the reformer 9 is assumed to be a first-order lag element of the time constant τ (τ is determined in advance by experiment), and the preparation time T _s calculate. Hereinafter, referring to the graph (c) in FIG. _s The calculation method of will be described. For convenience of explanation, the hydrogen generation amount A when the robot 1 is in a stopped state is shown. ₀ Is set to 0, and the hydrogen production is A ₁ The time t when the increase instruction is given ₀ Is set to 0. Further, it is assumed that the rise and fall of the hydrogen generation amount by the reformer 9 are the same.
[0051]
The graph (c) shows the functions g (t) and h (t) shown below superimposed.
[0052]
[Expression 1]

[0053]
[Expression 2]

[0054]
g (t) is time t ₁ To time t ₂ Shows the transition of the ideal hydrogen generation amount when walking up to (the heavy load operation), h (t) is the time t ₁ Predicted delay time T _s Previous time t ₀ To t _w (T _w -T ₀ = T ₂ -T ₁ = Amount of hydrogen supply until A) ₁ When the instruction is given, the transition of the hydrogen generation amount by the reformer 9 assumed to be a first order lag element is shown. The areas of (1) and (2) in the graph (c) are respectively
[0055]
[Equation 3]

[0056]
[Expression 4]

[0057]
It becomes. From the balance between the amount of hydrogen produced by the reformer 9 and the amount of hydrogen consumed by the fuel cell 5, (1) = (2) and t ₁ Ask for
[0058]
[Equation 5]

[0059]
It becomes. Where t _w >> Since τ can be assumed,
[0060]
[Formula 6]
t ₁ ≒ τ (6)
It becomes.
[0061]
Therefore, the power generation management means 7 sets the time constant τ to the preparation time T _s And That is, referring to the graph (e) in FIG. ₀ Preparation time T after giving an increase instruction at _s The time t when ₁ Then, the ENABLE signal is transmitted to the operation control means 2. At this time, the hydrogen production amount of the reformer 9 assumed to be a first-order lag element changes as indicated by the dotted line, and the time t ₁ The amount of hydrogen produced at ₀ + (A ₁ -A ₀ ) × 63.2% (corresponding to the target production amount of the present invention). As a result, the region {circle around (1)} in the graph (c) of FIG. 2 becomes the surplus hydrogen generation amount, and the region {circle around (2)} of the same area uses this surplus, and there is no problem in walking of the robot 1. .
[0062]
And the power generation management means 7 is the walking end time t ₂ Preparation time T _s T which is the previous time _w The indicated value of the hydrogen production amount is A ₁ To A ₀ To lower. Thereby, with reference to the graph (d) of FIG. 2, it can prevent that the pressure of the reserve tank 12 rises too much after a walk stop.
[0063]
When the delay time of the reformer 9 is large, as shown in the graph (f) of FIG. ₁ A beyond ₂ Until the instruction to increase the hydrogen generation amount is given, the hydrogen generation amount by the reformer 9 becomes the target hydrogen generation amount S. _a You may make it shorten the time required to increase to.
[0064]
Next, referring to FIG. 4 and FIG. 5, the preparation time T is generated by the power generation management means 7 described above. _s The effect of reducing the pressure change in the reserve tank 12 when controlling the amount of hydrogen generated by the reformer 9 will be described. Graphs (a), (b), and (c) of FIG. 4 show changes in pressure in the reserve tank 12 when the robot 1 is walked by the conventional method, and graphs (d), (e), and (f) Preparation time T _s Is the time constant τ, and the pressure change in the reserve tank 12 when the robot 1 walks, graphs (g), (h), (i) in FIG. _S The pressure change in the reserve tank 12 when the robot 1 walks with the time constant τ being shorter than the time constant τ will be described.
[0065]
In the conventional method, referring to FIG. 4, time t at which the amount of hydrogen generation in graph (a) is increased. ₀ And the time t when the robot 1 starts walking in the graph (b). ₁ Is the same. As a result, for a while after the start of walking, the hydrogen consumption of the fuel cell 5 shown in the graph (b) becomes larger than the actual value of the hydrogen generation amount by the reformer 9 shown in the graph (a). As shown in (c), the pressure in the reserve tank 12 greatly decreases and falls below the minimum operating pressure that is the minimum pressure of the reserve tank 12 necessary for the operation of the robot 1. In this case, the amount of hydrogen supplied to the fuel cell 5 is reduced, causing a power generation shortage.
[0066]
In addition, when walking is stopped, the actual value of the hydrogen generation amount shown in the graph (a) exceeds the hydrogen consumption amount shown in the graph (b), so that the pressure in the reserve tank 12 is increased as shown in the graph (c). May exceed the limit maximum pressure determined from the specifications of the reserve tank 12, which is not preferable. And in order to avoid these problems, when the capacity | capacitance of the reserve tank 12 is increased, the disadvantage that the reserve tank 12 enlarges and a weight increase arises.
[0067]
Therefore, in the example shown in FIG. 4, the time t of the graph (d) ₀ After instructing to increase the amount of hydrogen produced in step (b), as shown in the graph (e), the preparation time T _S The time t when ₁ The robot 1 starts walking. Preparation time T _S As described above, is set to the time constant τ when the reformer 9 is regarded as the first-order lag element. By delaying the walking start timing of the robot 1 in this way, as shown in the graph (f), the pressure fluctuation of the reserve tank 12 can be reduced compared to the graph (c) of the conventional example described above. Therefore, the reserve tank 12 can be reduced in size and weight.
[0068]
In FIG. 5, the graph (h) shows the preparation time T shown in the graph (g). _S Is set to a time shorter than the time constant τ described above. As a result, as shown in the graph (i), the pressure change in the reserve tank 12 can be made smaller than in the case of the first pressure fluctuation reducing method shown in the graph (f) of FIG. Therefore, the reserve tank 12 can be made smaller and lighter. In this case, preparation time T _S Is
T _S = Time constant (τ) x Constant (1 or less)
This is applied to each of when walking starts and when walking stops. Preparation time T _S Can be set as precisely as necessary.
T _S = F (current pressure, target generation change, target pressure set value, pressure upper limit value, pressure lower limit value, time constant)
Therefore, the pressure in the reserve tank 12 may be calculated so as not to exceed the pressure upper limit value (corresponding to the predetermined upper limit pressure of the present invention). Here, the current pressure is the current pressure of the reserve tank 12, the target pressure set value is the target value of the pressure of the reserve tank 12, and is an input variable together with the target generation change amount. The other parameters are parameters, and the time constant is a time constant when the reformer 9 described in FIG. 2 is regarded as a first-order lag. For example, when the current pressure is high, the amount of hydrogen in the reserve tank 12 is sufficient, so the preparation time T _S Can be set to a shorter time. Preparation time T _S In addition to calculating from the relational expression in this way, it may be calculated from a data table or the like obtained in advance through experiments.
[0069]
Subsequently, with respect to the specific operation of the power generation management means 7 (see FIG. 1) in the first embodiment of the present invention, with reference to the overall configuration diagram shown in FIG. This will be described with reference to the flowchart shown in FIG. 6 and the time charts shown in FIGS. 7 and 8, the graph (a) is the transition of the operation state of the sequence manager 24, the graph (b) is the content of the action plan (here, the walking plan) instructed from the operation control means 2, and the graph (c) ) Is the transition of the hydrogen consumption of the fuel cell 5 (corresponding to the power consumption of the robot 1), the graph (d) is the transition of the hydrogen generation amount of the reformer 9, and the graph (e) is the control signal for the operation control means 2. The change in the output of (ENABLE / INHIBIT) is shown respectively.
[0070]
With reference to the flowchart of FIG. 6, the sequence manager 24 repeatedly executes the routine of STEP1 to STEP6. In the routine of STEP 1 to STEP 6, the operation state of the sequence manager is “a waiting plan change waiting state” which is a state waiting for a walking plan instruction from the operation control means 2, and a walking plan instruction from the operation control means 2. , A “reforming generation instruction waiting state”, which is a state of waiting for a timing for instructing the reformer 9 to change the hydrogen generation amount via the reformer generation amount instruction means 25, and the reformer 9 is instructed to change the hydrogen production amount, and then the preparation time T _S Is one of three types of states, ie, “reformation generation preceding state”, which is a state of waiting for the elapse of time.
[0071]
When in the “Walking Plan Change Waiting State”, the sequence manager 24 branches from STEP2 to STEP10. When there is a walking plan change request from the operation control means 2 in STEP10, the sequence manager 24 proceeds to STEP11, and the operation control means. The content of the walking plan (instructions such as walking start, walking stop, etc.) is received from 2, and the process shifts to the “waiting for modification generation instruction” state. On the other hand, when there is no request to change the walking plan from the operation control means 2 in STEP 10, the “walking plan change waiting state” is maintained.
[0072]
When in the “reforming generation instruction waiting state”, the sequence manager 24 branches from STEP 3 to STEP 20, and in STEP 20 the preparation time T _S Is calculated. Then, in STEP 21, the current time t is the instruction time t for starting the walking plan. _P T _S When time has passed (t ≧ t _P -T _S ), The process proceeds to STEP 22 where the reformer generation amount instruction means 25 calculates the hydrogen generation amount for the reformer 9 and instructs the reformer 9. In subsequent STEP 23, the sequence manager 24 outputs an INHIBIT signal to the operation control unit 2 to prohibit the operation change of the operation control unit 2, and shifts to the “reformation generation preceding state”.
[0073]
When in the “reformation generation preceding state”, the sequence manager 24 moves to the “reformation generation preceding state” in STEP 4 and then prepares time T. _S When elapses, the process proceeds to STEP 5 to transmit an ENABLE signal to the operation control means 2. By receiving this ENABLE signal, the operation control means 2 executes the requested walking plan. Then, the sequence manager 24 shifts to a “walking plan change waiting state”.
[0074]
It should be noted that the ENABLE signal is a signal having a meaning of permitting the change control of the operation of the robot 1 by the operation control means 2, and does not have a meaning of permitting the walking itself. That is, when the ENABLE signal is output from the sequence manager 24 to the operation control means 2, the change of the operation of the robot 1 is permitted, and the operation control means 2 performs control to stop the walking robot 1, for example. Can do. On the other hand, when the ENABLE signal is not output, the operation change of the robot 1 is prohibited. For example, if the robot 1 is walking, the robot 1 continues walking.
[0075]
A specific example of operating the legged mobile robot 1 will be described with reference to the time charts of FIGS. 7 and 8 according to the flowchart of FIG. 6 described above.
[0076]
FIG. 7 shows an example in which there is a waiting time from when the sequence manager 24 receives the walking plan from the operation control means 2 until when the legged mobile robot 1 actually starts walking. Referring to FIG. 7, when the sequence manager 24 is in the “waiting for walking plan change state” (ST11 in (a)), the sequence manager 24 sends the time t _P When the instruction of the walking plan to start walking at 1 ((1) of (b)) is received ((2) of (c)), the walking start time t _P 1 preparation time T _S T which is the previous time _C Until 1 (T _w 1) “Reforming generation instruction waiting state” (ST12 of (a)).
[0077]
And time t _C 1, the sequence manager 24 increases the instruction value of the hydrogen generation amount for the reformer 9 via the reformer generation amount instruction means 25 ((3) in (d)). Thereby, as shown in (d), the amount of hydrogen produced in the reformer 9 increases. At the same time, the sequence manager 24 transmits an INHIBIT signal to the operation control means 2, prohibits the operation of the operation control means 2, and shifts to the "reformation generation preceding state" (ST13 of (a)).
[0078]
Walking start time t _P When it becomes 1, the sequence manager 24 outputs the ENABLE signal to the operation control means 2 to cancel the operation prohibition, thereby giving a walking start instruction ((5) of (d)). As a result, the legged mobile robot 1 starts walking under the control of the operation control means 2, and the sequence manager 24 shifts to the “waiting for walking plan change state” (ST21 in (a)).
[0079]
When the sequence manager 24 receives an operation plan instruction ((6) of (b)) to stop walking from the operation control means 2 ((7) of (c)), the sequence manager 24 _P 2 preparation time T _S 2 t, the previous time _C Up to 2 (T _w 1) “Reforming generation instruction waiting state” (ST22 of (a)).
[0080]
Time t _C 2, the sequence manager 24 decreases the instruction value of the hydrogen generation amount for the reformer 9 via the reformer generation amount instruction means 25 ((8) in (d)), The process proceeds to "state" (ST23 of (a)). Thereby, as shown in (d), the hydrogen production amount of the reformer 9 gradually decreases. The sequence manager 24 then determines the walking stop time t _P In step 2, the ENABLE signal is output to the operation control means 2 to give a walking stop instruction ((9) in (d)). By receiving this walking stop instruction, the legged mobile robot 1 stops walking under the control of the operation control means 2.
[0081]
Thus, the preparation time T from when the operation control means 2 instructs the sequence manager 24 to stop walking the legged mobile robot 1 until the robot 1 actually stops walking. _S By providing a delay time of 2, the amount of hydrogen supplied from the reformer 9 to the fuel cell 5 is excessive when walking is stopped, and the pressure in the reserve tank 12 is prevented from rising abnormally.
[0082]
Next, FIG. 8 shows an example in which walking of the legged mobile robot 1 is started at the same time or within a short time when the sequence manager 24 receives the walking plan from the operation control means 2. Referring to FIG. 8, when the sequence manager 24 is in a “walking plan change waiting state” (ST11 of (a)), an instruction of an operation plan for immediately starting walking from the operation stopping means 2 (▲ of (b)) 1)) ((2) in (c)), immediately, the indicated value of the hydrogen generation amount for the reformer 9 is increased via the reformer generation amount instruction means 25 ((3) in (d)). ▼). At the same time, the sequence manager 24 outputs an INHIBIT signal to the operation control means 2, prohibits the operation of the operation control means 2, and shifts to the "reformation generation preceding state" (ST13 of (a)). That is, the “reformation generation instruction waiting state” described in FIG. 7 (ST12 in FIG. 7A) does not occur.
[0083]
Thereby, as shown in (d), the hydrogen production amount of the reformer 9 gradually increases. The sequence manager 23 then prepares for the preparation time t _S Time t when 1 has passed _q In step 1, the ENABLE signal is output to the operation control means 2 to instruct walking start ((5) in (d)). That is, after the instruction to start walking of the legged mobile robot 1 from the operation control means 2, the preparation time T until the legged mobile robot 1 actually starts walking. _S By causing the delay time 1 to occur, the amount of hydrogen supplied from the reformer 9 to the fuel cell 5 is insufficient at the start of walking, thereby preventing a shortage of power generation by the fuel cell.
[0084]
When the sequence manager 24 receives from the operation control means 2 an action plan instruction ((6) in (b)) to stop walking ((7) in (c)), the modification production amount instruction means 25 immediately. Then, the instruction value of the hydrogen generation amount for the reformer 9 is decreased ((8) in (d)), and the process proceeds to the “reformation production preceding state” (ST23 in (a)). That is, as in the case of the start of walking, there is no “waiting for modification generation instruction” state.
[0085]
As a result, the hydrogen generation amount of the reformer 9 gradually decreases as shown in (d), and the sequence manager 24 prepares after the “reformation generation preceding state” (ST23 of (a)). Time T _S T, the time when 2 passed _q 2, the ENABLE signal is output to the operation control means 2 to instruct walking stop ((9) of (d)). As a result, as in the example shown in FIG. 7, the amount of hydrogen supplied from the reformer 9 to the fuel cell 5 becomes excessive when walking is stopped, and the pressure in the reserve tank 12 is prevented from rising abnormally.
[0086]
Next, a second embodiment of the present invention will be described with reference to FIGS. In addition, about the same component as FIG. 1, the same code | symbol is attached | subjected and description is abbreviate | omitted. In the first embodiment, the preparation time T _s The timing for transmitting the ENABLE signal (instruction to start walking) to the operation control means 2 is determined by _s Is calculated assuming that the reformer 9 is a first-order lag element, and it is considered that an error with respect to the delay time of the actual reformer 9 increases.
[0087]
Therefore, referring to FIG. 9, the power generation management means 7 in the second embodiment of the present invention is an observer 40 for grasping the hydrogen generation amount by the reformer 9 (corresponding to the fuel production amount grasping means of the present invention). ). Referring to FIG. 10, the observer 40 includes the hydrogen consumption of the fuel cell 5 calculated by the hydrogen consumption conversion means 29 from the power generation amount of the fuel cell 5, and the temperature inside the reformer 9 detected by the temperature sensor 41. The temperature and the pressure in the reserve tank 12 detected by the pressure sensor 42 are input, and the amount of hydrogen produced by the reformer 9 is estimated.
[0088]
That is, referring to FIG. 9, the hydrogen consumption conversion means 29 calculates the hydrogen consumption of the fuel cell 5 by dividing the power generation amount of the fuel cell 5 by the hydrogen consumption conversion rate. Referring to FIG. 10, the observer 40 receives as input the difference between the hydrogen consumption of the fuel cell 5 calculated by the hydrogen consumption conversion means 29 and the previous value of the estimated hydrogen generation amount of the observer 40 itself. In 44, the pressure in the reserve tank 12 corresponding to the volume of the reserve tank 12 is obtained, and in 45, the correction in consideration of the temperature in the reserve tank 12 is performed. Then, the difference between the corrected value and the detected pressure in the reserve tank 12 by the pressure sensor 42 is obtained at 46 and input to the transfer function H, and the output of the transfer function H is compared with the current hydrogen production amount by the reformer 9. presume.
[0089]
A plurality of types of transfer functions H may be used depending on whether importance is attached to responsiveness or estimation accuracy. The hydrogen consumption conversion rate may be regarded as 1 / (power generation efficiency of the fuel cell).
[0090]
Referring to FIG. 9, the power generation control means 7 takes the difference between the detected pressure of the reserve tank 12 at the addition point 41 and the pressure target value (near 1 atm) set by the target pressure setting means 26. The instruction value is calculated by the calculation unit 42 so that becomes zero. At the addition point 43, the instruction value from the calculation unit 42 and the instruction value for increasing the hydrogen generation amount by the reformer 9 from the reformer generation amount instruction unit 25 are added, and the hydrogen consumption conversion unit 29 is added. The hydrogen consumption of the fuel cell 5 calculated by the above is subtracted.
[0091]
At the addition point 44, the amount of hydrogen produced by the reformer 9 estimated by the observer 40 is subtracted from the indicated value from the addition point 43 so that the subtraction result becomes 0, that is, the addition point. The calculation unit 45 instructs the reformer 9 and the variable valve 10 of the hydrogen generation amount so that the instruction value from 43 matches the hydrogen generation amount by the reformer 9 estimated by the observer 40. A feedforward element 46 for improving the response speed may be added. Similarly to the switch 28 in FIG. 1, 47 interrupts the feedback control by the addition point 41 to prevent the instruction to increase the hydrogen generation amount for the reformer 9 and the variable valve 10 from being limited by the feedback control. It is a switch for.
[0092]
In this way, the observer 40 estimates the amount of hydrogen produced by the reformer 9, and obtains the difference between the estimated value, the amount of hydrogen produced, and the indicated value for the amount of hydrogen produced. When the increase degree of the actual hydrogen generation amount of the mass device 9 is small, control for further increasing the increase instruction value is performed. As a result, compared with the first embodiment of the present invention described above that does not use the observer 40, in the present embodiment shown in FIG. 9, the hydrogen generation amount instruction value that is the output of the reformer generation amount instruction means 25. On the other hand, since the local feedback is formed including the hydrogen generation amount observer 40, the control of the hydrogen generation amount with higher responsiveness and higher accuracy can be expected. Therefore, the preparation time T _S As a result, it is possible to reduce the possibility that the actual hydrogen generation amount approaches the predicted value with higher accuracy and the power supply to the robot 1 is insufficient as a result.
[0093]
Next, a third embodiment of the present invention will be described with reference to FIG. In the first and second embodiments described above, the preparation time T _s The timing for transmitting the ENABLE signal (instruction to start walking) to the operation control means 2 is determined based on the above, but in the third embodiment, the necessary hydrogen generation amount S is determined. _n Depending on the criterion hydrogen production amount S _a And S _a Is used as a reference to determine the timing for transmitting the ENABLE signal to the operation control means 2 (instruction to start walking).
[0094]
That is, the power generation management means 7 uses the required hydrogen generation amount calculation means 23 to generate the required hydrogen generation amount S. _n And calculate S _n Depending on the criterion hydrogen production amount S _a For example S _n Of 70%. And S _a The reformer 9 is instructed to increase the amount of hydrogen generation via the reformer generation amount instruction means 25 so that hydrogen is generated at. Note that the control processing ahead of the addition point 43 is the same as in the second embodiment.
[0095]
The sequence manager 24 then determines the criterion hydrogen production amount S. _a And the hydrogen generation amount S by the reformer 9 estimated by the observer 40 _p And S _p Is S _a When this is the case, the ENABLE signal is output to the operation control means 2. Thus, as in the first and second embodiments, the robot 1 starts walking (time t ₁ ), The amount of hydrogen generated by the reformer 9 can be increased to an amount necessary for walking, and it is possible to prevent the power supply amount from the fuel cell 5 from becoming insufficient at the start of walking. Further, according to the remaining pressure in the reserve tank 12, the determination reference hydrogen generation amount S _a May be increased or decreased.
[0096]
Thus, in the first and second embodiments, the preparation time T _s In this embodiment, the estimated value of the hydrogen generation amount is used as the determination criterion for the ENABLE signal output. Therefore, the ENABLE signal output can be determined with higher accuracy. As a result, the possibility that the power supply to the robot 1 is insufficient can be significantly reduced.
[0097]
Referring to FIG. 10, when the observer 40 does not function normally due to a failure of the temperature sensor 41 or the like, the power generation management means 7 instructs the reformer 9 and the variable valve 10 to increase the amount of hydrogen generation. In practice, the amount of hydrogen produced by the reformer 9 is the determination reference hydrogen production amount S. _a Even when the amount of hydrogen produced by the observer 30 is increased, the hydrogen production amount of the reformer 9 estimated by the observer 30 is equal to the determination reference hydrogen production amount S. _a It may not be more. In this case, since the ENABLE signal is not transmitted to the operation control means 2, the robot 1 becomes inoperable.
[0098]
Therefore, in order to prevent such inoperability, the following processing may be performed. That is, when the sequence manager 24 gives the increase instruction, the preparation time T is the same as in the first and second embodiments. _s Is calculated. The preparation time T after the increase instruction is given _s Has passed, the hydrogen generation amount by the reformer 9 is the determination reference hydrogen generation amount S. _a It is assumed that this is the case.
[0099]
Therefore, the sequence manager 24 performs the preparation time T after giving the increase instruction to the reformer 9 and the variable valve 10. _s Has passed, the hydrogen generation amount of the reformer 9 estimated by the fuel generation amount grasping means 30 is the determination reference hydrogen generation amount S. _a Even if not reached, the ENABLE signal is transmitted to the operation control means 2. Thereby, it is possible to prevent the above-described inoperability of the robot 1 from occurring.
[0100]
Moreover, in the said 1st-3rd embodiment, although the electrical double layer capacitor was used as an electrical storage means of this invention, using secondary batteries, such as capacitors other than an electrical double layer, and a lithium-ion battery. Also good.
[0101]
In the first to third embodiments, the electric power for operation is supplied from the electric double layer capacitor 4 to the robot 1. However, the power consumption of the robot 1 is small, and the electric power supplied from the fuel cell 5 is used. When the robot 1 can be operated, the electric power for operation may be directly supplied from the fuel cell 5 to the robot 1 without providing the electric double layer capacitor 4 and the constant current charging circuit 3.
[0102]
In the first to third embodiments, a reformer using methanol as a raw material is used. However, other types of reformers may be used.
[Brief description of the drawings]
FIG. 1 is a control block diagram according to a first embodiment.
FIG. 2 is an operation explanatory diagram of a fuel cell.
FIG. 3 is a configuration diagram of target pressure setting means.
FIG. 4 is a transition explanatory diagram of reserve tank pressure.
FIG. 5 is an explanatory diagram of changes in reserve tank pressure.
FIG. 6 is an operation flowchart of the sequence manager.
FIG. 7 is a time chart of power generation management means.
FIG. 8 is a time chart of power generation management means.
FIG. 9 is a control block diagram according to the second embodiment.
FIG. 10 is a configuration diagram of an observer.
FIG. 11 is a control block diagram according to the third embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Biped walking robot, 2 ... Operation control means, 3 ... Constant current charging circuit, 4 ... Electric double layer capacitor, 5 ... Fuel cell, 6 ... Hydrogen supply means, 7 ... Power generation management means, 8 ... Raw material tank, 9 ... reformer, 10 ... variable valve, 11 ... regulator, 12 ... reserve tank, 23 ... required hydrogen production amount calculation means, 24 ... sequence manager, 25 ... reformer production amount instruction means, 26 ... target pressure setting means, 29 ... Hydrogen consumption conversion means, 40 ... Observer

Claims (9)

In a legged mobile robot with an action plan function that operates according to a predetermined action plan,
A fuel cell for supplying electric power for operating the legged mobile robot; an operation control means for controlling the operation of the legged mobile robot according to the action plan; and the state of the fuel cell and the content of the action plan. A legged mobile robot comprising power generation management means for adjusting a power generation amount of the fuel cell according to the action plan. A raw material holding means for holding a raw material for generating fuel for the fuel cell; and a reformer for generating fuel for the fuel cell from the raw material supplied from the raw material holding means and supplying the fuel cell to the fuel cell,
The power generation management means instructs the reformer to increase or decrease the amount of fuel generated according to the fuel consumption of the fuel cell, and the content of the action plan is executed before the action plan is executed. In the action plan, when it is recognized that a large load operation that requires a power supply from the fuel cell of a predetermined level or more is executed in the action plan, before the large load operation is executed, The legged mobile robot according to claim 1, wherein a preceding process for instructing the reformer to increase the amount of fuel generation is performed. A reserve tank that supplies the fuel cell while holding the fuel output from the reformer;
The legged mobile robot according to claim 2, wherein the power generation management means performs the preceding process so that the pressure in the reserve tank does not exceed a predetermined upper limit pressure. The power generation management means, as the preceding process, generates a fuel generation amount for the reformer so that a fuel supply amount from the reformer to the fuel cell is not less than a necessary supply amount corresponding to the large load operation. The preparation time, which is an estimated time from when the fuel is actually generated at the target production amount set in accordance with the required supply amount from the instruction to increase the fuel supply, to at least the reaction delay characteristic of the reformer 4. The legged movement according to claim 2, wherein when the preparation time elapses after the instruction to increase, the operation control means is instructed to start execution of the heavy load operation. robot. A fuel generation amount grasping means for grasping the fuel generation amount by the reformer is provided,
The power generation management means instructs to increase the reformer according to at least the fuel generation amount grasped by the fuel production amount grasping means so that fuel is supplied at the required supply amount in the preceding process. The legged mobile robot according to claim 2 or 3, wherein a degree of the movement is determined. A fuel generation amount grasping means for grasping the fuel generation amount by the reformer is provided,
The power generation management means, as the preceding process, generates a fuel generation amount for the reformer so that a fuel supply amount from the reformer to the fuel cell is not less than a necessary supply amount corresponding to the large load operation. When the fuel generation amount grasped by the fuel production amount grasping means becomes equal to or larger than the target production amount set according to the required fuel supply amount after the increase instruction, the operation control means The legged mobile robot according to claim 2 or 3, wherein the start of execution of the heavy load operation is instructed. The power generation management means applies the fuel to the reformer so that the amount of fuel supplied from the reformer to the fuel cell is equal to or greater than the required supply amount according to the heavy load drive when performing the preceding process. A preparation time, which is an estimated time from when a fuel generation amount increase instruction is issued until fuel is actually generated at the target generation amount, is calculated. 7. The start of execution of the heavy load operation is instructed to the operation control means when the amount of fuel generated exceeds the target generation amount or when the preparation time has elapsed. The described legged mobile robot. The fuel generation amount grasping means grasps the fuel generation amount by the reformer using the power generation amount of the fuel cell, the temperature in the reformer, and the supply pressure of the fuel from the reformer. The legged mobile robot according to any one of claims 5 to 7, characterized in that: The legged mobile robot according to any one of claims 1 to 8, further comprising a power storage unit that is charged by output power of the fuel cell, and obtains operating power from the power storage unit.

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